Phosphorylation of the oncogenic transcription factor ERG in prostate cells dissociates polycomb repressive complex 2, allowing target gene activation

Vivekananda Kedage, Brady G. Strittmatter, Paige B. Dausinas, Peter C. Hollenhorst

Research output: Contribution to journalArticle

5 Scopus citations


In ∼50% of prostate cancers, chromosomal rearrangements cause the fusion of the promoter and 5′-UTR of the androgenregulated TMPRSS2 (transmembrane protease, serine 2) gene to the open reading frame of ERG, encoding an ETS family transcription factor. This fusion results in expression of full-length or N-terminally truncated ERG protein in prostate epithelia. ERG is not expressed in normal prostate epithelia, but when expressed, it promotes tumorigenesis via altered gene expression, stimulating epithelial-mesenchymal transition, cellular migration/invasion, and transformation. However, limited knowledge about the molecular mechanisms of ERG function in prostate cells has hampered efforts to therapeutically target ERG. ERK-mediated phosphorylation of ERG is required for ERG functions in prostate cells, but the reason for this requirement is unknown. Here, we report a mechanism whereby ERKmediated phosphorylation of ERG at one serine residue causes a conformational change that allows ERK phosphorylation at a second serine residue, Ser-96. We found that the Ser-96 phosphorylation resulted in dissociation of EZH2 and SUZ12, components of polycomb repressive complex 2 (PRC2), transcriptional activation of ERG target genes, and increased cell migration. Conversely, loss of ERG phosphorylation at Ser-96 resulted in recruitment of EZH2 across the ERG-cistrome and a genome-wide loss of ERG-mediated transcriptional activation and cell migration. In conclusion, our findings have identified critical molecular mechanisms involving ERK-mediated ERG activation that could be exploited for therapeutic intervention in ERG-positive prostate cancers.

Original languageEnglish (US)
Pages (from-to)17225-17235
Number of pages11
JournalJournal of Biological Chemistry
Issue number42
StatePublished - Oct 20 2017


ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

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