Rice RURS 2015 Abstracts

8/19/2019 Rice RURS 2015 Abstracts

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Welcome!

On behal o this year’s Steering Committee and the Center or Civic Leadership, I am pleased to present the ab-stract booklet or the 2015 Rice Undergraduate Research Symposium (RURS). Now in its ourteenth year, RURSis the premiere event or undergraduates across all disciplines to present their research projects and compete orrecognition rom academic schools and research centers at Rice. Tis event would not be possible without theefforts o aculty, postdoctoral ellows, and graduate students rom Rice and the Houston community who havegraciously volunteered their time to evaluate the student presentations.

We are pleased that the Deans o the academic schools are generously sponsoring prizes to recognize exceptionalmerit and achievement in disciplinary research and presentation. Additionally, we are excited to offer a broadrange o special awards or outstanding projects related to the mission o the ollowing Rice research centers:

• Baker Institute for Public Policy • e Baylor College of Medicine EMS Collaborative Research Group• Center for Civic Leadership• Center for Energy and Environmental Research in the Human Sciences• Chao Center for Asian Studies

• e Howard Hughes Medical Institute• Humanities Research Center• e Ken Kennedy Institute for Information Technology• Rice 360°: Institute for Global Health Technologies• Rice Neuroscience• Rice Space Institute• Shell Center for Sustainability • Smalley Institute for Nanotechnology

We wish to thank the following individuals for their support of the event: Associate Provost Matt Taylor, DeanJohn Hutchinson, Dean Peter Rossky, Dean Lyn Ragsdale, Dean Nick Shumway, Dean Ned omas, Dr. David

Alexander, Dr. Farés el-Dahdah, Dr. Sonia Ryang, Dr. Dominic Boyer, Dr. Mark Escott, Dr. Rafael Salaberry,Dr. Allen Matusow, Dr. Richard Johnson, Dr. David Dickman, Dr. Gerald Rubin, Dr. Naomi Halas, Dr. RebeccaRichards-Kortum, Dr. Jan Odegard, and Dr. Caroline Quenemoen. As RURS is a student-organized event in con- junction with the Center for Civic Leadership, we would like to thank Dr. Elizabeth Vann, Mr. Michael Domer-acki, and Ms. Magdalina Rucinski for their guidance and support.

With best regards,Samantha ChapaChair, RURS 2015 Steering Committee

Steering Committee Members: Tony Li-Geng and Anveet Janwadkar


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Letter from the FounderRURS was founded in 2002 by Jenessa Shapiro, then a senior psychology major at Rice University. Dr. Shapiro isnow an Associate Professor in the Department of Psychology at the University of California – Los Angeles. Her re-search focuses on intergroup interaction and social stigma. Below is a message from Dr. Shapiro.

As an undergraduate I was always so impressed by my peers’ research projects. It was so impressive and excitingto hear about the cutting edge, important projects to which they were contributing. I couldn’t believe that Ricedidn’t have a orum or students to present their work to each other—an opportunity or our riends and proes-sors to see what everyone was working on. And so RURS was born. Tere was some skepticism—would Rice stu-dents want to present their work? I remember looking at the submissions on the evening o the deadline, worriedthat we would have a poor turnout. However, like most academic opportunities, students were waiting until thelast minute. I couldn’t believe my eyes. With one hour lef to submit, the submission numbers kept climbing. Weended up with way more submissions than we expected! Rice students were absolutely excited to present theirwork! Te first RURS was such a ulfilling experience. We filled the room with students presenting projects thatranged rom music to engineering.

I am so impressed with how RURS has grown! We went from the Grand Hall in the Student Center to the TudorField House. We went from a handful of awards to over 30 cash prizes. What has stayed the same, though, is thequality o the projects being presented. Flipping through the abstracts is incredible. Nothing has changed—Ricestudents are doing amazing things. And we all know this trend will continue each year that RURS takes place.

I am so grateul to Rice, the deans, and the other unders or supporting Rice undergraduate research and orkeeping RURS alive and thriving. I am also so flattered to learn that students will select the winner o the ShapiroAward. To know that Rice students will be the driving force behind this award is such a great honor. Have a greatconerence this year!

Sincerely,Dr. Jenessa Shapiro


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Table of Contents

Natural Science 5

Engineering

Solo 28

Group 34

Social Sciences 36Humanities 41

ScheduleHumanities Judging, Trauber Suite 4 p.m.

Poster Judging, Autry Court 4 p.m.

Dinner 6 p.m.

Awards 7 p.m.


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1: Treating Epithelial Cancers with Combination Therapies of

RapamycinMoez Dawood

Targeted therapies are designed to inhibit specic pathways driv -ing the malignant phenotype while concurrently decreasing sideeffects on normal cells. However, very requently, inhibition o thetargeted pathway activates compensatory mechanisms designedto bring the pathway back into equilibrium allowing or cancercell survival, a mechanism known as adaptive drug resistance. Tepurpose o this project is to identiy and abrogate the adaptivedrug resistance o epithelial cancers to rapamycin, an allostericinhibitor of mTOR (mammalian target of rapamycin), and torapamycin analogs in the PI3K (phosphoinositide-3-kinase)

pathway, the most commonly dysregulated pathway in epithelialcancers. Using 3D-cultures, rapamycin-induced morphologychanges and cell death were recorded. Changes in protein levelsdue to rapamycin-induced adaptive signaling were detected usingreverse phase protein arrays (RPPA), veried by Western blot-ting, and analyzed to determine potential adaptive mechanisms.Based on screening results from RPPA, rapamycin was combinedwith rationally selected drugs designed to thwart adaptive drugresistance to rapamycin. Tis co-extinction reinorced rapamycininto an effective inducer o cell death, ultimately bypassing drugresistance mechanisms and precluding the emergence o uturetherapeutic resistance. Successul combinations will be orwardedinto animal studies to demonstrate in vivo efficacy or the treat-ment o epithelial cancers.

2: The Role of A-myb during Embryonic Chick Corneal Develop-

mentCatherine Wu

A-myb, a member o the myb gene amily, is a transcription actorthat regulates cell differentiation and prolieration in specifictissues during development. While its role in prolieration hasbeen studied in human testes and breast tissue, little is knownabout its role during eye development. In the cornea o the chickembryo, A-myb has a transient expression pattern from E6 to E12.I hypothesize that A-myb plays a role in cell prolieration in the

cornea during embryonic chick development. To investigate this,techniques like in situ hybridization and immunohistochemistrywere used to compare cell prolieration in normal chick embry-onic corneas with that o A-myb knockdown chick embryoniccorneas. Results show that A-myb knockdown corneas have thin-ner corneas and decreased cell prolieration compared to normalcorneas.

3: Effect of Light on Gold Nanoparticle Heat Emission in Arabi-

dopsis Joann Pan

Gold has a variety of biomedical uses, in part due to its inertness

and relatively low toxicity. erefore, gold nanoparticles (GNPs)can be used in organismal application (Alkilany et al., 2013). Wehave identied a novel method to identify GNPs in situ in plants.Laser light is applied to Arabidopsis lea suraces, and as a resulto the ormation o vapor bubbles through absorption o heatenergy, acoustic signals can be detected at the sites where whereGNP localize. Using this system, we have found that Arabidopsiscan take up GNPs through the roots and transport particles up tothe leaves. To determine whether the GNP-dependent heat gener-ation caused by light exposure can trigger cellular heat responsesin the plants, we generated a heat-responsive transgene produc-ing an easily detectable reporter, the beta-glucuronidase enzyme(GUS). e reporter gene was composed of the regulatory regionof the Hsp17.4 gene fused to the GUS transgene. e transgene

was introduced into plants using a flower dipping technique, and25 transgenic Arabidopsis were selected by growth on hygromycinB containing media. As a control, the Hsp17.4:GUS transgenicswere exposed to high temperature (37oC) for 4 hours; blue color-ation was detectable throughout the leaves. When the transgenicplants were exposed to GNP and treated with laser light, GUSstaining was apparent around the lea vascular tissue, consistentwith the localization of GNPs. erefore, our work demonstratesthe easibility o using nanobubble detection to monitor local-ization of GNPs in plant tissue, provides evidence of uptake andtranslocation of GNPs in plants, and demonstrates GNP-depen-dent heat generation in Arabidopsis leaves.

4: First Review of Functional Role: White-fronted Capuchins(Cebus albifrons equatorialis) as Seed Dispersers at La Hesperia

Biological Station, EcuadorRebecca Maher

A significant proportion o neotropical woody plants produceruits that are dispersed by animals. With the expansion osecondary orests and increasing deaunation, the unctionalrole o seed dispersers within an ecosystem must be consideredin conservation strategies. At La Hesperia Biological Station inPichincha, Ecuador, a small troop of the critically endangeredWhite-ronted capuchins (Cebus albirons equatorialis) hasestablished pathways traveled daily through secondary orest and

agricultural fields. A study o their home range use and dietaryhabits was conducted to evaluate their effectiveness as dispersersor native and agricultural ruiting trees within the range. FromNovember to early December, the troop was observed or ruithandling and movement trends. Dispersal syndromes o reported-ly preerred ruits were reviewed through direct collection in theeld and literature research. Tree assemblages were determined

within the reserve in secondary and primary orests. O the list opreerred ruit trees, at least 8 genera are ound within the occu-pied home range o 55 ha with an exponential shannon diversityo 5.9. White-ronted capuchins were ound to be most effectiveat dispersing the seeds o trees with small ruit that grow well in

Natural Science


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orest gaps. Te presence o agricultural ruiting trees promotesthe use o predictable movements that may limit the successuldispersal o native species. Conservation priorities should protectprimates o all sizes.

