While DnaA has a weak intrinsic activity that converts the ATP to ADP, this is enhanced by a factor termed Hda.

TLS Online TPP Program

#Id: 6115

#Unit 3. Fundamental Processes

TLS Online TPP Program

#Id: 6116

#Unit 3. Fundamental Processes

The main MutS homologs in most eukaryotes are MSH2 (MutS homolog), MSH3, and MSH6.

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