The centromere
Centromeres are chromosomal loci that assemble the proteinaceous kinetochore, maintain sister chromatid cohesion, regulate chromosome attachment to the spindle, and direct chromosome movement during cell division. Although the function of centromeres and proteins that contribute to their complex structure are conserved in eukaryotes, centromeric DNAs are strikingly divergent. In this chapter, I review centromere organization in a range of organisms, including unicellular eukaryotes, fruit flies, plants, and mammals. Sequence features and epigenetic mechanisms of centromere identity and regulation, including DNA-protein interactions, post-translational modifications, RNA, and protein dosage that influence centromere-specific chromatin architecture are discussed. Understanding the assembly and organization of centromeres and the contributions of sequence and epigenetic features in centromere identity and diversity remain important areas of study in chromosome biology. © 2009 Springer Science+Business Media, LLC.
