Sumoylation is critical for DJ-1 to repress p53 transcriptional activity.

Sumoylation is an important post-translational modification, which is also involved in the pathogenesis of many neurodegenerative diseases. We previously reported that DJ-1 decreases Bcl-2 associated X protein expression through repressing p53 transcriptional activity. Here we show that DJ-1(K130R), the non-sumoylatable mutant form of DJ-1, shifts from nucleus to cytoplasm, fails to repress p53 transcriptional activity and loses its protective function against ultraviolet induced cell death. Our findings suggest that sumoylation is critical for DJ-1 to repress p53 transcriptional activity.