Evolutionary origin, diversification and specialization of eukaryotic MutS homolog mismatch repair proteins
AUTOR(ES)
Culligan, Kevin M.
FONTE
Oxford University Press
RESUMO
Most eubacteria, and all eukaryotes examined thus far, encode homologs of the DNA mismatch repair protein MutS. Although eubacteria encode only one or two MutS-like proteins, eukaryotes encode at least six distinct MutS homolog (MSH) proteins, corresponding to conserved (orthologous) gene families. This suggests evolution of individual gene family lines of descent by several duplication/specialization events. Using quantitative phylogenetic analyses (RASA, or relative apparent synapomorphy analysis), we demonstrate that comparison of complete MutS protein sequences, rather than highly conserved C-terminal domains only, maximizes information about evolutionary relationships. We identify a novel, highly conserved middle domain, as well as clearly delineate an N-terminal domain, previously implicated in mismatch recognition, that shows family-specific patterns of aromatic and charged amino acids. Our final analysis, in contrast to previous analyses of MutS-like sequences, yields a stable phylogenetic tree consistent with the known biochemical functions of MutS/MSH proteins, that now assigns all known eukaryotic MSH proteins to a monophyletic group, whose branches correspond to the respective specialized gene families. The rooted phylogenetic tree suggests their derivation from a mitochondrial MSH1-like protein, itself the descendent of the MutS of a symbiont in a primitive eukaryotic precursor.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=102523Documentos Relacionados
- Mutation detection with MutH, MutL, and MutS mismatch repair proteins.
- Mismatch repair proteins MutS and MutL inhibit RecA-catalyzed strand transfer between diverged DNAs.
- Mutations in the DNA Mismatch Repair Proteins MutS and MutL of Oxazolidinone-Resistant or -Susceptible Enterococcus faecium
- The alternating ATPase domains of MutS control DNA mismatch repair
- Interaction of MutS and Vsr: Some Dominant-Negative mutS Mutations That Disable Methyladenine-Directed Mismatch Repair Are Active in Very-Short-Patch Repair