DNA Replication, Mutation, and Repair

Question 1

Cyclin and Kinase that leads to Progression past the (G1) Restriction Point at the G1 / S boundary

Answer 1

Cyclin: D
Kinase: CDK4, CDK6

Question 2

Cyclin and Kinase that leads to the initiation of DNA synthesis in Early S Phase

Answer 2

Cyclin: E. A
Kinase: CDK 2

Question 3

Cyclin and Kinase that leads to the transition from G2 to M phase

Answer 3

Cyclin: B
Kinase: CDK1

Question 4

Involves the removal of an amine group from the DNA base

Answer 4

Deamination

Question 5

Deamination causes unnatural DNA bases through a reaction with ___

Answer 5

H2O

Question 6

Unnatural bases
Adenine -> ____
Guanine -> ____
Cytosine -> ____

Answer 6

Hypoxanthine
Xanthine
Uracil

Question 7

Involves the removal of a purine from the DNA base through hydrolysis

Answer 7

Depurination

Question 8

Alkylating agents can add a methyl or ethyl group to a nitrogenous base

Answer 8

Alkylation of Base

Question 9

Nitrogen, sulfur mustard, methyl and ethyl methane sulfonate are examples of

Answer 9

Alyklating Agents

Question 10

Can lead to transition, transversion, and frame shift mutations

Answer 10

Alkylation of Base

Question 11

Interchange of a purine to another purine, or of a

pyrimidine to another pyrimidine in DNA (similar bases)

Answer 11

Transition

Question 12

interchange of a pyrimidine to a purine or of a purine to a pyrimidine in DNA (dissimilar bases)

Answer 12

Transversion

Question 13

a mutation caused by insertion or deletion of bases that alters the reading frame for codons

Answer 13

Frame Shift Mutatioon

Question 14

Derivatives of normal bases are incorporated into the DNA

Answer 14

Base-Analog Incorporation

Question 15

5-bromouracil, 2-aminopurine, 6-mercaptopurine, and acycloguanosine
are examples of

Answer 15

Base-Analogs

Question 16

____are molecules that take the place of the normal nitrogenous
bases in DNA (A, T, C, G)

Answer 16

Base analogs

Question 17

What causes linkage of adjacent thymine bases along the DNA strand? Type of damage?

Answer 17

UV Light; Thymine-Thymine dimers

Question 18

Alkylating agents that can cause cross-linkages that are either interstrand or intrastrand

Answer 18

Bifunctional Alkylating Agent Cross-Linkage

Question 19

chemotherapeutic drugs such as cyclophosphamide are an example of

Answer 19

Bifunctional alkylating agents

Question 20

an cause single strand or double strand breaks due to ionizing radiation, radioactive disintegration of backbone element, and oxidative free radical formation

Answer 20

Chain breaks

Question 21

Examples of this cause of chain break are gamma rays, x-rays that sever strands

Answer 21

ionizing radiation

Question 22

What can oxidative free radical formation do?

Answer 22

Can modify purines, creating 8-hydroxy-deoxyguanosine

Question 23

Marker of oxidative damage to DNA

Answer 23

8-OH-dG

Question 24

Cross linkages can happen between three things

Answer 24

Intrastrand, Interstrand, Between DNA and protein molecues

Question 25

A chromosomal abnormality wherein there’s a break in one particular chromosome, and that chromosome will then fuse to a different chromosome, which will lead to what we call a fusion product

Answer 25

Translocations Sometimes pieces from two different chromosomes will trade places with each other (National Cancer Institute, n.d.) • May lead to medical problems such as leukemia, breast cancer, schizophrenia, muscular dystrophy and Down Syndrome (National Cancer Institute, n.d.)

Question 26

A molecular process that increases the number of copies of a gene sequence without a proportional increase in the other genes

Answer 26

Gene Amplification

Question 27

Gene amplification leads to (2)

Answer 27

− Overproduction of the protein (Alberts, et al., 2015) − Enhanced expression of the genes in the amplified portion (Mondello, et al., 2010) plays an important role in cancer

Question 28

proteins that identify damages or breaks in the DNA

Answer 28

sensors

Question 29

phosphorylates mediator or effector proteins to influence cell activity

Answer 29

transducers

Question 30

intermediary proteins for repair response

Answer 30

mediators

Question 31

dictate and carry out the ultimate outcomes of DNA damage response

Answer 31

effectors

Question 32

A potent CDK-Cyclin inhibitor which causes cell cycle arrest

Answer 32

p21

Question 33

Effectors of cell death (apoptosis)

Answer 33

PUMA, BAX, and NOVA

Question 34

An effector for cell aging (senescence)

Answer 34

Cell aging (senescense)

Question 35

Recognition of distortion in DNA by ___ → ____ dsDNA into ssDNA and removes affected area → ____ adds bases through addition of phosphodiester bonds → ____seals the nick between the new nucleotides and the old strand what type of repair?

Answer 35

uvrA, helicasel dna polymerasel dna ligase; Nucleotide Excision Repair

Question 36

Damaging agent of Nucelotide Excision Repair

Answer 36

UV light chemicals

Question 37

Corrects a single mismatched base pair

Answer 37

Mismatch repair

Question 38

____ recognizes mismatched base pair → ____ removes area of mismatch → ____ adds bases through addition of phosphodiester bonds → ____ seals the nick what type of repair?

Answer 38

MutS Protein; Exonuclease; DNA Polymerase; DNA ligase; mismatch repair

Question 39

Damaging agent of mismatch repair

Answer 39

replication errors

Question 40

Single base repair

Answer 40

base excision repair

Question 41

____ recognize the damaged base and remove it → ____ recognize the site with a missing base → AP Endonuclease cleaves the sugar-phosphate backbone → ____ removes the sugar-phosphate that lacks the base → ____ repairs the damaged DNA → ____ seals the nick what type of repair?

Answer 41

DNA glycosylases ; AP | endonucleases; Deoxyribose phosphodiesterase; DNA polymerases; DNA ligase ; base excision repair

Question 42

Damaging agent of Base Excision Repair

Answer 42

oxygen radicals, hydrolysis, alkylating agents (Rodwell et al., 2018)

Question 43

• For cells in the S and G2 phases of the cell cycle • There is a need for the daughter strands to repair the double strand breaks of the parent strand

Answer 43

Homologous recombination

Question 44

Damaging agent of Homologous Recombination

Answer 44

ionizing radiation, x-rays, anti-tumor drugs (Rodwell et al., 2018)

Question 45

cross linking of the daughter strands with the parent strand

Answer 45

holliday junction

Question 46

Used during the G0 and G1 phase of the cell cycle | • Does not require the daughter strands for damage repair

Answer 46

Non-homologous end joining • Has the least fidelity

Question 47

____binds around the broken ends → Ku recruits DNA PKcs which recruits the protein artemis and phosphorylates it → artemis trims residual single stranded tails from the break → ligase IV joins the broken ends together what type of repair

Answer 47

Ku proteins; non homologous end joining