Stress controls heterochromatin inheritance via histone H3 ubiquitylation

Abstract Heterochromatin, marked by histone H3 lysine 9 methylation, can be epigenetically inherited through cell division 1–3 , maintaining gene repression that preserves cell identity and enables adaptation to environmental challenges 2–6 . Studies on S chizosaccharomyces pombe have shown that heterochromatin propagation depends on the read–write mechanism, wherein a sufficient density of H3K9me3-modified nucleosomes, stabilized by histone deacetylases, concentrates Clr4 SUV39H on chromatin to promote further deposition of H3K9 methylation 7–9 . Whether other mechanisms control heterochromatin propagation by means of Clr4 SUV39H , a subunit of the E3 ubiquitin ligase complex ClrC 10–12 , was unknown. Here we…