Proteome-wide Mapping of Endogenous SUMOylation Sites in Mouse Testis

Mol Cell Proteomics. 2017 May;16(5):717-727. doi: 10.1074/mcp.M116.062125. Epub 2017 Mar 13.

Abstract

SUMOylation is a reversible post-translational modification involved in various critical biological processes. To date, there is limited approach for endogenous wild-type SUMO-modified peptides enrichment and SUMOylation sites identification. In this study, we generated a high-affinity SUMO1 antibody to facilitate the enrichment of endogenous SUMO1-modified peptides from Trypsin/Lys-C protease digestion. Following secondary Glu-C protease digestion, we identified 53 high-confidence SUMO1-modified sites from mouse testis by using high-resolution mass spectrometry. Bioinformatics analyses showed that SUMO1-modified proteins were enriched in transcription regulation and DNA repair. Nab1 was validated to be an authentic SUMOylated protein and Lys479 was identified to be the major SUMOylation site. The SUMOylation of Nab1 enhanced its interaction with HDAC2 and maintained its inhibitory effect on EGR1 transcriptional activity. Therefore, we provided a novel approach to investigating endogenous SUMOylation sites in tissue samples.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies / metabolism
  • Computational Biology
  • HEK293 Cells
  • Humans
  • Male
  • Mass Spectrometry
  • Mice, Inbred C57BL
  • Peptides / metabolism
  • Protein Processing, Post-Translational
  • Proteome / metabolism*
  • Reproducibility of Results
  • SUMO-1 Protein / chemistry
  • SUMO-1 Protein / metabolism
  • Sumoylation*
  • Testis / metabolism*
  • Transcription, Genetic

Substances

  • Antibodies
  • Peptides
  • Proteome
  • SUMO-1 Protein