Upload
chantale-fernandez
View
36
Download
0
Tags:
Embed Size (px)
DESCRIPTION
Identifying genes that confer resistance to ultraviolet radiation in the unicellular alga Chlamydomonas. Bryan LaBore Northern Arizona University Mentor: Dr. Karen VanWinkle-Swift. Why is this research important?. Prevent damage caused by UV (UV-C & UV-B) - PowerPoint PPT Presentation
Citation preview
Identifying genes that confer resistance to ultraviolet radiation
in the unicellular alga Chlamydomonas
Bryan LaBore
Northern Arizona University
Mentor: Dr. Karen VanWinkle-Swift
Why is this research important?
•Prevent damage caused by UV (UV-C & UV-B)
•Increasingly important with hole in ozone
•Damage to:•DNA mutations skin cancer•Protein defective enzymes altered metabolism•Lipids leaky membranes cell death
Harmful Effects of UV-B Radiation
• Avoidance (sunscreens)– Common mechanism in plants– Melanin in humans, and topical sunscreens
• Repair systems for DNA damage• Degrade and re-synthesize proteins and lipids
Protection from UV Radiation
Chlamydomonas as a model
• Unicellular green alga
• Photosynthetic• Requires sunlight
uvs-1 mutant
How we got the uvs-1 mutant
mutagen
WT uvs-1
0 sec
15 sec
30 sec
45 sec
Survival after exposure to UV radiation
0 25 50 750.001
0.01
0.1
1
10
100wildtype
uvs-1
UV dose (seconds)
Wild-type vs. uvs-1 Survival at Various Doses of UV Radiation
New sup mutation
How we got the sup mutant
Super sunscreen?Super repair?
mutagen
UVS supsvegetative cells
0 10 20 30 40 50 60 70 80 90 1000.0001
0.001
0.01
0.1
1
10
100u220
uvs
18-3
16-1
8-2
3-2
9-1
4-1
2-2
25-1
15-2UV dose
(continuous light protocol)
Suppressor mutants have regained resistance to UV radiation
UV Dose(sec)
Now What?• What does the suppressor mutation do? • We must isolate the sup mutation from the uvs mutation, which requires some basic genetics
A Review of Basic Genetics
Parentals Recombinants
Defective UV repair? (uvs)
Super sunscreen? (sup)
Genetic Analysis of the UV resistant suppressor mutants
Normal UV repair (not uvs)
Normal sunscreen (not sup)
Normal
NormalUV resistant (uvs sup)
UV resistant (uvs sup)
UV sensitive (uvs)
SUPER UV resistant?!?! (sup)
Further Research To Be Done
• Isolate the sup mutation in all of the sup mutants• Perform further survival curves on the isolated mutants•Determine the mechanism behind each sup mutation (Super sunscreen? Super repair?)
Thank you to:• NASA• NAU• Dr. Nadine Barlow• Kathleen Stigmon• Dr. Karen VanWinkle-Swift
Questions?