5: Investigating host-microbe interactions in DrosophilaMeera Namireddy

Several host-deense mechanisms are conserved rom Drosophilato humans, making them ideal organisms or studies o innate

immunity. Previous studies have indicated that innate immunecells can be primed to react more vigorously afer initial inection.In Drosophila, the cellular innate immune response is carriedout by plasmatocyte phagocytosis o microbes. We are interestedin testing how plasmatocytes react to priming. We primed theies by injecting them with dierent doses of heat-killed E. coli.We then injected live E. coli and performed colony-forming-unitassay to assess the bacteria clearance efficiency. We have oundthat the priming response is dose-dependent and displays a bell-shape dependence, in which a moderate priming dose producesthe highest efficiency. However, the priming response declines at ahigher priming dose. Since phagocytosed bacteria are destined orlysosomal degradation, we hypothesize that lysosome processes

are required or modulating the priming response.

6: Establishing the stiffness of different layers of the develop-

ing embryonic corneaRebecca Federman

Tere is an increased demand or keratoprosthesis due to a lack ocorneal donors. It is necessary to know the tissue’s biomechanicalproperties in order to engineer a biomimetic corneal prosthetic.We propose to measure the stiffness o the layers in a developingembryonic cornea to determine the biomechanical properties inthis matrix during organogenesis. Since localized protein expres-sion contributes to the properties o the corneal tissue, correlating

the stiffness o different corneal layers to expression o matrixproteins could give insight on how proteins can influence theseproperties during organogenesis. We are going to use three cor-neas each from the E6, E7, E8, E10, E12, E14, E16, and E18 phaseso development. We will will immunostain or perlecan to labelthe corneal basement membranes. Using Atomic Force Micros-copy, we will determine the relative stiffness o each layer o thedeveloping corneas and will localize dynamic stiffness in the tis-sue to varying protein expression o perlecan. We predict that thatthe posterior Descemet’s membrane is the stiffest ollowed by theendothelium and the anterior basement membrane. Te stromawill be the sofest tissue layer during early stages o development,but will increase in stiness aer corneal condensation at E16.

7: Effects of TiO2 Nanoparticles on the Lysosomal-Authophagy

SystemVinh Tran

Autophagy is a complex pathway that mediates degradation ocytoplasmic materials in mammalian cells. Evidence suggeststhat TiO2 nanoparticles (NPs) aect the autophagy pathway, butthe mechanism and outcome are unknown. We hypothesize thatTiO2 NPs activate autophagy at the transcriptional level but alsoimpair lysosomal stability thereby blocking autophagic clearance.I am testing this hypothesis by monitoring lysosomal stability incells treated with TiO2 NPs. Particularly, I am using HeLa cells

genetically modied to overexpress the transcription factor EB, amaster regulator o lysosomal biogenesis and unction. Cells wereincubated with TiO2 NPs of 15, 50, or 100nm diameter. Cellularuptake of the NPs was determined by ow cytometry and therelationship between cellular uptake and NP concentration in themedia was established. Lysosomal stability was analyzed usingdye quenched-bovine serum albumin, a compound designedto display fluorescence upon cleavage by lysosomal hydrolases.Preliminary data suggest that the eect of TiO2 NPs on lysosomal

unction is size and concentration dependent. Results rom thisstudy will lead to a detailed understanding of the eects of TiO2NPs on lysosome activity and the autophagy pathway.

8: Phylogenetic signal of optimal mating number in Bruchid

seed beetlesMarisol Palomares

Sexual conflict is conflict that arises between the sexes due todiffering optimal fitness strategies regarding sexual reproduction.Sexual conict occurs in seed beetles (Family Bruchidae) in whichmales harm emales during mating. However, also during copu-lation, male ejaculate has the benefit o providing nutrients to theemale, since as adults these beetles do not eed. Tereore mul-

tiple matings might be beneficial to the emale, despite physicalharm. Tis study examines effects o mating requency on emalefitness or several species o closely related seed beetles. Individuaemales were mated rom 0 up to 7 times and their total liespan(in days) and ecundity (total number o eggs laid over their lies-pan) were measured to determine an optimal mating number oreach trait. Variation among species was compared using phyloge-netic inormation to answer the question o whether the degree osexual conflict (as measured by optimal mating number) is moresimilar or more closely related species than or more distantlyrelated species, suggesting that traits related to sexual conflict areevolutionarily conserved.

9: MAPK/ERK signaling in the nervous system of a Drosophila

model of MLIVKelly Tomasevich

In mucolipidosis type IV (MLIV), lysosomes are unable to fusewith the late endosome because of Transient Receptor Poten-tial-Mucolipin (TRPML) dysfunction. TRPMLs are non-speciccation channels that unction predominantly in endosomal lyso-somes. TRPMLs are responsible for the release of Ca2+ ions from

the late endosome and lysosome into the cytosol, which serves asa signal to SNARE proteins to fuse the two vesicles. MLIV is char-acterized by severe cognitive deficits and motor deficits, whichprimarily occur during development and deteriorate slightly

throughout a patient’s lie. Te purpose o this project will be todetermine whether MAPK signaling is diminished in Drosophilamodel of MLIV. Ras signaling proteins are required in groups of

7-8 (nanodomains) to acilitate the uptake via endocytosis andreturn of phosphatidylserine (PS) to the plasma membrane via thelysosome. Because of TRPML dysfunction, PS becomes trappedin the late endosome, which is unable to use with the lysosomeand return to the plasma membrane. By analyzing the expressionof ERK and phosphorylated-ERK (P-ERK) in both wild type andMLIV mutant Drosophila, and conrming a lower expression ofP-ERK in the mutant genotype, we can conrm that the ERK/MAPK pathway is inherently linked with MLIV.


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10: Tracheal Analysis of lov MutationsRadhika Mohan, Rami Dibbs

e Beckingham lab is using the Drosophila model to determinethe function of the jim lovell gene on fruit y development. Basedon previous work using the Gal4-UAS system, our lab unexpect-edly ound that lov is expressed in the tracheae afer knockingthe gene out with Gal4 lines like breathless. Recently, several newmutations in lov have been discovered within the fly communi-ty, which can help us understand the role o lov urther. For our

studies, we have focused on the GS15 and NP42 transposon inser-tion mutations. In studying larvae homozygous for GS15 or NP42,we initially ound that the mutants exhibited sluggish behavior,impaired locomotion, and high death rates soon afer hatching.We then set out to determine whether these phenotypes correlat-ed with tracheal deects. We examined the dorsal trunks, trans-

verse connectives, and the filzkorper on the spiracles. Within allcategories, both GS15 and NP42 mutations produced similar andpronounced morphological deects. Tese results provide moreconcrete proo that lov is involved in tracheal development. Wenow wish to see whether these tracheal abnormalities correlatewith sluggish locomotion. e GS15 and NP42 mutations weretoo lethal to permit these studies so we are working to address

this question with dierent lov mutations : - lov47, lov PZ01, andlov PZ10.

11: Environmental DNA (eDNA) detection of the endangered

Houston toad Bufo houstonensisPreeya Bhavsar

Species detection can be critical to the long-term survival ospecies. However, species detection is ofen difficult in manyenvironments at different lie stages, and in general, or popula-tions at low density. Environmental DNA (eDNA) is a sensitiveand efficient, non-invasive sampling method that relies on DNAobtained rom water samples to detect species. We aimed to apply

the eDNA approach to detect the endangered Houston toad Bufohoustonensis. Houston toad distributions are currently describedbased on auditory surveys and field captures that are difficult,time consuming, and costly. To test the ecacy of the eDNA ap-proach or the Houston toad, we are using Houston toad specificprimers and universal amphibian primers to test 1) simulated fieldeDNA water samples that have been spiked with Houston toadeggs and egg connective tissue and 2) eDNA water samples takenrom controlled aquaria housing Houston toads. Concurrently,we are developing species-specific primers or the Houston toadthat can be used as probes against other closely related amphibianspecies that are ound in the Houston toad habitat. Te results othis study will extend the current detection capabilities or known

Houston toad populations and assist in discovering novel popula-tions o Houston toads.

12: Identification and characterization of PEST motifs in the

adeno-associated virus stereotype 2 viral proteins and assem-

bly-activating proteinByunguk Kang

PEST motifs are specic amino acid sequences known to becommon protein degradation tags involved in the ubiquitin deg-radation pathway. PEST motifs are rare among most proteins, asthey are ound in only 10% o all mammalian proteins. However,a majority of proteins with rapid turnover rates contain PEST

motifs. To date, there have been no documented reports of inves-tigating potential PEST motifs within our viral vector of choice,adeno-associated virus (AAV). A quick algorithm search revealedthat AAV stereotype 2 (AAV2)’s cap gene (encoding capsid viralproteins) contains at least two potential PEST motifs (VP PEST1and 2). e assembly-activating protein (AAP), located in analternative ORF o the cap gene and essential or virus capsid as-sembly, also contains three potential PEST motifs (AAP2 PEST1-3). Our preliminary data suggest that ablating VP PEST1 led to a

significant decrease in transduction output compared to wild typeAAV2. Silverstaining of these mutants shows that there was noapparent deect in capsid assembly. In order to identiy and char-acterize PEST protein’s function in VP and AAP, we will construct

various mutants with multiple mutations within VP PEST1 and2, as well as AAP2 PEST1-3. Silverstain or Western blot will beconducted to assess any capsid assembly deects. We will conducttransduction assays, internalization assays, and heparin-bindingassays to characterize and investigate the PEST motifs’ role in theinfectious pathway of AAV2.

