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Flashcards in DNA Replication Deck (32):
1

enzyme that builds DNA

DNA polymerase

2

What is the type of replication DNA undergoes?

Semi-conservative

3

experiment that proved type of replication DNA undergoes

Meselson and Stahl
uses CsCl gradient
used heavy 15N nitrogen to grow bacteria. then placed in light 14N nitrogen and replication is done. strands became lighter leaving bands in centrifugation

4

name of DNA strands during replication

leading strand and lagging strand

5

fragments on lagging strand

Okazaki fragments

6

DNA polymerase resembles a

right hand

7

DNA polymerase alpha

eukaryotic DNA replication initiation

8

DNA polymerase delta

eukaryotic DNA replication, lagging strand

9

DNA polymerase epsilon

eukaryotic DNA replication, leading strand

10

what is the fidelity of dNA replication?

1 mistake in 10^9 nucleotides

11

extremely important for fidelity

proofreading

12

Direction of proofreading?

goes in "opposite" direction. 3'-5'

13

proofreading exonuclease has _____ active sites

2 active sites, P and E
polymerase catalytic site
exonuclease catalytic site

14

fidelity of DNA polymerase

1 in 10^5

15

fidelity of DNA proofreading

1 in 10^2

16

fidelity of DNA strand-directed mismatch repair

1 in 10^2

17

primase

creates 10 nucleotide primer
uses RNA
in eukaryotes, its par of DNA polymerase alpha complex

18

lagging strand has primers every _____

100-200 nucleotides

19

in eukaryotes the RNA primer is removed by

flap endonuclease

20

closes gaps and nicks in DNA

DNA ligase I

21

unwinds the DNA double helix

DNA helicase
named for the direction they move across the strand

22

what is DNA helicase made of

MCM2-7 hexamer complex

23

proteins that bind to single-stranded DNA

Eukaryotes- RPA (3 sub-units)

24

sliding clamp name and function

DNA polymerase attaches to sliding clamp,
eukaryotes- homotrimer named PCNA

25

alt name for sliding clamp

processivity factor

26

sliding clamps bring

MANY different enzymes to the replication fork.
DNA ligase, flap endonuclease, repair systems, and chromatin assembly factors

27

sliding clamps are loaded by

clamp loaders
eukaryotes, called RFC or replication factor-C

28

clamp loaders require _______

ATP in order to load the sliding clamp

29

enzymes that relieve super-twisting caused by unwinding and rewinding DNA

type I topoisomerase

30

how does type I topoisomerase work

creates a nick in the DNA allowing it to rotate to relieve stress.
reaction is reversible

31

can make double stranded breaks in DNA when DNA is tangled

Type II topoisomerase

32

activities listed for DNA replication fork

1. Synthesis- sliding clamp and DNA polymerase
2. Unwinding- DNA helicase
3. Untwist DNA- topoisomerase
4. Priming- RNA primase, flap endonuclease to remove
5. Seal DNA- ligase to close nicks
6. Protection SSD- single-stranded binding proteins