<p>STAG domain proteins are subunits of cohesin complex - a protein complex required for sister chromatid cohesion in eukaryotes. The STAG domain is present in <taxon tax_id="4896">Schizosaccharomyces pombe</taxon> (Fission yeast) mitotic cohesin Psc3, and the meiosis specific cohesin Rec11. Many organisms express a meiosis-specific STAG protein, for example, mice and humans have a meiosis specific variant called STAG3, although budding yeast does not have a meiosis specific version [<cite idref="PUB00020823"/>]. </p>