Biology Project OverviewBiology Project Overview

Comparisons of GAPC Gene Comparisons of GAPC Gene Organization in PlantsOrganization in Plants

GAPC GeneGAPC Gene• Codes for the enzyme: Glyceraldehyde-3-Phosphate Codes for the enzyme: Glyceraldehyde-3-Phosphate

Dehydrogenase (Cytosolic)Dehydrogenase (Cytosolic)• Gene is found in the cell nucleus Gene is found in the cell nucleus • Member of a Gene Family Member of a Gene Family

– 4 genes in the thale cress plant 4 genes in the thale cress plant Arabidopsis, Arabidopsis, a member of a member of the mustard plant familythe mustard plant family

– GAPC and GAPC-2 code for enzymes that act in the cell GAPC and GAPC-2 code for enzymes that act in the cell cytoplasmcytoplasm

– GAPCP-1 and GAPCP-2 code for enzymes that act in the GAPCP-1 and GAPCP-2 code for enzymes that act in the chloroplastschloroplasts

GAPC Gene ProductGAPC Gene Product• Enzyme (gene product) works in the cell Enzyme (gene product) works in the cell

cytoplasmcytoplasm• Reaction: Reaction:

• NADH is an electron carrier that donates electrons NADH is an electron carrier that donates electrons to the Mitochondrial Electron Transport Chain for to the Mitochondrial Electron Transport Chain for production of ATPproduction of ATP

• ATP (Adenosine Triphosphate) provides energy ATP (Adenosine Triphosphate) provides energy for most endergonic biological reactionsfor most endergonic biological reactions

NAD+ (Nicotine Adenine Dinucleotide) accepts one proton and two electrons to

become NADH

Glyceraldehyde-3-Phosphate

Dehydrogenase is the catalyst

Using Polymerase Chain Reaction (PCR)Using Polymerase Chain Reaction (PCR)

• PCR is a highly accurate and efficient way of copying PCR is a highly accurate and efficient way of copying (amplifying) a specific region of DNA for study(amplifying) a specific region of DNA for study

• The process involves specific primers that attach to the end of The process involves specific primers that attach to the end of the target sequence and serve as starting points for elongationthe target sequence and serve as starting points for elongation

• Heating and cooling cycles provide multiple rounds of PCR Heating and cooling cycles provide multiple rounds of PCR where the template number doubles with each round where the template number doubles with each round

• Taq polymerase, a heat-stable enzyme that catalyzes DNA Taq polymerase, a heat-stable enzyme that catalyzes DNA synthesis, is used to produce the DNA copiessynthesis, is used to produce the DNA copies

Using Polymerase Chain Reaction (PCR)Using Polymerase Chain Reaction (PCR)

• Starting with a single copy of a DNA sequence, over 1 million Starting with a single copy of a DNA sequence, over 1 million copies can be generated with about 30 rounds of PCRcopies can be generated with about 30 rounds of PCR

• In the Biology Research Project, students will amplify the In the Biology Research Project, students will amplify the nuclear gene for glyceraldehyde phosphate dehydrogenase nuclear gene for glyceraldehyde phosphate dehydrogenase (GAPC) from a variety of plants, with a “nested” procedure (GAPC) from a variety of plants, with a “nested” procedure using two sequential sets of primers to enhance specificityusing two sequential sets of primers to enhance specificity

Using Polymerase Chain Reaction (PCR)Using Polymerase Chain Reaction (PCR)

Inner Arrows show position of primers for

PCR Round 2

Outer Arrows show position of primers for

PCR Round 1

Sizes of DNA Products can be determined by

agarose gel electrophoresis

GAPC gene PCR product is missing one intron

(interruption) found in the other three genes

Comparing Round 1 and Round 2 ResultsComparing Round 1 and Round 2 ResultsS

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ROUND 2ROUND 2

Join the Join the

Biology Research Project if You:Biology Research Project if You:

• Are interested in applying molecular Are interested in applying molecular biology techniquesbiology techniques– Polymerase Chain ReactionPolymerase Chain Reaction– Agarose Gel Electrophoresis Agarose Gel Electrophoresis

• Would like to explore evolutionary Would like to explore evolutionary relationships relationships – Sizing DNA FragmentsSizing DNA Fragments– Bioinformatics of Sequence DataBioinformatics of Sequence Data