Fig. 7. Possible mitotic and meiotic cohesin complexes in yeast and mammals. In budding yeast, one of the mitotic cohesin subunits, Scc1p, is replaced by Rec8p in meiosis. In mammals, by contrast, two types of cohesin complex exist in mitosis; their components are SMC1, SMC3, Rad21 and either one of SA1 and SA2. In meiosis, three proteins, SMC1, Rad21 and SA1/SA2, are likely to be replaced by SMC1ß, Rec8 and SA3/SAX (unidentified meiotic SA homolog) in the meiotic cohesin complexes, respectively.