Transient inhibition of histone deacetylation alters the structural and functional imprint at fission yeast centromeres.

Histone acetylation may act to mark and maintain transcriptionally active or inactive chromosomal domains through the cell cycle and in different lineages. A novel role for histone acetylation in centromere regulation has been identified. Exposure of fission yeast cells to TSA, a specific inhibitor of histone deacetylase, interferes with repression of marker genes in centromeric heterochromatin, causes chromosome loss, and disrupts the localization of Swi6p, a component of centromeric heterochromatin. Transient TSA treatment induces a heritable hyperacetylated state in centromeric chromatin that is propagated in lineages in the absence of drug. This state is linked in cis to the treated centromere locus and correlates with inheritance of functionally defective centromeres and persistent chromosome segregation problems. Thus, assembly of fully functional centromeres is partly imprinted in the underacetylated or transcriptionally silent state of centromeric chromatin.