Chapter 13-Cell Biology

Front 1

semi-conservative replication

Back 1

each daughter duplex contains one strand from each parental DNA

Front 2

conservative replication

Back 2

one daughter duplex is only parental DNA and the other is only newly synthesized DNA

Front 3

dispersive replication

Back 3

parental strands are fragmented and new strands are synthesized from them in fragments. Then they join together as a mix.

Front 4

Bidirectional duplication

Back 4

bacterial replication (on a circular chromosome)

Front 5

gyrase

Back 5

bacterial protein that overcomes unwinding problem by breaking and rejoining tightly coiled strand ahead of replication fork relieving tension

Front 6

topoisomerase I/II

Back 6

eukaryotic protein that overcomes unwinding problem by breaking and rejoining tightly coiled strand ahead of replication fork relieving tension.

Front 7

DNA polymerase

Back 7

synthesizes new DNA, requires a single stranded template and a primer

Front 8

okazaki fragments

Back 8

short strands on lagging strand

Front 9

polymerase delta or sometime e

Back 9

type of DNA polymerase in eukaryotic replication

Front 10

polymerase III

Back 10

type of DNA polymerase in bacterial replication

Front 11

primase

Back 11

initiates the synthesis of leading and lagging strands by placing RNA primers (in both bacterial and eukaryotes)

Front 12

polymerase I

Back 12

removes RNA primers in bacteria, and fills gap with DNA

Front 13

DNA ligase

Back 13

seals okazaki fragments into a continuous strand (both bacterial and eukaryotic)

Front 14

primosome

Back 14

is made up of helicase and primase

Front 15

helicase

Back 15

moves along DNA catalyzing the ATP-driven unwinding of duplex.

Front 16

Single-stranded DNA-binding proteins (SSBs)

Back 16

keeps the unwound DNA from reforming

Front 17

5' to 3' exonuclease function

Back 17

removes 10 nucleotides from 5' end which is key to removing RNA primer

Front 18

3' to 5' exonuclease function

Back 18

removes mispaired nucleotides from 3' end of growing DNA and is key to maintaing accuracy of DNA synthesis.

Front 19

B (beta) sliding clamp

Back 19

present in bacterial cells and allows DNA polymerase III to cycle on lagging strand. DNA polymerase III jumps clamp to clamp after each okazaki fragment is finished

Front 20

DNA polymerase III holoenzyme (replisome) is made up of

Back 20

two core polymerases which replicate DNA, two t-subunits which hold the core polymerases in the complex, two or more beta clamps allowing polymerase to stay on DNA, and a clamp loading (gamma) complex which loads each sliding clamp onto DNA.

Front 21

autonomous replicating sequences (ARSs)

Back 21

located in yeast and are sequences that promote replication

Front 22

Origin recognition complex (ORC)

Back 22

recognition of origin of replication (eukaryotes)

Front 23

DnaA

Back 23

recognition of origin of replication (bacteria)

Front 24

Mcm (licensing factor)

Back 24

involved in the steps leading to replication in eukaryotes, binds to origin during or following mitosis. IS A DNA HELICASE THAT UNWINDS PARENTAL DUPLEX (eukaryotes)

Front 25

DnaB

Back 25

DNA helicase that unwinds praental duplex (bacterial)

Front 26

RFC

Back 26

protein that loads the PCNA clamp onto the DNA (eukaryotes)

Front 27

PCNA

Back 27

ring-shaped subunit that clamps replicating polymerase to DNA (eukaryotes).

Front 28

RPA

Back 28

maintains DNA in a single-stranded state (eukaryotes)

Front 29

Fen-1

Back 29

removes RNA primers (eukaryotes)

Front 30

DnaC

Back 30

loads helicase onto DNA (only in bacteria, not sure what does in eukaryotes)

Front 31

replication foci

Back 31

localized sites in nucleus for replication activities

Front 32

nucleosome

Back 32

repeating subunit of chromatin, consists of DNA chain coiled around a core of histones

Front 33

nuclease

Back 33

a repair enzyme that recognizes a mismatched base pair by difference in geometry

Front 34

XPC protein

Back 34

damage recognition in global pathway is mediated by this protein (N.E.R.)

Front 35

CSB protein (cockayne syndrome B)

Back 35

damage recognition in the transcription-coupled pathway is mediated by this protein and a stalled RNA polymerase

Front 36

XPB and XPD proteins

Back 36

two helicase subunits of TFIIH and separate DNA strands (specifically in Nucelotide excision repair)

Front 37

XPG

Back 37

incision on 3' side during nucleotide excision repair

Front 38

XPF-ERRCC1 complex

Back 38

incision on 5' side during nucleotide excision repair

Front 39

DNA glycosylase

Back 39

initiates base excision repair by recognizing a mismatched base and cleaving the glycosidic bond holding the base to the sugar moiety.

Front 40

endonuclease in base excision repair

Back 40

performs the excision of deoxyribose phosphate

Front 41

phosphodiesterase activity in B.E.R.

Back 41

removes sugar-phosphate remnant

Front 42

polymerase B in B.E.R.

Back 42

fills in the gap by inserting complementary nucleotide

Front 43

DNA ligase III

Back 43

sealing step in B.E.R.

Front 44

DNA ligase I

Back 44

sealing step in N.E.R.

Front 45

Ku protein

Back 45

detects lesion in double-strand breaks and binds to the broken ends of DNA

Front 46

DNA-PKcs

Back 46

works with Ku protein to bring broken strands of DNA back together for DNA ligase to seal back together.