Fig. 1. Chromosome segregation in mitosis and meiosis. Sister chromatid cohesion during mitosis, carried out by Rad21/Scc1 complexes, is lost along the whole chromosome length at anaphase. During meiosis, Rec8 substitutes for the Rad21/Scc1 subunit of the cohesin complex. Consequently, sister chromatid cohesion is lost in a stepwise manner, first along chromosome arms during meiosis I and second in the vicinity of centromeres during meiosis II.