The length of duplex DNA that usually is unwound to initiate replicati011 is probably <60 bp.

TLS Online TPP Program

#Id: 6117

#Unit 3. Fundamental Processes

Longer mismatches (2 to 6 bp) recognized by heterodimer of MSH2 and MSH3.  Homologs of MutL, predominantly a heterodimer of MLH1 (MutL homolog) and PMS1 (post-meiotic segregation), bind to and stabilize the MSH complexes

TLS Online TPP Program

#Id: 6118

#Unit 3. Fundamental Processes

The hMutb complex, a Msh2-Msh3 dimer, binds mismatched insertion/deletion/slippage loops, while the Msh2-Msh6 (hMuta) complex binds to single-base mismatches.

TLS Online TPP Program

#Id: 6119

#Unit 3. Fundamental Processes

Mutations in MutS/L components can lead to hereditary nonpolyposis colorectal cancer (HNPCC). A characteristic feature of HNPCC is microsatellite instability, in which the lengths (numbers of repeats) of microsatellite sequences change rapidly in the tumor cells due to the loss of the mismatch repair system to correct replication slippage in these sequences.

TLS Online TPP Program

#Id: 6120

#Unit 3. Fundamental Processes

Eukaryotic cells lack MutH and uses Okazaki fragments nick to recognise daughter starnds

TLS Online TPP Program

#Id: 6121

#Unit 3. Fundamental Processes

The MutT, -M, -Y system handles the consequences of oxidative damage. Major type of chemical damage is caused by oxidation of G to 8-oxo-G

TLS Online TPP Program

#Id: 6122

#Unit 3. Fundamental Processes

The deamination generates a G-T/C-T mismatch pair, MutL and MutS remove T from both G-T and C-T mismatches.