13: NK Cells in the Pathogenesis of Multiple SclerosisLindsy Pang

Multiple sclerosis (MS) is a neuro-inammatory disease. MS isalso considered an autoimmune disease because it is caused byone’s own immune system attacking and deteriorating the myelinsheath. Te purpose o the sheath is to accelerate the speed oneural conduction signals. Damage to the myelin sheath thatleads to a loss of neural function is a characteristic feature of MS.Oligodendrocytes (OL) are the only glial cells o the central ner-

vous system that produce myelin sheaths surrounding the axons.Natural killer (NK) cells are lymphocytes of the innate immunesystem that could be associated with MS. NK cell recruitment inthe brain and its bias against secreting IFN-ϒ have been previous-ly associated with multiple sclerosis progression and remission,respectively. Our research so ar has shown that activated but notresting NK cell can perform demyelinating activity against humanOLs but from HLA mismatched donors. Using MO3 cells that areHLA negative, we then ound that demyelinating activity o acti-

vated NK cells does not depend on HLA haplotype. Our currentresearch will test as to whether activated NK cells, not resting,result in greater demyelinating activity regardless o the presenceor absence o HLA mismatch.

14: Dynamics of Gamma Oscillations in Absence EpilepsyKatherine Yu

Childhood absence epilepsy is one o the most common types opediatric epilepsy. Some anti-epileptic drugs (AEDs) are known

to paradoxically increase seizure activity, but the mechanism isnot known. Stargazer and tottering mice are mutant models oabsence epilepsy secondary to unique genetic mutations. Teeect of AEDs on various frequency bands was analyzed withinthe electroencephalogram (EEG) for patterns that would predicteither seizure exacerbation or freedom. Mice were recorded atbaseline and aer intraperitoneal injection of AEDs. Preliminarydata show a significant increase in the baseline absolute poweracross the 13-60 Hz frequency band in stargazer mice comparedto both tottering and WT mice (p


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sociated with seizure exacerbation only in stargazer mice, causesa reduction in relative gamma power in stargazer mice, but an in-crease in relative gamma power in WT and tottering mice. Finally,

flupirtine, which enhances potassium channel activity, exacerbatesseizures and reduces relative gamma power in both mutants.Tereore, changes in relative gamma power activity during theinterictal state may serve as biomarkers for AED ecacy.

15: Novel non-invasive skin sampling agent shows efficacy in

isolating DNARoger Liang

Tere is an urgent need or novel, economical technologies toprevent skin cancer. ese cancers are diagnosed 3.5 milliontimes and claim 20,000 lives per year in the U.S alone. Cutaneoussquamous cell carcinoma (cuSCC) is diagnosed 700,000 timesand kills up to 8,000 per year in the USA. As o now, skin cancerprevention screening is based on clinical examination ollowed bybiopsies o already-existing preneoplastic lesions. Te molecularexamination o at-risk but clinically normal tissue is not currentlyperormed to assessed or chemoprevention. Our project includesusing the novel, non-invasive epidermal sampling agent, “DXB,”to sample and isolate DNA to identiy key drivers o progression

rom normal tissue to preneoplastic lesion to invasive cancer.Our goal is two-fold; we want to (1) optimize DXB in nucleic acidyield and reliability, and (2) use DXB to create a panel of biomark -ers rom a controlled in vivo experiment. Here, we demonstrateprogress in optimizing DXB to produce strong DNA yields.

16: Variation in performance by Belonocnema treatae gall

wasps across live oak genotypesLeah Topper

We examined performance dierences in a population of B. treat-ae gall wasps on our closely related but geographically distinctpopulations of live oak (Q. fusiformis from central Texas, Q.

virginiana from Louisiana, Q. virginiana from central Florida, andQ. geminata from central Florida). We placed three saplings from

each population under a heavily-inested, mature live oak in cen-tral Texas for two weeks in Spring 2014 during optimal B. treataeadult emergence and oviposition. Ten, we housed the saplingsin a mesh tent to exclude gall wasps, predators, and parasitoids.Afer galls had ully developed, we recorded: (1.) average numberof galls per leaf, (2.) average gall diameter per tree, and (3.) per-centage o galls per tree population reaching two size thresholdsrelated to survival - the tree threshold (2.62 mm) and the naturalenemy threshold (5.82 mm). We ound there were more galls perleaf on the Q. virginiana and Q. fusiformis populations than onQ. geminata. In addition, the few galls on Q. geminata that grew

never reached the tree or natural enemy thresholds which willgive them ~0% chance of emergence. Within Q. virginiana pop-ulations, there was significant variation in perormance, but thisdid not vary with geographic distance.

17: What is the effect of flower shape on bumblebee foraging

behavior in the presence of predators?Lauren Howe-Kerr

Te flower preerences o pollinators are influenced by floral char-acteristics as well as by prior encounters with ambush predators.Importantly, we might expect an interaction between flower shapeand predation risk, since predators within closed flowers may be

more difficult to detect and escape. In this study, I tested whetherflower shape influences the oraging behavior o the commoneastern bumblebee (Bombus impatiens) in the presence of replicas

o crab spiders, known ambush predators o bumblebees. Openand closed artificial flowers were distributed equally in a oragingarena, and bees were allowed to orage in the arena first withoutspiders and then with crab spider replicas present on hal theflowers o each type. I examined whether there was a change inthe bees’ preerences or open and closed flowers in the presence

and absence o crab spider replicas, whether the bees avoidedflowers with crab spider replicas, and whether oraging preerencechanged throughout the duration o the trials. I encounters withpredators affect the flower shape preerence o oraging bees, florareproductive success could also be influenced. Te interactionbetween flower shape and predation risk could thereore be oneo the selective pressures acting on flower diversification andevolution.

18: Usage and Implications of the Term “Social Niche”Benjamin Johnson, Rachel Marren

Since its rst usage in academic literature in 1993, the term “socianiche” has been used with increasing frequency, oen in the

context of “social niche construction.” We reviewed primary andsecondary literature that included the term “social niche” andound that the term is usually lef undefined and perceived defini-tions differ greatly between papers in their scope and application.Upon review o compiled inormation and traditional definitionso the ecological niche, we proposed a definition o a social nicheas, “any social environment in which an individual has non-zerotness.” We claried the relationships between social niches andrelated terms such as social roles and social behaviors. Tis workwill allow or more direction in uture research.

19: The Role of SpeB Secreted Protease Activity in GAS Infec-

tions Anjali RaghuramGroup A Streptococcus (GAS) is a human-specic pathogenthat causes inections ranging in severity rom uncomplicatedpharyngitis (strep throat) to lie-threatening necrotizing asci-itis (esh-eating disease). Secreted protease B (SpeB) is a keyGAS virulence factor for tissue destruction, dissemination, andmortality in animal inection models and humans. Despite itsunambiguous role in virulence, the recent discovery o severalmutations in genes implicated in SpeB expression, secretion andpost-translational processing has led to the idea that GAS may beunder selection to decrease SpeB secreted protease activity duringinfection. To test this hypothesis, we measured SpeB secreted

protease activity and sequenced the genome of 3615 GAS strainstaken rom comprehensive population-based collections in Fin-land, Georgia (US), Iceland, Minnesota (US), Norway, Ontario(Canada), Sweden and the former East Germany. e resultsdemonstrated that greater than 80% of GAS strains are SpeB pos-itive. Te genome data indicate that mutations in transcriptionalregulators are the most common cause of decreased SpeB secretedprotease activity. Taken together, these data conrm that mostGAS strains have a wild type SpeB phenotype and reinforce theimportant role of SpeB in human infections.


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20: Implications of Sea-level Rise for Whooping Cranes on the

Texas Gulf CoastMolly Cisneros

Much of conservation biology centers on the preservation ofspecies and populations. However, with climate change alteringthe world, new threats to species are arising, including severedrought and sea-level rise. e whooping crane, Grus americana,has been protected for decades under the Endangered Species Actand the conservation actions taken have brought the flock that

over-winters in Aransas National Wildlife Refuge in Texas fromless than 20, to over 300 individuals. While the ock is growing,their winter range lays along the Texas Gulf Coast, an area at riskfor land loss due to sea-level rise. To evaluate the severity of thisthreat, we modeled five different inundation scenarios represent-ing a variety of likelihoods for occurrence. By using GIS mappingwe were able to demonstrate that the crane habitat in the Reugewill remain relatively un-disturbed until sea-levels rise by over1m. However, depending on the behavior o the barrier island andthe rivers providing sediment, land may be lost due to erosion bysea currents or reduced sediment deposition. Tus, while sea-levelrise is not an immediate threat to the survival o the flock, thereare enough unknowns that it warrants urther, more in-depth

investigation.

21: Lipid biomarker of neural stem and progenitor cells affects

Nr2e1 (Tlx) transcriptional activitySricharan Gopakumar

Adult hippocampal neurogenesis is a process in the brain bywhich new neurons arise rom a pool o neural stem cells. Tishighly regulated process takes place in the hippocampus, a regionassociated with learning and memory, and declines with age,suggesting a possible mechanism or age-related cognitive decline.Previously, our lab utilized 1H-NMR to observe an enrichmentof molecules in neural progenitor cells (NPCs) resonating at 1.28

ppm, a lipid-based spectral signal characterized as a high concen-tration of monounsaturated fatty acids (MUFAs). Tlx, an orphannuclear receptor highly expressed in NPCs, has been shown tobe a major regulator o adult neurogenesis. We hypothesize thatmonounsaturated atty acids are unctionally important signalingmolecules regulating the NPC cell cycle through control of Nr2e1transcriptional activity. Here, we demonstrate the changes intranscriptional activity of Nr2e1 post-MUFA exposure through amammalian one-hybrid lucierase assay and altered gene expres-sion of Tlx downstream targets via qPCR. Ultimately, the interac-tion of Tlx and endogenous lipid molecules appears to be involvedin determining NPC fate. is mechanism to better manipulateneural progenitor cell behavior may allow us to better control and

maintain adult neurogenesis throughout lie.

