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Expanded roles for the MutL family of DNA mismatch repair proteins.

ABSTRACT: The MutL family of DNA mismatch repair proteins plays a critical role in excising and repairing misincorporation errors during DNA replication. In many eukaryotes, members of this family have evolved to modulate and resolve recombination intermediates into crossovers during meiosis. In these organisms, such functions promote the accurate segregation of chromosomes during the meiosis I division. What alterations occurred in MutL homolog (MLH) family members that enabled them to acquire these new roles? In this review, we present evidence that the yeast Mlh1-Mlh3 and Mlh1-Mlh2 complexes have evolved novel enzymatic and nonenzymatic activities and protein-protein interactions that are critical for their meiotic functions. Curiously, even with these changes, these complexes retain backup and accessory roles in DNA mismatch repair during vegetative growth.

SUBMITTER: Furman CM

PROVIDER: S-EPMC7854849 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Expanded roles for the MutL family of DNA mismatch repair proteins.

Furman Christopher M CM Elbashir Ryan R Alani Eric E

Yeast (Chichester, England) 20200730 1

The MutL family of DNA mismatch repair proteins plays a critical role in excising and repairing misincorporation errors during DNA replication. In many eukaryotes, members of this family have evolved to modulate and resolve recombination intermediates into crossovers during meiosis. In these organisms, such functions promote the accurate segregation of chromosomes during the meiosis I division. What alterations occurred in MutL homolog (MLH) family members that enabled them to acquire these new ...[more]

PMID: 32652606

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