Human ribosomal protein S3 (rpS3) acts as a DNA repair endonuclease. The multiple functions of this protein are regulated by post-translational modifications including phosphorylation and methylation. Using a yeast-two hybrid screen, we identified small ubiquitin-related modifier-1 (SUMO-1) as a new interacting partner of rpS3. rpS3 interacted with SUMO-1 via the N- and C-terminal regions. We also observed sumoylation of rpS3 in Escherichia coli and mammalian cell systems. Furthermore, we discovered that one of three lysine residues, Lys18, Lys214, or Lys230, was sumoylated in rpS3. Interestingly, sumoylated rpS3 was resistant to proteolytic activity, indicating that SUMO-1 increased the stability of the rpS3 protein. We concluded that rpS3 is covalently modified by SUMO-1 and this post-translational modification regulates rpS3 function by increasing rpS3 protein stability.
|Number of pages||5|
|Journal||Biochemical and biophysical research communications|
|Publication status||Published - 2011 Oct 28|
Bibliographical noteFunding Information:
This work is supported in part by grants from National Research Foundation of Korea (FRP08B1-230, KRF-2009-0086319, 2011-0019059, and 2011-0030700). We give thanks to Dr. Ahn of Sungkyunkwan University, Korea for the technical assistance for Aos1-Uba2 fusion protein expression.
- Protein stability
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology