Negative regulation of JAK2 by H3K9 methyltransferase G9a in leukemia

Mol Cell Biol. 2012 Sep;32(18):3681-94. doi: 10.1128/MCB.00673-12. Epub 2012 Jul 16.

Abstract

Histone methylation at specific lysine residues is a crucial regulatory process in transcriptional regulation. Using chromatin immunoprecipitation with microarray technology (ChIP-chip) analysis, we found that the H3K9-me2 target gene JAK2 was an important factor during differentiation of the HL-60 promyelocytic leukemia cell line by all-trans-retinoic acid (ATRA) treatment. Here, we report that the H3K9 methyltransferase G9a negatively regulated JAK2 transcription in histone methyltransferase activity and in a YY1-dependent manner during ATRA-mediated leukemia cell differentiation. We found that G9a knockdown repressed ATRA-mediated HL-60 cell differentiation. We demonstrated that G9a interacts with YY1 and is recruited to the JAK2 promoter along with corepressors, including histone deacetylase, that induced H3K9-me2. Repression of JAK2 transcription by G9a decreased H3Y41 phosphorylation and promoted inhibition of the recently identified JAK2-H3Y41P-HP1α pathway-mediated leukemogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Cell Differentiation / drug effects
  • Chromobox Protein Homolog 5
  • Gene Expression Regulation, Neoplastic
  • HL-60 Cells
  • Histocompatibility Antigens / genetics
  • Histocompatibility Antigens / metabolism*
  • Histone-Lysine N-Methyltransferase / genetics
  • Histone-Lysine N-Methyltransferase / metabolism*
  • Humans
  • Janus Kinase 2 / biosynthesis
  • Janus Kinase 2 / metabolism*
  • K562 Cells
  • LIM Domain Proteins / genetics
  • Leukemia / metabolism*
  • Leukemia / pathology
  • Methylation
  • Phosphorylation
  • Promoter Regions, Genetic
  • Proto-Oncogene Proteins / genetics
  • Transcription, Genetic
  • Tretinoin / pharmacology
  • YY1 Transcription Factor / metabolism*

Substances

  • Adaptor Proteins, Signal Transducing
  • CBX5 protein, human
  • Histocompatibility Antigens
  • LIM Domain Proteins
  • LMO2 protein, human
  • Proto-Oncogene Proteins
  • YY1 Transcription Factor
  • YY1 protein, human
  • Chromobox Protein Homolog 5
  • Tretinoin
  • EHMT2 protein, human
  • Histone-Lysine N-Methyltransferase
  • JAK2 protein, human
  • Janus Kinase 2