MSH2 shapes the meiotic crossover landscape in relation to interhomolog polymorphism in Arabidopsis.

ABSTRACT: During meiosis, DNA double-strand breaks undergo interhomolog repair to yield crossovers between homologous chromosomes. To investigate how interhomolog sequence polymorphism affects crossovers, we sequenced multiple recombinant populations of the model plant Arabidopsis thaliana. Crossovers were elevated in the diverse pericentromeric regions, showing a local preference for polymorphic regions. We provide evidence that crossover association with elevated diversity is mediated via the Class I crossover formation pathway, although very high levels of diversity suppress crossovers. Interhomolog polymorphism causes mismatches in recombining molecules, which can be detected by MutS homolog (MSH) mismatch repair protein heterodimers. Therefore, we mapped crossovers in a msh2 mutant, defective i

SUBMITTER: Blackwell AR 

PROVIDER: S-EPMC7604573 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature