Surprising New Role For Proteins In Sister Chromatid Cohesion

Scientists reveal a surprising new role for tDNAs and RNA polymerase III-associated proteins in sister chromatid cohesion. Sister chromatid cohesion (the binding together of the two identical copies of each chromosome that are formed during replication) helps to ensure that chromosomes are accurately segregated during the anaphase of the cell cycle. Sister chromatid cohesion is mediated by a multi-subunit protein complex called cohesin. Inside the cell nucleus, cohesin localizes to centromeres (the point of attachment of sister chromatids) as well as heterochromatin (condensed and genetically inactive regions of DNA).