RNF8 regulates active epigenetic modifications and escape gene activation from inactive sex chromosomes in post-meiotic spermatids

Genes Dev. 2012 Dec 15;26(24):2737-48. doi: 10.1101/gad.202713.112.

Abstract

Sex chromosomes are uniquely subject to chromosome-wide silencing during male meiosis, and silencing persists into post-meiotic spermatids. Against this background, a select set of sex chromosome-linked genes escapes silencing and is activated in post-meiotic spermatids. Here, we identify a novel mechanism that regulates escape gene activation in an environment of chromosome-wide silencing in murine germ cells. We show that RNF8-dependent ubiquitination of histone H2A during meiosis establishes active epigenetic modifications, including dimethylation of H3K4 on the sex chromosomes. RNF8-dependent active epigenetic memory, defined by dimethylation of H3K4, persists throughout meiotic division. Various active epigenetic modifications are subsequently established on the sex chromosomes in post-meiotic spermatids. These RNF8-dependent modifications include trimethylation of H3K4, histone lysine crotonylation (Kcr), and incorporation of the histone variant H2AFZ. RNF8-dependent epigenetic programming regulates escape gene activation from inactive sex chromosomes in post-meiotic spermatids. Kcr accumulates at transcriptional start sites of sex-linked genes activated in an RNF8-dependent manner, and a chromatin conformational change is associated with RNF8-dependent epigenetic programming. Furthermore, we demonstrate that this RNF8-dependent pathway is distinct from that which recognizes DNA double-strand breaks. Our results establish a novel connection between a DNA damage response factor (RNF8) and epigenetic programming, specifically in establishing active epigenetic modifications and gene activation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Epigenomics*
  • Histones / metabolism
  • Humans
  • Male
  • Meiosis*
  • Nucleic Acid Conformation
  • Protamines / metabolism
  • Sex Chromosomes / metabolism*
  • Spermatids / metabolism
  • Spermatocytes / metabolism
  • Transcriptional Activation*
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism*
  • Ubiquitination
  • X Chromosome Inactivation / genetics

Substances

  • Histones
  • Protamines
  • Rnf8 protein, mouse
  • Ubiquitin-Protein Ligases