Figure 4.

LAB-1 is present specifically in the interchromatid domain of the bivalent where cohesin protection is required during homolog segregation. LAB-1 and GFP∷AIR-2 localization during meiosis. The top row is a schematic representation of the localization of AIR-2 at different stages of meiosis (green). AIR-2 activity is necessary for the dissociation of subsets of cohesins in the bivalent (first meiotic division) and sister chromatids (second meiotic division and mitosis). As chromosomes separate in anaphase, AIR-2 shuttles to the spindle midzone where it participates in the completion of cytokinesis. During meiosis I, AIR-2-chromosomal localization is restricted to the short arms of the bivalents, in striking contrast to the localization of LAB-1. Bar, 2 μm. Arrows indicate polar bodies.