Chapter 14: Mutation & repair Fig. 14-1

Dose-dependent induction of mutation by X-rays Fig. 14-2

Fig. 14-3

Consequences of mutations on RNA and protein Fig. 14-4

Normal keto tautomers Standard base pairing Fig. 14-5

Normal keto tautomers Standard base pairing Rare tautomers Alternative base pairing Fig. 14-5 & 6

Some analogs increase tautomeric shifts Fig. 14-7 & 8

Alkylated bases have altered pairing possibilities Fig. 14-9

Classic frameshift mutagens Fig. 14-10

Classic frameshift mutagens Fig. 14-10

UV-induced pyrimidine crosslinks Fig. 14-12

Potent carcinogen Synthesized by fungus grown on peanuts Fig. 14-13 & 14

Spontaneous mutations by deamination Fig. 14-18

Producing mutation “hotspots” at 5-methyl cytosine sites Fig. 14-19

Spontaneous mutation by replication of repeated nucleotide motifs (frameshift mutations) Fig. 14-21

Resulting in clustered occurrence of frameshifts Fig. 14-22

DNA repair systems Direct repair of lesion General excision repair Specific excision repair ds-DNA end-joining Post-replication repair

General types of nucleotide repair Fig. 14-25

Photo-activated thymine dimer repair Fig. 14-26

Depurination-activated excision repair (AP site repair) Fig. 14-27

Nucleotide excision repair Fig. 14-28

Repair of double-strand breaks: nonhomologous end-joining (non-dividing cells) Error-prone repair Fig. 14-32

Repair of double-strand breaks: homologous recombination (dividing cells) Error-free repair Fig. 14-33

Fig. 14-