The Mutability and Repair of DNA

1
The Mutability and Repair of DNA
Two main types of DNA damage point
mutations structural mutations
The molecular basis of point mutations
1. Base substitution transition transversion
2. Frame shift
3. Tautomeric shift
2
Gene Mutation
The molecular basis of point mutations
4. Base analogs and chemical mutagens
3
Gene Mutation
The molecular basis of structural damage
1. Hydrolytic damage
Deamination
N-glycosidic bond very weak and easily broken
Depurination
Deamination
4
Gene Mutation
The molecular basis of structural damage
2. Alkylation, Oxidation and Radiation
5
Gene Mutation
DNA Repair
1. Mismatch repair
Dam methylase
MutS
6
Gene Mutation
DNA Repair
1. Mismatch repair
7
Gene Mutation
DNA Repair
2. Photoreactivation
8
Gene Mutation
DNA Repair
3. Base excision repair
9
Gene Mutation
DNA Repair
3. Base excision repair
10
Gene Mutation
4. Nucleotide excision repair
11
Gene Mutation
4. Nucleotide excision repair
Transcription coupled DNA repair
12
Gene Mutation
5. Post-replication repair (recombination repair)
6. Translesion DNA synthesis/ Inducible repair or
SOS response
recombined