22: Evaluation of gnaq in the Development of a Zebrafish Port

Wine Stain ModelDavid Lakomy, Meron Teklu

Port Wine Stain (PWS) is a congenital defect that results in hy -pertrophic and dilated vasculature. Currently, PWS has no cure oranimal model. Our project aims to recreate the PWS phenotypewithin zebrafish and elucidate the underlying molecular mecha-nisms o the disorder. A single nonsynonymous somatic activatingmutation in the gene encoding or a guanine nucleotide bind-ing protein, GNAQ, has been identied in many PWSs. We are

creating a Cre/lox inducible line of transgenic zebrash expressingwild-type gnaq, the R183Q PWS mutation, and a Q209L mutationfound in uveal melanomas. We will activate GNAQ within clones

o the vascular endothelium whereby we can observe their effectson vessel patterning and dynamics with spatiotemporal control.Injection o in vitro transcribed RNA o the gnaq variants indi-cates that early mutant gnaq expression results in a rupture o theblastoderm attributable to epithelial monolayer integrity deects.We have used this early phenotype to determine potential down-

stream eectors of GNAQ. Potentiation of the blastoderm lysisphenotype with co-injection o yap1 and gnaq indicate possibleHippo pathway activation through gnaq. With urther develop-ments in achieving the vascular phenotype, this model can helpelucidate PWS etiology and serve as a platform to test potentialdrug therapies.

23: Organization of the vestibular signals to the navigation

circuit in the mouse brainDayae Jeong

Te vestibular system is a sensory system that is essential orbalance and spatial orientation. Its sensory receptors, located inthe organs o the inner ear, relay inormation to the brainstem

vestibular nuclei and cerebellum through the afferent fibers o the vestibulocochlear nerve. Signals rom the vestibular nuclei thenproject to many regions o the brain, but no anatomical map o

vestibular responding areas yet exists in rodents. We aimed tomap out the vestibular responding regions and pathways in themouse brain by electrically detecting the expression o a neuralactivation marker (c-Fos: an immediate early release gene). Inorder to activate the vestibular system, we electrically stimulatedthe vestibular receptors bilaterally for 30 minutes, then perfusedthe animal with 4% paraormaldehyde. Te mouse brain was thensectioned and histochemically processed or the c-os antibody.We observed neural activation in a number o brain regions

known to be involved in navigation, including the vestibular nu-clei, the cerebellum, the hippocampus, and the entorhinal cortex.Tree dimensional contour maps and quantification o cell countsor each o these regions are currently being perormed.

24: Effects of MUC 16 Reduction on Chemotherapeutic Drug

EfficacyYasmin Khalfe

Large, heavily-glycosylated proteins called mucins are ound onepithelial cell suraces and perorm important unctions, includ-ing protecting rom pathogens, hydrating the cell suraces, andregulating signaling and transcription. Mucin 16, or MUC16, isutilized as a serum marker o cancer because its irregular expres-

sion plays a role in metastasis. When cancer is present, mucins areoverexpressed and cover the entire cell surace, which can make itdicult for chemotherapeutic drugs to reach the cell. By reduc-ing mucin expression, this barrier can be overcome which couldallow drugs to be delivered to cells more efficiently. Te projecttests whether reducing MUC16 enhances chemotherapeutic drugeectiveness. MUC16 SiRNA-mediated knockdown was em-ployed on the ovarian cancer cell line, SKOV3-IP, using scramblesiRNA as a control. With qRT-PCR, levels of MUC16 mRNA weremeasured to show the effectiveness o the knockdown over 24, 48and 72 hours. Results showed that the MUC16 siRNA-mediatedknockdown eectively lowered levels of MUC16. Chemother-


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apeutic drugs, paclitaxel and carboplatin, were administered tothe cells. Using the LIVE/DEAD assay, the eectiveness of thedrugs was determined. Reducing MUC16 resulted in a signicant

amount o dead cells as compared to the control, thereore che-motherapeutic drug efficacy was enhanced.

25: Zebrafish Immune Responses: Infection of Zebrafish

Through External Exposure to CandidaChinenye Nnoromele

Innate immunity deends a host against inectious agents. Currenttechniques used to investigate innate immune unction maynot reflect the usual route o environmental challenge. Insteadthey overcome the inefficiencies o environmental challenge byinjecting pathogens to bypass epithelial barriers or by co-cultur-ing pathogens and immune cells. Unortunately these methodsail to recapitulate the complex interactions between hosts andpathogens. Knowing this, the aims of this study were to deter-mine i zebrafish could succumb to inection only rom externalexposure and determine i this mode o injection is more efficientthan current injection practices. In this study, zebrafish embryoswere exposed to GFP-labeled Candida under dierent conditionsto determine i inection through this mechanism was possible,

efficient, and reproducible. Our data suggests that 2dp zebra-ish embryos can be inected by Candida rom external exposurein a method at a higher efficacy compared to current injectionmethods in terms o number o embryos inected and time. Inuture work, the aims include maximizing the reproducibility andefficacy o this mode o inection and to utilize this technique tobetter understand the immunological responses within the zebra-ish experimental model.

26: The Effect of Drought on Differential Tree Species Mortality

in East TexasCarolina Osuna

Climate change is set to have multiple effects on our globalclimate, one o which is an increase in the requency and inten-sity o droughts. Droughts are a major orest health stressor thatcan cause long-term tree mortality and provide potential uelfor wildres. e record-breaking drought of 2011 in Texas wasunprecedented in its intensity. Timber lost to drought and wildrein 2011 resulted in a $3.4 billion economic impact on Texas. etolerance of dierent tree species was identied using 2012-2013Forest Inventory & Analysis (FIA) tree species and status data or42 counties in east Texas (the more humid and hardest hit region)along with other relevant datasets (drought, soil moisture, eleva-tion, etc.) provided by the U.S. Department o Agriculture. Tesedatasets were assembled and converted into spatial data in ArcGIS

in order to identiy highly drought tolerant or intolerant species,along with significant characteristics that affected their survival.With this information, east Texas forest managers can make more

inormed decisions in light o climate change in order to mitigatethe consequences of future drought on Texas forest health.

27: Loss of NMNAT2 Impairs Development of the Cerebral CortexDaniel Connolly

Nicotinamide mononucleotide adenylyl transferases (NMNATs)are best known as enzymes that synthesize nicotinamide adeninedinucleotide (NAD+). In mammalian brains, NMNAT2 is themajor NMNAT isoform expressed. Deleting NMNAT2 function

in mice causes significant axonal deterioration and neuronalloss. Recent studies have found that NMNAT2 also plays roles inneurodevelopment. It has been shown that Nmnat2 deletion leadsto defective axonal outgrowth. However, the role of NMNAT2 inembryonic brain development is less explored. Using NMNAT2knockout mice, we sought to elucidate the roles of NMNAT2 inneurogenesis, neuronal survival, and neuronal migration duringthe development o the cortex rom a single-layered sheet ocells to a six-layered cortex. We ound that similar numbers o

neurons were born but ewer neurons survived rom embryonicday 14.5 (E14.5) to E18.5. At E14.5, the numbers of proliferatingcells within the brain were the same between Nmnat2 KO brainsand controls. However, at E18.5, there were reduced numberso intermediate progenitor cells and postmitotic neurons. Tesendings provide evidence that NMNAT2 is important to ensureproper migration o cortical neurons in the development o thecerebral cortex and is also important or neuronal survival even atembryonic stages.

28: Genetic Control of Paternally-Derived X-chromosome Inacti-

vation in Marsupials Using CRISPR/Cas9Shireen Usman

Random X-chromosome inactivation occurs in eutherian emale(XX) mammals to control the dosage o X-linked genes. Tenon-coding RNA, Xist, is known to mediate inactivation ineutherian mammals, but it is not ound in metatherians (marsu-pials). Instead Rsx (RNA-on-the-silent X), a seemingly analogousnon-coding RNA, is thought to selectively inactivate the paternal-ly inherited X-chromosome in emale marsupials. Rsx activity hasbeen correlated to X-chromosome inactivation, which is thoughtto occur as a result o the transcription o repeat-rich RNA thatcoats the inactive paternally-inherited X-chromosome. However,the unction o Rsx has not yet been confirmed by examiningthe reactivation o the paternal X-chromosome through muta-

tion. Our goal is to utilize CRISPR-Cas9 knockout technology toeliminate Rsx expression and consequently X-chromosome inacti vation in the emale opossum. Specifically, this study attempts toinduce CRISPR/Cas9 mutations of Rsx in female Monodelphisdomestica fibroblasts to confirm the essential role o this gene inthe process o metatherian X-inactivation. Trough an analysiso mutant opossum cells, we provide insight on the molecularprocesses involved in sex chromosome regulation in marsupialsand provide a baseline or urther exploration o the evolutionarydivergence between metatherians and eutherians.

29: The Co-Inheritance of Sickle Cell Anemia and Alpha-Thalas-

semia and Its Effect on Cerebrovascular DiseaseSean LiuSickle Cell Disease (SCD) is an autosomal recessive blood dis-order in which hemoglobin, the major protein o red blood cells(RBCs), is mutated. Deoxygenated sickle hemoglobin undergoesintracellular polymerization and distorts the RBC into a dis-tinctive sickle shape. Patients with sickle RBCs suer hemolyticanemia, recurrent acute vaso-occlusive events, inflammation, andchronic organ damage. Cerebrovascular disease is one o the mostserious clinical complications o SCD and without clinical inter-

vention can lead to early childhood mortality. Tere is evidencethat the co-inheritance o alpha-thalassemia, a deletion o one orboth o the alpha globin genes, protects patients with SCD against


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the development o cerebrovascular disease. In order to addressthis hypothesis, I used polymerase chain reaction to genotype thealpha-thalassemia status o SCD patients to determine i there is acorrelation between the incidence o cerebrovascular disease andthe co-inheritance o alpha-thalassemia. It is expected that the re-quency o any alpha globin deletion will be lower in SCD patientswith a history o cerebrovascular disease, while patients moreresistant to cerebrovascular disease will have a higher requencyo alpha-thalassemia. Te results should show an evolutionarily

significant difference in the rate o cerebrovascular disease-reesurvival in patients with SCD and alpha-thalassemia.

