Functional proteomics of the epigenetic regulators ASXL1, ASXL2 and ASXL3: a convergence of proteomics and epigenetics for translational medicine

Expert Rev Proteomics. 2015 Jun;12(3):317-28. doi: 10.1586/14789450.2015.1033409. Epub 2015 Apr 3.


ASXL1, ASXL2 and ASXL3 are epigenetic scaffolds for BAP1, EZH2, NCOA1, nuclear receptors and WTIP. Here, functional proteomics of the ASXL family members are reviewed with emphasis on mutation spectra, the ASXM2 domain and the plant homeodomain (PHD) finger. Copy number gains of ASXL1 occur in chromosome 20q11.2 duplication syndrome and cervical cancer. Truncation mutations of ASXLs occur in autism, Bohring-Opitz and related syndromes, hematological malignancies and solid tumors, such as prostate cancer, breast cancer and high-grade glioma, which are gain- or loss-of-function mutations. The ASXM2 domain is a binding module for androgen receptor and estrogen receptor α, while the PHD finger is a ligand of WTIP LIM domains and a putative chromatin-binding module. Phylogenetic analyses of 139 human PHD fingers revealed that ASXL PHD fingers cluster with those of BPTF, DIDO, ING1, KDM5A (JARID1A), KMT2E (MLL5), PHF2, PHF8 and PHF23. The cell context-dependent epigenetic code of ASXLs should be deciphered to develop therapeutics for human diseases.

Keywords: Forkhead-box transcription factor; acute myeloid leukemia; cardiovascular development; colorectal cancer; hepatocellular carcinoma; melanoma; microsatellite instability; myelodysplastic syndrome; ovarian cancer; pancreatic cancer.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Epigenesis, Genetic*
  • Humans
  • Mutation
  • Protein Structure, Tertiary / genetics
  • Proteomics*
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Translational Research, Biomedical*


  • ASXL1 protein, human
  • ASXL2 protein, human
  • ASXL3 protein, human
  • Repressor Proteins
  • Transcription Factors