Cohesinassociated

Cohesin-associated refers to proteins, complexes, and processes connected to the cohesin complex, a multiprotein ring that mediates sister chromatid cohesion and influences chromatin architecture. The term describes factors that load, regulate, or interact with cohesin on chromatin, as well as biological outcomes dependent on cohesin function.

Core cohesin is formed by Smc1, Smc3, Rad21 (also called SCC1), and SA/STAG subunits. A separate loader complex, NIPBL with MAU2, facilitates cohesin loading onto DNA. Regulators include WAPL and PDS5, which promote cohesin release, and Sororin, which helps stabilize cohesion after replication. In mitosis, cohesin’s centromeric cohesion is protected by shugoshin proteins to ensure proper chromosome segregation.

Cohesin-associated activities include establishing sister chromatid cohesion during S phase; organizing chromatin into loops and topologically associating domains; promoting DNA repair through homologous recombination; and influencing gene expression by modulating enhancer-promoter interactions. CTCF, a chromatin architectural protein, often cooperates with cohesin to form chromatin loops.

Abnormal cohesin or its regulators lead to developmental disorders such as Cornelia de Lange syndrome and have been implicated in cancer. Research on cohesin-associated factors relies on chromatin immunoprecipitation, chromosome conformation capture techniques, and genetic models to dissect loading, stabilization, and release mechanisms.