30: Inter-bioherm Grainstone Flow and Accumulation in an

Upper Cambrian Microbial Reef Complex of the Wilberns Forma-

tion (James River, Mason County, Texas)Meron Fessahaie

Research ocusing on microbialites in academia, as in industry,has gained interest due to large discoveries o hydrocarbon inpre-salt microbial reservoirs oshore Brazil. Surveys and researchprograms have been initiated in the Upper Cambrian outcrops inMason County within the Wilberns Formation through a Rice/Trinity Industry consortium to better understand the overallheterogeneity, complexity, and interconnectivity o pre-salt res-ervoirs. Upper Cambrian microbial mound and ree complexeswithin the Wilberns Formation crop out on cliff exposures alongMill Creek and the Llano/James Rivers, providing a 3-D detailed

view o these microbial ree complexes. Along the James River,two well-preserved 5-6 m high relief bioherms are separated bya series o bioclastic grainstone layers intercalated by thin bedso detrital fine silt and sand, which resemble surprisingly wellthe environmental growth conditions of 2-3 meter tall modernHolocene living subtidal microbial thrombolytic rees surroundedin the Adderly Tidal Channel on the edge of Great Bahama Bankmargin between Exuma Cays. e similarities between the Ho-

locene subtidal microbial bioherms and the ones we study in theUpper Cambrian Wilberns Formation will provide meaningulcomparisons or understanding the interactions between microbi-al hermal growth and their inter-ree sediments.

31: Does Seed Dispersal Loss Influence Treefall Gap Closure?Kevin Czachura

Treefall gaps present unique opportunities for competitiveseedling growth by providing microclimatic differences romsurrounding orest. An important source o seeds in these gapscomes rom seed rain by birds. Te unctional extirpation o birdspecies on Guam has led to a loss of seed dispersal. Rota andSaipan support populations o bird species and thus serve as com-

parative models o normal seed dispersal. We hypothesized thatrates o closure o treeall gaps would be aster on Rota and Saipancompared to Guam because fewer seeds would be dispersed intogaps on Guam. To test this hypothesis, we created 44 small treefallgaps across the three islands. We took hemispherical photographso each gap immediately beore and afer gap creation, thenmonthly over the next 13 months. We used gap analysis sowareto calculate canopy openness then assessed gap closure rates bycomparing canopy openness over time relative to baseline pre-gapcanopy openness. Te results o this project will demonstrate theeects that bird loss has on Guam’s treefall gap closure rate. isinormation could provide universal insight on the impacts o

seed dispersal loss on orest structure and could guide conserva-tion efforts in dispersal-deficient ecosystems around the world.

32: Do the Hinge-helices in Lactose Repressor (LacI) Inde-

pendently Recognize Operator DNA Sequence?Madeleine Hewitt, Joseph Xu

Te tetrameric lactose repressor, LacI, is a classic example o aregulatory DNA-binding protein. Each LacI monomer is com-posed o N-terminal helix-turn-helix DNA-binding domain (res-

idues 1-50), a hinge-helix linker region (residues 51-59), and aninducer-binding core domain (residues 60-360). Mutations in res-idues 51-60 result in loss of binding to operator DNA without im-pacting nonspecific DNA binding, suggesting that the hinge-helixis required or specific binding. In addition, crystallographicstructures show that the hinge helices bend the DNA sequenceto allow specific binding by helix-turn-helix domains. However,direct demonstration that the hinge-helices can promote specificbinding independently has not been established. Our researchexplores several methods or investigating independent operatorsequence binding by the hinge-helices. First, LacI truncations canbe generated that contain deletions in each o the binding regions

via trypsin digestion or in vitro transcription and translation.Binding anity of the truncated proteins can subsequently beassessed by DNA pull-down and/or lter binding assays. Demon-strating that hinge-helices alone exhibit specificity in recognitioncould potentially benefit design o DNA binding proteins.

33: A zebrafish model for Wnt/β-catenin signaling during

blood-brain barrier developmentWesley Chou

e blood-brain barrier (BBB) is crucial for maintaining ho-meostasis and preventing disease in the nervous system. Wnt/β-catenin signaling has been shown to be required or properBBB development and maintenance, although the precise roles

o Î²-catenin remain poorly understood since it promotes bothgene transcription and cell-cell adhesion. Using a novel transgeniczebrash line that expresses tissue-specic uorescent β-catenin,this project will determine at what time points and in what celltypes Wnt/β-catenin signaling is required for BBB formation.Overexpression of uorescent β-catenin mRNA in zebrash em-bryos produced mutant phenotypes, suggesting that the fluores-cent orm is unctionally identical to the wild-type orm and canthus be used for a transgenic line. To separate the dierent roles ofβ-catenin, we created another transgenic line that expresses an in-ducible form of β-catenin fused to an Engrailed repressor. Whenactivated, the dominant-negative β-catenin will repress transcrip-tion o Wnt target genes in endothelial cells without disrupting

cell-cell adhesion. Overall, this study will allow or real-timemonitoring of essential tissue-specic Wnt/β-catenin signalingduring BBB development.

34: Sexes Respond Differently to Water Supply Rates in a Peren-

nial GrassRachel Hodge

Poa aracnifera is a dioecious grass native to the Great Plainsthat shows a geographic gradient in population sex ratio. In themoister sections of its range, populations of P. aracnifera aredominated by emales, suggesting these outperorm males at highsoil moisture. We conducted a greenhouse study to determine i)


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whether P. aracnifera’s sexes respond dierently to soil moistureand ii) whether the response o the sexes to soil moisture has agenotypic component. We subjected three P. aracnifera genotypes

to five water supply rates over nine months. We used lea countas a proxy o individual fitness. Analyses indicate an interactionbetween water level, sex and origin. In particular, emales romthe moister section o the range are advantaged at a high waterlevel compared to males rom the same region. Tis did not occurin the other two genotypes or which water supply did not change

the hierarchy o perormance between the sexes. In conclusion,results suggest that geographical differences in sex ratios can bepartially explained by unique adaptations o the sexes. In particu-lar in one o our genotypes emales outperorm males at high soilmoisture.

35: Using Volatile Chemical Production to Report on DNA Deliv-

ery to Undomesticated Microbes in Complex SettingsTim Wang

Quantied analysis of microbial DNA delivery provides invalu-able insight into the mechanisms o bacterial evolution. Troughour novel Methyl Halide Transferase (MHT) gas reporter system,we can analyze interactions between undomesticated microbes

beyond controlled lab environments and in their natural com-plex environments (ie. soil, waste water, biomass, ood). TeMHT gene encodes for enzymes that release methyl halide gas,which can be monitored to correlate with DNA delivery withoutdisrupting the experimental environment. We will demonstratethe viability of the MHT system by using it to quantify bacterialconjugation eciency. e MHT reporter gene and a hyperactiveconjugative transposon from an undomesticated Enterococci

strain will be genetically inserted into the genome o a modelBacillus subtilis 168 (BS168). e modied bacillus will serve asthe donor o the transposon DNA to a recipient bacillus strain.Monitoring gas levels during this process will give indication of

the sensitivity of the MHT reporter system. us, we hope toexhibit the MHT gas reporter system as a systematic and quan-tifiable method to study microbial DNA delivery in complexenvironments.

36: Effect of Predation Risk and Flower Shape on Bumblebee

PollinationClare Randolph

Pollinators play a large role in the reproduction of most owering

plants. I pollination is affected, flowers may be unable to repro-duce. In this study, we aimed to determine whether predation riskand flower shape affect which flowers common eastern bumble-bees (Bombus impatiens) choose to visit and pollinate. Predation

and flower shape are related because the presence o predatorsis dangerous to bumblebees, and flower shape may play a role inhow a bumblebee treats the perceived risk. We allowed bees toorage in an arena with artificial flowers (male and emale, openedand closed), and did trials with and without crab spider repli-cas. We tracked pollination using powdered ood dye as a pollenreplica. Te quantity o dye deposited on emale flowers was thenmeasured using a spectrophotometer. By measuring the amounto dye stuck to emale flowers, we determined their fitness and thefitness o the male flowers when they were closed or open, andwhen they had or did not have spider replicas. I spider replicas orflower shape change the pollination behavior o bees, there could

be selection pressures that are causing flowers to evolve in thewild. Tese pressures would be stronger in the wild.

37: The CRISPR Cas-9 Genome Editing System in Pancreatic

Adenocarcinoma Hypoxia ResponsePeter Cabeceiras

e Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR) CRISPR Associated Sequences (Cas) system is a pro-karyotic acquired immunity against viral and plasmid invasion.

e CRISPR Cas9 system is highly conserved throughout Bacteriaand Archaea. Recently, CRISPR/Cas has been utilized to editendogenous genomes in eukaryotic species. In certain contexts, ithas proven invaluable or in vitro and in vivo modeling. CurrentlyCRISPR genome editing boasts unparalleled eciency, specicity,and cost compared to other genome editing tools like Transcrip-tion Activator-Like Eector Nucleases (TALENs) and Zinc FingerNucleases (ZFNs). is project discusses the background theoryof CRISPR, and reports novel approaches to genome editing withthe CRISPR system in pancreatic cancer to study the hypoxiaresponse and tumor radioprotection.

38: In Vivo Production of Malonic AcidRichard Tong

Malonic acid is a dicarboxylic acid used as an intermediate inthe production o pharmaceuticals, vitamins, and barbiturates.Te ormation o malonic acid rom oxaloacetic acid (OAA) byreaction by with hydrogen peroxide has been shown by highperformance liquid chromatography (HPLC) and uorescenceassays. Te project seeks to find an in-vivo method o producingmalonic acid in Escherichia coli cells via a OAA+H2O2 reaction.Production of H2O2 is achieved through knock-out of catalaseand over-expression o NADH oxidase and ormate dehydroge-nase (FDH); OAA could be produced by a malate dehydrogenase(MDH) or phosphoenolpyruvate carboxylase (PEPC) catalyzed

reaction; e OAA+H2O2 reaction is catalyzed by a peroxidase.Several genes will be knocked out or over-expressed in cellsaccordingly, and production is tested by taking the cell lysate orwhole cells and assaying malonic acid production.

