description
MSH2:MSH3 (MutSbeta) binds unpaired loops of 2 or more nucleotides (Palombo et al. 1996, Genschel et al. 1998). Human cells contain about 6-fold more MSH2:MSH6 than MSH2:MSH3 (MutSbeta) and an imbalance in the ratio can cause a mutator phenotype (Drummond et al. 1997, Marra et al. 1998). Binding of the mismatch activates MSH2:MSH3 to exchange ADP for ATP, adopt the conformation to allow movement along the DNA, and interact with downstream effectors PCNA, MLH1:PMS2 and EXO1. The interaction with PCNA initiates excision of the recently replicated strand. MLH1:PMS2 makes a nick that is enlarged to a gap of hundreds of nucleotides by EXO1. DNA is polymerized across the gap by DNA polymerase delta and the remaining nick is sealed by DNA ligase I

external resources
NCBI:1270413
REACTOME:R-HSA-5358606
PUBMED:9677427
PUBMED:11920679
PUBMED:9294177
PUBMED:9671718
PUBMED:8805365

genes
LIG1 , MLH1 , MSH2 , MSH3 , PCNA , PMS2 , POLD1 , POLD2 , RPA1 , RPA2 , RPA3 , EXO1 , POLD3 , POLD4 ,