Cohesin Complexes: Modulators of Chromatin Organization Control Gene Expression in Immune System (pp. 167-176
Authors: (José L. Barbero, Department of Molecular and Cellular Biology, Chromosome Dynamics in Meiosis Laboratory, Centro de Investigaciones Biológicas (CSIC), Madrid, Spain)
Abstract: Cohesin is a multiprotein, ringed complex that is most well-known for its role in regulating the association/separation of sister chromatids during cell division. However, in the last five years, emerging roles for this interesting protein complex in different DNA dynamic processes have been discovered. Essential functions for cohesin complex have been reported in DNA-damage response and repair, heterochromatin structure, DNA replication and control of gene expression.
Cohesin complex was found to be associated with transcriptional insulators, elements that are linked with the organization of chromatin into regulatory domains. In mammalian cells, cohesin frequently colocalizes with the site-specific zinc finger DNA binding protein CTCF, generating local chromatin structures which regulate long-range interactions between enhancer and promoters. In this sense, recent results indicate specific requirements of cohesins and CTCF-cohesin complexes in several aspects of the immune system physiology.
The molecular structure of cohesin complex, the interaction with other cohesin-interacting proteins and the post-translational modifications of their components are three key pillars in which the chromatin architect functions of cohesin complex are supported.