39: Modeling HCN Conductance Distribution and its Functional

Role in a Collision-Sensitive NeuronEric Sung

Synaptic integration plays a significant role in neuronal compu-tations. Tis process is mediated by the morphological structureo the neuron and also dendritic voltage-gated ion channels. Forinstance, locusts possess an identified visual interneuron knownas the Lobula Giant Movement Detector (LGMD) which receives

and processes incoming visual inputs to mediate collision avoid-ance escape behavior. e LGMD possesses a class of voltage-gat-ed ion channels known as HCN channels. Little is known abouthow these channels contribute to the LGMD’s function. In orderto better understand the role o these HCN channels on synapticintegration in the LGMD, we develop a computational model thatresembles the structure of the LGMD and its extensive branchingpatterns. First we uncover the HCN channel distribution. We setup an optimization problem, fitting our model to experimentaldata. Using dual dendritic recording data, we are able to deter-mine the appropriate distribution o HCN conductance usingMATLAB’s optimization toolbox. en, we model incoming


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synaptic inputs and record the model’s responses. We show thatan HCN conductance can explain the responses of the LGMD todifferent types o visual stimuli observed experimentally beoreand afer pharmacological blockade.

40: Uncovering the Kinetics of rRNA-Binding Using Novel Mu-

tant Ribosomal S8 Proteins Jaime Martinez

Te bacterial ribosomal protein S8 is an essential component o

the 30S subunit and has a conserved, well-characterized structure.S8 also serves as a translational regulator o the spc operon mRNAtranscript in Gram-negative bacteria, which encodes severalother ribosomal proteins. Te conormational disorder seen inGram-negative S8, unlike its well-ordered Gram-positive coun-terpart, is thought to be key in its double unctionality, suggestingdifferent RNA-binding mechanisms between these two classes oS8. In order to determine the kinetic details o S8-RNA complexformation, mutant S8 proteins from Gram-negative Escherichiacoli and Gram-positive Bacillus anthracis were engineered witha non-interering tryptophan residue directly on the RNA-bind-ing interace, whose fluorescence is quenched substantially uponRNA-binding. Using stopped-flow rapid mixing experiments to

study both complex association and dissociation will yield thekinetic parameters o RNA-binding, shedding light on the mecha-nism o S8-RNA complex ormation as it relates to the conorma-tional disorder o the protein.

41: Measurements of Component Azimuth of USArray Trans-

portable ArrayBeineng Zhang

e Transportable Array is a network of 400 three-componentbroadband seismographs placed in temporary sites across theUnited States in a regular grid pattern with station spacing oabout 70 km and a residence time o two years. It is designed

to provide a oundation or integrated studies o continentallithosphere and deep Earth structure over a wide range of scales.

For modern seismic studies, the rotation o vertical and horizon-tal components is critical in the separation o different types oseismic waves. However, aligning a seismometer is a difficult taskespecially when it requires site-specific declination corrections.We analyzed the teleseismic compressional waves (P-waves)recorded by the network in order to evaluate the north-compo-nent azimuths o the stations. For each station, we adopted anSNR-weighted-multi-event method to calculate the azimuths thatbest t the P-wave motions of all the events. Our data include atotal o 758 stations o which 707 stations that are eligible or theanalysis recorded more than 10 earthquakes bigger than or equal

to magnitude 5. Te results showed that in general, the stationsare almost perectly installed with azimuths smaller or equal to 2degrees while variations are present within certain stations.

42: Predicting Pandemic: A Multidimensional Analysis of

Emerging Infectious Diseases and their Potential for Global

Transmission Jackie Olive

Inectious diseases comprise the largest cause o adolescent deathworldwide, and a leading cause of death in adults. Since the Ebola

virus disease outbreak in West Arica, it has become an urgent

global health need to assess the state o emerging inectiousdisease epidemics. Tis study first analyzes the progression o andinternational public health response to the Ebola epidemic. FromWHO epidemic data reports, Middle East Respiratory SyndromeCoronavirus (MERS-CoV) and Avian Inuenza A (H7N9) wereidentified as two significant regional epidemics to ocus researchand resources. Chagas Disease and Chikungunya were identifiedas emerging local threats to Harris County, TX. Key epidemicgrowth actors studied include human mobility and migration,

poverty, vaccine deficits, conflict regions, and in particular, con-centrated vector distribution and animal reservoirs. Moreover,it is critical to develop universal global health policies to ensureimmediate regulation o these outbreaks.

43: The Effects of Predation Risk on Bumblebee Foraging

Behavior Angela Martini

In order to survive, prey species ofen alter their behavior inresponse to predation threat. Here, we investigate the effects thatthe threat o crab spiders has on the oraging behavior o commoneastern bumblebees (Bombus impatiens). Bumblebees evaluateflower quality and preer visiting high reward flowers. However,

crab spiders also evaluate flowers and preer waiting on high qual-ity owers to ambush bees. To examine changes in bee behaviorin response to predation threat, we initially allowed bees to orageindividually in an arena containing equal numbers o high-re-ward, yellow owers (40% w/w sucrose solution) and low-reward,white owers (20% w/w sucrose solution). In the second trial,we introduced camouflaged spider models on two high-rewardflowers that were used to simulate attacks on bees. In the thirdtrial, we removed the spider models. From trial video-recordingswe determined flower choice, distances traveled between flowers,and inspection times. Further analysis will reveal whether thesebehaviors changed in response to predator attacks and whether

they remained altered afer spiders were removed. Tese resultswill show how prey alter their behavior when given a tradeoffbetween oraging efficiently and saely and will provide insight onhow pollinators’ predators may affect flower trait selection.

44: Optimization of Globin Stability in MyoglobinsWilliam Ou

Optimization of the stability of the myoglobin (Mb) fold is anattractive goal or the design o recombinant hemoglobin-basedoxygen carriers. One region of interest is the EF loop, which con-nects the E and F helices that sandwich the heme-binding pocket.To study this region, variations in Mb sequences at positions cor-responding to residues 79-86 in sperm whale Mb were compared

across a variety of animal species. Based on the analyses done,codon degeneracies at each position in the EF loop were designedto include only the amino acids that occurred at high requencyin aquatic species or residues that occurred in aquatic species butnot land species. Te mutations were introduced into the spermwhale Mb gene, which was previously cloned into the E. coliexpression vector pVP80K. Preliminary screening of transformedE. coli colonies for red color and sequencing of the isolated DNAindicated that we successfully generated a Mb library with thedesired reduced amino acid alphabets. Future work will involvelarger scale screening o the library as well as use o this semi-ra-tional library design technique to target dierent regions of Mb,


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again ocusing on sampling various amino acid combinationspresent in nature.

45: Do-It-Yourself Assembly of a new Rat GenomeSarah Nyquist

As the cost o DNA sequencing continues to plummet, theproduction o complete, end-to-end genome sequences orindividuals is becoming increasingly easible. However, despitereductions in sequencing cost, the process o generating end-to-

end sequences or all o an individual’s chromosomes remainstechnically challenging. In the past, such genomes have typicallybeen produced by consortia involving hundreds or thousands oscientists working in tandem. Here, we describe a procedure orend-to-end sequencing o a mammalian genome that (i) can beperformed by a single person; (ii) has the potential to be per-formed, from start to nish, in under a week; and (iii) costs lessthan $15K. is procedure entails (a) production of a DNA-Seqexperimental library, which contains random subsequences othe genome of interest; (b) a Hi-C experimental library, whichdescribes the three-dimensional folding of the genome; and (c)

an array o powerul algorithms which transorm these datatypesinto a finished sequence. Although the procedure has not been

perormed in its entirety, I have perormed steps (a) and (b) orthe genome o an individual o the genus rattus (rat), and expectto present a new rat assembly. Tis represents the first time, to ourknowledge, that a mammalian genome has been sequenced andassembled, end-to-end, by a single person.

46: Role of Akt in Tumor AngiogenesisRishi Suresh

Angiogenesis—the ormation o new blood vessels rom preex-isting blood vessels’, allows tumor cells to obtain nutrients orgrowth and metastasis. Previous research done in Dr. Phung’s labhas investigated the role o Akt, an important growth signaling

molecule, in tumor angiogenesis. Te literature has shown thatAkt increases tumor angiogenesis. Te Akt gene amily has threeisoforms, Akt1, Akt2, and Akt3. Our lab has shown that Akt1promotes angiogenesis, whereas Akt3 suppresses it. e aim ofthis project is to further study the role of Akt3 in the tumor angio-genesis. Specically, we have learned that loss of Akt3 increaseslevels o HIF-1±. Tus, this experiment is trying to determinewhether specic deletion of HIF-1± will rescue the Akt3-/- phe-notype and consequently decrease associated tumor growth andangiogenesis. Gene-silencing technology with short hairpin RNA(shRNA) will be used to perorm a double knockdown o bothAkt3 along with HIF-1±. e results of this study will help deter-mine whether modulating Akt3 levels is an eective anti-cancer

treatment option.

47: Survey of Native and Invasive Ant Biodiversity in Big Thicket

National PreserveGabriela Zambrano

Big icket National Preserve in East Texas, one of the mostbiologically diverse areas in the United States, consists o a con-uence of biomes normally found in the Eastern, Central, andSouthern regions o the United States. Tis overlap gives rise to anextremely high diversity o both plant and animal species. Despitethe biodiversity o the region, however, relatively little is under-stood about the distribution o native ant species in the preserve.

