The centromere is a chromatin region that serves as the spindle attachment point and directs accurate inheritance of eukaryotic chromosomes during cell divisions. However, the mechanism by which the centromere assembles and stabilizes at a specific genomic region is not clear. The de novo formation of a human/mammalian artificial chromosome (HAC/MAC) with a functional centromere assembly requires the presence of alpha-satellite DNA containing binding motifs for the centromeric CENP-B protein. We demonstrate here that de novo centromere assembly on HAC/MAC is dependent on CENP-B. In contrast, centromere formation is suppressed in cells expressing CENP-B when alpha-satellite DNA was integrated into a chromosomal site. Remarkably, on those integration sites CENP-B enhances histone H3-K9 trimethylation and DNA methylation, thereby stimulating heterochromatin formation. Thus, we propose that CENP-B plays a dual role in centromere formation, ensuring de novo formation on DNA lacking a functional centromere but preventing the formation of excess centromeres on chromosomes. © 2007 Elsevier Inc. All rights reserved.
Okada, T., Ohzeki, J. ichirou, Nakano, M., Yoda, K., Brinkley, W. R., Larionov, V., & Masumoto, H. (2007). CENP-B Controls Centromere Formation Depending on the Chromatin Context. Cell, 131(7), 1287–1300. https://doi.org/10.1016/j.cell.2007.10.045