Middle HEAT-repeat binding domain of Rad21/Rec8-like proteins
This family includes eukaryotic cohesins of the Rad21, Rec8, and Scc1 subfamilies. They mediate sister chromatid cohesion during mitosis and meiosis, as part of the cohesin complex. Cohesion is necessary for homologous recombination (including double-strand break repair) and correct chromatid segregation. These proteins may also be involved in chromosome condensation. Dissociation at the metaphase to anaphase transition causes loss of cohesion and chromatid segregation. This model corresponds to a conserved middle/central region of family members, consisting of short helices and two extended segments, which functions in binding to HEAT-repeat containing cohesin subunits. For example, human Scc1 homolog (NXP-1) binds to either SA1 or SA2, two homologous HEAT-containing proteins; the SA-Scc1 heterodimer mediates the binding between cohesin and its regulators, including Scc2-Scc4, Pds5, Wapl, and Sgo1.
Jiyao W et al.(2023). "The conserved domain database in 2023.",