In addition, the recent incursion o the invasive tawny crazyant,ϒNylanderia ulva, threatens to dramatically alter the existingdistribution and abundance o native ant species in the region.In order to catalog the biodiversity and distribution o both thenative ant species of Big icket National Preserve and invasivespecies such as N. ulva, samples were collected rom every unitin the preserve, with a ocus on sites that are near waterways inboth major units and corridor units, and away rom waterwaysin major units, during May 2014. Our work now provides the

groundwork or a comprehensive estimate o the ant species pres-ent in Big icket National Preserve that can be used in futureant species surveys and a record o N. ulva incursion that willprovide a baseline or urther research.

48: The role of p53 in Xenopus embryonic kidney developmentNicholas Cho

p53 is a well-studied tumor suppressor protein that preventstumorigenesis by regulating the cell cycle and apoptosis odamaged cells. Tis protein has been shown to regulate multiplesignaling pathways that are responsible or normal developmentand differentiation, including the Wnt pathway. Upregulationo Wnt signaling in embryonic Arican clawed rog, Xenopus

laevis, kidney results in reduced nephric differentiation. A similarphenotype has also been observed upon the inhibition of p53 inXenopus as well. Based on this previous work, we hypothesizethat p53 plays a role in normal kidney development by interact-ing with components of the Wnt signaling pathway. To test thishypothesis, stabilized antisense oligonucleotides (morpholinos)were used to knock down p53 expression. Immunouorescencewas used to observe the phenotype upon the knockdown withinthe embryonic kidney. While we have demonstrated that p53protein is expressed in embryos at stages in which the kidney isdeveloping, we were not able to detect the knockdown of p53through Western blot. Although we are still trying to veriy ourknockdown of p53 by Western blot, we observed that immunou-orescence markers or differentiated kidney were highly reducedas compared with controls, suggesting reduced differentiation onephron structures.

49: The Correlation Between Chronic Hyperkalemia and T Wave

Heights in ElectrocardiogramsMohammad Alsheikh-Kassim, Ryan Pappal

Hyperkalemia, or abnormally high potassium levels, is a com-mon condition in end stage renal disease patients that classicallymanifests in a heightened T wave peak on the patient’s electrocar-diogram. However, in recent studies, this ECG diagnostic techniqueshowed poor sensitivity, with as low as 32% of patients in hyperkale

mia displaying peaked T waves. is retrospective study is examin-ing end stage renal patients at the Ben Taub General Hospital Emer-gency Center who were eligible for emergent dialysis and receiveda basic metabolic panel to assess potassium levels and a 12-leadelectrocardiogram from 2010-2012. Each patient visit was analyzedfor potassium levels and for R wave, S wave, and T wave heights aswell as T wave durations in leads V2, V3, and V4. A linear correla-tion test was run between T wave heights and potassium levels. Aninitial analysis of 8 patients totaling to 31 data points showed nosignicant correlation between T wave height and potassium level,r(31) = 0.24, R2 = 0.056. According to our statistical analysis, Twave height did not accurately predict serum potassium levels.


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50: Seryl tRNA Synthetase is Implicated in Zebrafish AngiogenesisLawrence Zhu

tRNA synthetases are a class o enzymes that link specific tR-NAs to cognate amino acids. Tey are important housekeepingenzymes, without which cellular viability is impossible. Recently,several tRNA synthetases were implicated in non-canonical activi-ties such as apoptosis, transcriptional regulation, and splicing.e hi3817 D. rerio mutant identied through a viral mutagenesisscreen contains an insertion in the seryl tRNA synthetase (SerRS)

gene resulting in the loss o sars mRNA. Tis line was crossedinto a Flk1-GFP background line to visualize vasculogenesis. emutant phenotype maniested as ectopic branching rom interseg-mental vessels (ISV) in homozygous mutants, and was able to berescued with microinjection o wild type sars mRNA. Further-more, sars mRNA with deective aminoacylation activity was alsoable to rescue the mutant phenotype, suggesting that the knownunction o tRNA synthetase is not necessary or angiogenicactivity. Further rescue experiments using different ragmentso the sars mRNA have identified a region o the gene necessaryfor normal ISV development. Current eorts to understand theunctionality o the protein are ocused on showing the presenceo specific angiogenic cleavage products o SerRS using westerns,

and using tagged sars constructs to ollow potential cleavageevents responsible or regulation o angiogenic activity.

51: A forward genetic screen to study salt-induced peroxisome

proliferationSammira Rouhani

Peroxisomes are small, membrane-enclosed organelles that con-tain enzymes involved in essential energy-generating metabolicreactions, like β-oxidation. Peroxisomes are derived from theendoplasmic reticulum, and mature peroxisomes can divide toorm more peroxisomes. However, detailed mechanisms o per-oxisome biogenesis or prolieration are not understood. In plants,

peroxisome abundance increases with salt treatment; additionally,peroxisome functions, like β-oxidation, may be involved in NaClinhibition of root growth (Kao, unpublished). We conducted aforward-genetic screen (SB screen) to nd the proteins involvedin peroxisome biogenesis or prolieration in Arabidopsis. In-dole-3-butyric acid (IBA) is beta-oxidized into indole-3-aceticacid (IAA) in peroxisomes, and IAA inhibits root growth. NaClincreases IBA potency, possibly due to increased peroxisomeabundance. We selected putative SB mutants with elongated rootson media containing both IBA and NaCl. We are retesting phys-iological phenotypes and conducting immunoblotting to explorecandidate lesions. We found that SB89 lacked thiolase protein,so it is probably a ped1 mutant. We also ound a possible matrix

protein import defect in SB31, and for this mutant, we will usewhole-genome sequencing to identiy causal mutations. Furtheranalysis of the SB mutants will elucidate the interplay of peroxi-some unctions and abiotic stress.

52: Studying cell-cell interactions between human salivary

acinar-like cells (hSACs) and human myoepithelial cells (hMECs)Corina Badillo

Many head and neck cancer patients suer from xerostomia, ordry mouth, as a result o radiation therapy. Unortunately, currenttreatment or xerostomia is only palliative and consists o admin-istering sialagogues or saliva substitutes. To improve the quality

o lie o these patients, our lab ocuses on generating an artificialsalivary gland in vitro rom healthy cells isolated prior to thera-py or re-implantation into the patient afer radiation therapy torestore saliva production. My studies focus on further characteriz-ing human salivary acinar-like cells (hSACs) , human myoepithe-lial cells (hMECs), and the cell-cell interactions between the twocell types via bright-field imaging and immunofluorescence toinform the tissue engineering of a salivary gland project. hMECswere isolated rom human salivary gland tissue and were assessed

or myoepithelial biomarker expression (α-smooth muscle actinand cytokeratin 14) through immunofluorescence. Further workwill consist o studying the cell-cell interactions between hSACsand hMECs to inform the salivary regeneration project.

53: Characterization of Sickle Cell Disease HemoglobinsKristin Sweeney

e naturally occurring β Glu6 →(HbS) mutation in adult humanHb causes Sickle Cell Disease (SCD). Irreversibly damaged sicklecells occlude capillary beds and prematurely lyse, causing inflam-mation o blood vessels due to damage rom toxic acellular com-ponents including oxidized hemoglobin and free heme (Bunn,1986). Damaged vascular systems result in decreased oxygen

transport, vaso-occlusion, and strokes (Belcher, 2014). e long-range goal of this project is to characterize the eects of β Glu6→(HbS) and Lys (HbC) mutations on the stability and oxidativeproperties o three types o recombinant hemoglobins. HbS andHbC are being expressed in three vectors: pHb0.0, in which theN-terminal valine is replaced with an initiator methionine in bothhemoglobin subunits; pHE2, in which methionine is added priorto the initiator valine and cleaved by excess methionine amino-peptidase; and pHb0.1, in which the two α subunits are genetical-ly cross-linked by a glycine linker. Te rates o oxygen binding,HbS polymerization, HbC crystallization, autooxidation, hemeloss, and apoglobin unolding will be measured or all six recom-binant Hbs. Te HbS and HbC variants are expected to be lessstable, and characterization o their properties will help developnew therapies to treat patients with these genetic disorders.

54: Does RTC3 mediate sulfite-induced inhibition of ribosome

biogenesis in Candida albicans?Neha Pal

Candida albicans is a species o yeast that lives naturally insidehumans. Under most conditions, C. albicans is not harmul to itshuman host. In immune-compromised individuals, however, C.albicans can infect its human host; this infection has a mortalityrate o orty percent. C. albicans is a particularly serious threat be-cause o its resistance to sulfite, a chemical released by neutrophils

as a line o deense against pathogens. Understanding the way C.albicans interacts with sulfite could have important medical impli-cations. is project focuses on orf19.1862, referred to as RTC3,and its interactions with sulte and rapamycin, which is a Torc1kinase inhibitor. RTC3 is predicted to mediate the sulte-inducedinhibition o ribosome biogenesis. A series o experiments werecarried out to measure the gene expression of RTC3 in sul-fite-treated and rapamycin-treated cells. Te sensitivity to sulfiteand rapamycin of wild-type cells and RTC3 deletion mutants wasalso examined.


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55: Nanoscale Radiation Measurements in Proton Therapy

Beams for RadiobiologyTimothy Hallacy

Proton therapy has risen to the forefront of cancer radiotherapytreatment due to its ability to deliver a high radiation dose to atumor with less damage to surrounding healthy tissue as com-pared to photon beams. For the same radiation dose, the relativebiological eectiveness (RBE) of proton radiation is higher com-pared to photon radiation. To understand the molecular mecha-

nisms related to the higher proton RBE we developed a novel toolto co-localize single proton tracks traversing a single cell by usinguorescent nuclear track detectors (FNTDs). FNTDs are Al2O3:C,Mg crystals that undergo a radiochromic transformation uponexposure to ionizing radiation. Using conocal microscopy, thisradiochromic transformation was used to reconstruct 3D tracksof protons passing through the FNTD and trace them back to alayer of adherent cells growing on the FNTD substrate. Moreover,the fluorescence intensity o the tracks can be correlated to thelinear energy transfer (LET) of the protons, providing a metric formeasuring the LET of single proton tracks. is could potentiallyallow for investigations into the relationship between LET andRBE.

