Distinct functions of S. pombe Rec12 (Spo11) protein and Rec12-dependent crossover recombination (chiasmata) in meiosis I; and a requirement for Rec12 in meiosis II.

ABSTRACT: BACKGROUND: In most organisms proper reductional chromosome segregation during meiosis I is strongly correlated with the presence of crossover recombination structures (chiasmata); recombination deficient mutants lack crossovers and suffer meiosis I nondisjunction. We report that these functions are separable in the fission yeast Schizosaccharomyces pombe. RESULTS: Intron mapping and expression studies confirmed that Rec12 is a member of the Spo11/Top6A topoisomerase family required for the formation of meiotic dsDNA breaks and recombination. rec12-117, rec12-D15 (null), and rec12-Y98F (active site) mutants lacked most crossover recombination and chromosomes segregated abnormally to generate aneuploid meiotic products. Since S. pombe contains only three chromosome pairs, many of those aneu

SUBMITTER: Sharif WD 

PROVIDER: S-EPMC131009 | biostudies-literature | 2002 Sep

REPOSITORIES: biostudies-literature