-
Homologus recombination step by step.
- (During S and G2 phases)
- 1. endonuclease chews ends of DNA to make strand excision.
- 2. homology search via strand invasion.
- 3. d-loop formation
- 4. DNA poly fills in DNA using sister chromatid as template.
- 5. DNA ligase fixes backbone
-
NHEJ process step by step
- (During G1 phase, no homologus template available here)
- 1. Ku protein binds
- 2. DNA-pk binds and autophosphorolate brings ends together.
- 3. Regions of microhomology are found when DNA-pk phosphorolates Ku, and Ku has helicase activity.
- 4. Base pairing occurs
- 5. Flaps removed by nucleases
- 6. Gaps filled in.
- DNA ligase fixes backbone.
-
Mismatch repair process step by step
- (when replication error occurs)
- 1. GATC (A methylated) recognized by system.
- 2. Bases recognized by Mut H, MutL, MutS
- 3. Helicase helps unwind DNA
- 4. exonuclase 1 cleaves out daughter strand
- 5. DNA poly 3 fills in missing gaps.
- 6. DNA ligase fixes backbone.
- 7. Daughter strand is methylated.
-
BER process step by step (prokaryote)
- 1. DNA base extrusion by DNA glycoslase
- 2. DNA glycosylase removes base
- 3. AP site
- 4. AP endonucleases nick/cut backbone DNA
- 5. DNA phosphodiesterase removes phosphate
- 6. DNA poly 1 replaces nucleotide.
- 7. DNA ligase fixes backbone.
-
Prokaryotic NER process step by step
- 1. Excinuclease removes bases around damage
- 2. DNA poly 1 fills in gap.
- 3. DNA ligase fixes backbone.
-
high salt concentration denatures DNA t/f?
F
-
RNA coeficient is 50ug/ml t/f
F
-
name of bond that binds two nucleotides
phosphodiester
-
plasmid vectors should have origin of transcription?
False. Origin of replication.
-
Investigate effects of gene, want to see how much it is expressed in tissues, which technique do you use?
Northern blot
-
when gene is inserted into frame of another gene it makes a what?
fusion protein
-
reporter genes are used to see when genes are expressed at any given time, t/f.
T
-
which technique would you use to fill in missing pieces of cDNA after making a cDNA library?
RACE
-
sds PAGE seperates proteins based on?
Size
-
What technique would you use to determine if protein x binds to protein y?
co-immunoprecipitation
-
Reverse transcriptase makes a identical copy of DNA from template RNA, t/f?
F, it makes a complement DNA.
-
What should colony color be if you interupt lacz gene and plate on x-gal?
white
-
eukaryotic NER requires function of a general transcription factor. t/f
T
-
what kind of coils does gyrase pump into strand?
negative
-
BER fights damage done by alkylating agents, t/f?
T
-
what label was used to determine bi-directioanlity of replication?
radiated thymadine
-
MutH, MutL, MutS are proteins involved in mismatch repair, t/f.
T
-
Dna glycosylase is key enzyme in BER, t/f.
T
-
how long are okazaki fragments roughly, before they are ligated together?
1000-2000bases
-
DNA primers are used during DNA replication, t/f.
F
-
translesion synthesis leads to errors in newly replicated strand. t/f
T
-
Nucleotide excision repair fixes damage done by 6,4-pp's. T/F.
T
-
replication errors are fixed by which mechanism?
Mismatch
-
APE1 proofreads errors during replication repair, t/f?
F
-
Klenow fragment of DNA poly 1 has exonuclease activity, t/f.
F
-
when does recombination repair occur?
during replication when sister chromatids are present. S and G2
|
|
