MSH6

This gene encodes a member of the DNA mismatch repair MutS family. In E. coli, the MutS protein helps in the recognition of mismatched nucleotides prior to their repair. A highly conserved region of approximately 150 aa, called the Walker-A adenine nucleotide binding motif, exists in MutS homologs. The encoded protein heterodimerizes with MSH2 to form a mismatch recognition complex that functions as a bidirectional molecular switch that exchanges ADP and ATP as DNA mismatches are bound and dissociated. Mutations in this gene may be associated with hereditary nonpolyposis colon cancer, colorectal cancer, and endometrial cancer. Transcripts variants encoding different isoforms have been described. [provided by RefSeq, Jul 2013]

MutS Homolog 6

Component of the post-replicative DNA mismatch repair system (MMR). Heterodimerizes with MSH2 to form MutS alpha, which binds to DNA mismatches thereby initiating DNA repair. When bound, MutS alpha bends the DNA helix and shields approximately 20 base pairs, and recognizes single base mismatches and dinucleotide insertion-deletion loops (IDL) in the DNA. After mismatch binding, forms a ternary complex with the MutL alpha heterodimer, which is thought to be responsible for directing the downstream MMR events, including strand discrimination, excision, and resynthesis. ATP binding and hydrolysis play a pivotal role in mismatch repair functions. The ATPase activity associated with MutS alpha regulates binding similar to a molecular switch: mismatched DNA provokes ADP-->ATP exchange, resulting in a discernible conformational transition that converts MutS alpha into a sliding clamp capable of hydrolysis-independent diffusion along the DNA backbone. This transition is crucial for mismatch repair. MutS alpha may also play a role in DNA homologous recombination repair. Recruited on chromatin in G1 and early S phase via its PWWP domain that specifically binds trimethylated 'Lys-36' of histone H3 (H3K36me3): early recruitment to chromatin to be replicated allowing a quick identification of mismatch repair to initiate the DNA mismatch repair reaction.

Determination of adult lifespan Source: BHF-UCL
DNA repair Source: BHF-UCL
Intrinsic apoptotic signaling pathway Source: BHF-UCL
Intrinsic apoptotic signaling pathway in response to DNA damage Source: BHF-UCL
Isotype switching Source: BHF-UCL
Meiotic mismatch repair Source: BHF-UCL
Mismatch repair Source: UniProtKB
Negative regulation of DNA recombination Source: BHF-UCL
Positive regulation of helicase activity Source: BHF-UCL
Response to UV Source: BHF-UCL
Somatic hypermutation of immunoglobulin genes Source: BHF-UCL
Somatic recombination of immunoglobulin gene segments Source: BHF-UCL
Spermatogenesis Source: Ensembl

Nucleus
Other locations
Chromosome
Note: Associates with H3K36me3 via its PWWP domain.

Hereditary non-polyposis colorectal cancer 5 (HNPCC5):
An autosomal dominant disease associated with marked increase in cancer susceptibility. It is characterized by a familial predisposition to early-onset colorectal carcinoma (CRC) and extra-colonic tumors of the gastrointestinal, urological and female reproductive tracts. HNPCC is reported to be the most common form of inherited colorectal cancer in the Western world. Clinically, HNPCC is often divided into two subgroups. Type I is characterized by hereditary predisposition to colorectal cancer, a young age of onset, and carcinoma observed in the proximal colon. Type II is characterized by increased risk for cancers in certain tissues such as the uterus, ovary, breast, stomach, small intestine, skin, and larynx in addition to the colon. Diagnosis of classical HNPCC is based on the Amsterdam criteria: 3 or more relatives affected by colorectal cancer, one a first degree relative of the other two; 2 or more generation affected; 1 or more colorectal cancers presenting before 50 years of age; exclusion of hereditary polyposis syndromes. The term 'suspected HNPCC' or 'incomplete HNPCC' can be used to describe families who do not or only partially fulfill the Amsterdam criteria, but in whom a genetic basis for colon cancer is strongly suspected.
Endometrial cancer (ENDMC):
A malignancy of endometrium, the mucous lining of the uterus. Most endometrial cancers are adenocarcinomas, cancers that begin in cells that make and release mucus and other fluids.
Mismatch repair cancer syndrome 3 (MMRCS3):
An autosomal recessive form of mismatch repair cancer syndrome, a childhood cancer predisposition syndrome encompassing a broad tumor spectrum. This includes hematological malignancies, central nervous system tumors, Lynch syndrome-associated malignancies such as colorectal tumors as well as multiple intestinal polyps, embryonic tumors and rhabdomyosarcoma. Multiple cafe-au-lait macules, a feature reminiscent of neurofibromatosis type 1, are often found as first manifestation of the underlying cancer.
Colorectal cancer (CRC):
A complex disease characterized by malignant lesions arising from the inner wall of the large intestine (the colon) and the rectum. Genetic alterations are often associated with progression from premalignant lesion (adenoma) to invasive adenocarcinoma. Risk factors for cancer of the colon and rectum include colon polyps, long-standing ulcerative colitis, and genetic family history.

The N-terminus is blocked.
Phosphorylated by PRKCZ, which may prevent MutS alpha degradation by the ubiquitin-proteasome pathway.