Yeast X-chromosome-associated protein 5 (Xap5) functions with H2A.Z to suppress aberrant transcripts

EMBO Rep. 2014 Aug;15(8):894-902. doi: 10.15252/embr.201438902. Epub 2014 Jun 23.


Chromatin regulatory proteins affect diverse developmental and environmental response pathways via their influence on nuclear processes such as the regulation of gene expression. Through a genome-wide genetic screen, we implicate a novel protein called X-chromosome-associated protein 5 (Xap5) in chromatin regulation. We show that Xap5 is a chromatin-associated protein acting in a similar manner as the histone variant H2A.Z to suppress expression of antisense and repeat element transcripts throughout the fission yeast genome. Xap5 is highly conserved across eukaryotes, and a plant homolog rescues xap5 mutant yeast. We propose that Xap5 likely functions as a chromatin regulator in diverse organisms.

Keywords: aberrant transcripts; chromatin modification; long terminal repeats; transcriptional repression; transposable elements.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Antisense Elements (Genetics)
  • Arabidopsis / genetics
  • Arabidopsis Proteins / genetics
  • DNA-Binding Proteins / physiology*
  • Genes, Fungal
  • Genetic Complementation Test
  • Histones / physiology*
  • Protein Binding
  • RNA, Fungal / genetics
  • RNA, Fungal / metabolism
  • RNA, Messenger / metabolism
  • Repetitive Sequences, Nucleic Acid
  • Schizosaccharomyces / genetics*
  • Schizosaccharomyces / metabolism
  • Schizosaccharomyces pombe Proteins / physiology*
  • Transcription, Genetic
  • Up-Regulation


  • Antisense Elements (Genetics)
  • Arabidopsis Proteins
  • DNA-Binding Proteins
  • Histones
  • PHT1 protein, S pombe
  • RNA, Fungal
  • RNA, Messenger
  • Schizosaccharomyces pombe Proteins
  • Xap5 protein, S pombe