56: Characterization of lacI- araC Dual Feedback Oscillator

DerivativesBrian Ho

Oscillations in gene expression are a driving orce behind nat-urally occurring rhythms in organisms. Te characterization onovel oscillatory gene networks helps urther the understandingo the mechanisms o larger natural oscillatory networks. It hasbeen ound previously that the lacI- araC dual eedback oscillatorproduces robust oscillations across a wide range o parameter

values. Te network is composed o transcriptional activatoraraC activating itsel and transcriptional repressor lacI inhibiting

itsel and araC. We will create novel gene networks by editing theexisting network topology. Tis will be accomplished by removingthe sel-eedback loops and characterizing the new networks. Weuse PCR and restriction enzymes to mutate the hybrid promoter(Plac/ara-1) to specic operator sites. e O1 and Osym sites aredeleted to remove lacI self-feedback and the I1/I2 sites are deletedto remove araC self-feedback. Mutated plasmids will be trans-formed into E. coli and imaged using microuidic-aided time-lapse uorescence microscopy. To measure the uorescence, thelab has developed a robust cell tracking algorithm which can tracka lineage o cells and measure their individual fluorescence. Wewill also confirm the promoter knockouts were successul usinginduction assays.

57: How Does the Hinge Region of the Lactose Repressor Inter-

act with the lac Operator Sequence?Jaskeerat Gulati, Matthew CruzSince its discovery by Jacob and Monod in 1963, the lac oper-on has been studied extensively to better understand cellularresponse to external stimuli. Each dimer within the tetramer-ic lactose repressor protein (LacI) is able to bind lac operatorDNA, thereby affecting the level o transcription o the operon.O particular importance is the LacI hinge helix, comprised oamino acid residues 51-60, which links the inducer-binding coredomain and helix-turn-helix DNA-binding domain, and inserts

as a olded dimer into the minor groove o the DNA to elicit abend. Without the olded hinge helices, LacI binds nonspecificallyto DNA. No studies, however, have investigated the independentbinding o the hinge helix dimer with DNA. In order to explorethis relationship, we synthesized the hinge helix with a cysteineat position 52 to induce dimerization through the oxidation o adisulfide linkage. We will utilize nitrocellulose filtration assay andpulldown assay techniques to assess the degree o binding o thedimeric peptide to the DNA. Te results will reveal the specificity

with which the hinge helix independently interacts with DNA.Tis work has the potential to aid in effectively being able to targetspecific DNA sequences or binding and modification.

58: Characterization of OsAAE3, an Oxalyl-CoA Synthetase in

Oryza sativaPeter Lambert

Oxalate, the smallest o the dicarboxylic acids, is produced inmany plants through a variety o mechanisms. Tis acid has beenshown to play an important role in both plant physiology anddeense, specifically in regards to metal detoxification, nitrogenfixation, sucking and chewing insect deterrence, and calciumoxalate crystal production. Recently, the confirmation o a novel

pathway o oxalate metabolism in Arabidopsis through the useof an oxalyl-CoA synthetase AtAAE3) has sparked a search forhomologous pathways in other plants. Tis study identifies Oryzasativa ACYL-ACTIVATING ENZYME3 OsAAE3: Os04g0683700as a gene encoding an oxalyl-CoA synthetase. Tis activity isparticularly interesting given that rice also possesses the morecommon oxalate catabolic pathway utilizing oxalate oxidases. Toinvestigate the function of OsAAE3 we have produced a recom-binant enzyme that demonstrates activity against oxalate in vitro,exhibiting Michaelis-Menten kinetics with a Km of 98.24 ± 19.94µM and a Vmax of 6.880 ± 0.3218 µmol/min/mg. Additionally,we have introduced OsAAE3 into Ataae3 null mutants, and found

that plants expressing OsAAE3 in the mutant background havea lower oxalate content than the Ataae3 null mutants, which cor-relates with the reduction in calcium oxalate crystals seen in theOsAAE3 plants.

59: Sulfite and Gene Expression in Candida albicansDivya Naik

Candida albicans remains harmless to most humans, but cancause disease in immunocompromised people. Candida isresistant to host-produced chemicals that inhibit mitochondrialrespiration, such as nitric oxide and sulte. Metabolic pathwaysconvert sulfite to hydrogen sulfide, which inhibits cytochrome C.Sulfite regulates 5 unctional groups o genes, including the alter-

native oxidases which help Candida resistivity to nitric oxide. Tetwo genes o interest to this project are AOX2, which is an alterna-tive oxidase gene activated in response to electron transport chaininhibition, and SSU1, which is involved in sulfite removal. Tisexperiment works with the deletion o strains Δzc2, Δmet5, andWTH testing of the expression of genes AOX2, SSU1, and controlgene ACT1. Cells were grown and treated with sulte, RNA wasextracted, and then Reverse Transcriptase qPCR was performed.My hypothesis is that AOX2 expression is increased in response tosulte in the Δzcf2 and WTH strains, but not in Δmet5, since it ismissing the met5 enzyme o sulfite reductase, which is thought tocontrol the conversion rom sulfite to hydrogen sulfide. Learning


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about sulfite response is not only useul to the Candida communi-ty but also to the pharmaceutical industry in potentially devel-oping drugs to target Candida albicans in immunocompromisedpeople.

60: Genetic suppressors of the Arabidopsis pex6-1 mutantKendall Burks

Peroxisomes are eukaryotic organelles that sequester metabolical-ly essential oxidative reactions. In Arabidopsis thaliana, peroxi-

somal pex) mutants exhibit characteristic phenotypic deects thatprovide a ramework or understanding peroxisome biogenesisand function. e Arabidopsis pex6-1 mutant carries a mutationidentical to one ound in human patients with a heritable peroxi-some biogenesis disorder. Tis mutant is deficient in the import ooxidative enzymes that promote seedling growth prior to photo-synthetic competence. When grown without a fixed carbon sourcein the dark, pex6-1 seedlings display short hypocotyls, a pheno-type that can be corrected with exogenous sucrose. To elucidatethe molecular functions of PEX6, we are screening for suppressormutations that restore sucrose independence to pex6-1. To date,we have isolated 3 conrmed suppressor mutations that show

varying extents o suppression. Afer determining i any o these

mutations are allelic with the single pex6-1 suppressor previ-ously described, we plan to identiy the deective genes throughwhole-genome sequencing. By studying peroxisomal decienciesin plants with the same genetic deects as humans, we may betterunderstand not only the unctioning o peroxisomes in plants, butalso the etiology o these atal diseases.

61: Engineered, Affordable Glycans as New AntimicrobialsPooja Yesantharao

Tough gastroenteritis is a common cause o morbidity andmortality worldwide, especially in inants in the developing world,

vaccines against such enteric inections are largely ineffective.

Tis poses a need to produce an effective, economical therapy orthis disease. Human milk oligosaccharides such as 2-ucosyllac-tose could serve as suitable antimicrobials, because they mimicthe interactions between histoblood group antigens and viruses,and thereore prevent pathogen-host binding. Tis project aimsto prepare a carbohydrate analog or viral binding and inhibitioncontaining a 2-fucosyllactose-like linkage. Multiple experimentalpathways have been unsuccessully explored to synthesize 2-uco-syllactose through the use of a lacZ- lacY+ lacI- strain of MG1655E. coli with serial deletion of the purR, fucI, and wcaJ genes. Inthis study, we harvest and investigate the viral inhibitory capacityof the O-polysaccharide component of lipopolysaccharide (LPS)on O128:B12 E. coli, which contains a Fucα1,2Galβ linkage that

is similar to 2-ucosyllactose. We have engineered and optimizedO128:B12 to overexpress LPS, through altered growth conditionsor bacterial transformations with the ypdI, rcsB, or lpxC genes.Our results will point to a powerul method or large-scale syn-thesis o complex carbohydrates and a new therapeutic approachor gastroenteritis.

62: Effects of Mutation Accumulation on Relative Fitness of

Escherichia coliMarie-Therese Valovska

Strong evolutionary selection orces lead to predictable mutationsin a species’ genotype, and corresponding changes in phenotypic

characteristics. In the case o strong selection pressure, mutationsmust generate beneficial traits and increase the overall fitnesso the organism, or the species risks extinction. Adaptation toecologically complex environments, on the other hand, involvesweak selection orces, which yield less predictable mutations asan increase in fitness is not necessary or survival. Under suchconditions, even the accumulation o deleterious mutations isnot atal, and as a result, they are allowed to persist. In previousresearch, we used parallel evolution to identiy adaptive mutations

in twelve lines of E. coli 1 which were evolved independently innutrient-rich media. We determined that mutations in globalregulators ArcA and RpoS play a large role in metabolic selectionduring adaptation to complex environments (Saxer et al. 2014).Here, we designed mutation accumulation (MA) experiments tominimize the effects o selection across independently evolved,bottlenecked lines. We used genome sequencing and relativefitness assays to determine the genotypic and phenotypic effects omutation accumulation in order to better understand the role oweak selection orces.

63: Changes in Oligosaccharide Structure of MUC1 in Cervical

Mucus Serve as Markers of Implantation Window Judy YangTe timing o embryo transer in the endometrium is importantin in vitro fertilization. MUC 1 is a mucin glycoprotein found inhigh amounts in the cervical mucus with a protein core that isheavily substituted with O-linked oligosaccharides. In previousstudies, oligosaccharide stru

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Rice RURS 2015 Abstracts