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Centromeres license the mitotic condensation of yeast chromosome arms

ABSTRACT: During mitosis, chromatin condensation shapes chromosomes as separate, rigid and compacted sister-chromatids to facilitate their segregation. Here, we show that unlike wild type yeast chromosomes, non-chromosomal DNA circles and chromosomes lacking a centromere fail to condense during mitosis. Genetics and ChIP-seq experiments establish that the centromere functions in chromosome condensation upstream of the kinases Aurora B and Bub1. Downstream of Aurora B and Bub1, Shugoshin and the deacetylase Hst2 facilitated spreading of the condensation signal from the pericentromeric region to the chromosome arms. Targeting Aurora B to DNA circles or centromere-ablated chromosomes, or releasing Shugoshin from PP2A-dependent inhibition bypassed the centromere requirement for condensation and enhanced the mitotic stability of DNA circles. Our data indicate that yeast cells license in a centromere-dependent manner the chromosome-autonomous condensation of their chromatin, excluding non-centromeric DNA from this process and thereby inhibiting their propagation.

ORGANISM(S): Saccharomyces cerevisiae

PROVIDER: GSE100643 | GEO | 2018/10/11

REPOSITORIES: GEO

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