Middle HEAT-repeat binding domain found in Homo sapiens meiotic recombination protein REC8 homolog and similar proteins
Rec8, also called cohesin Rec8p, is a meiotic recombination and sister chromatid cohesion phosphoprotein of the Rad21p family conserved from fission yeast to humans. It is required during meiosis for separation of sister chromatids and homologous chromosomes. Proteolytic cleavage of Rec8 on chromosome arms by separin during anaphase I allows for homologous chromosome separation in meiosis I, and cleavage of Rec8 on centromeres during anaphase II allows for sister chromatid separation in meiosis II. This model corresponds to a small region in the middle of Rec8 that shows high sequence similarity with the HEAT-repeat binding domain found in both the middle of Saccharomyces cerevisiae sister chromatid cohesion protein 1 (ScScc1p) and Homo sapiens nuclear matrix protein 1 (NXP-1), which consists of short helices and two long extended segments.
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