Abstract

PURPOSE
Proteolysis is an important way to regulate cell cycle regulatory proteins. Ubiquitin- proteasome pathway regards as highly selective proteolytic machinary mostly in physiological state. We investigated the role of ubiquitin-proteasome pathway in p107 protein degradation.
MATERIALS AND METHODS
p107 protein level was determined by western blot analysis in Ewings sarcoma cell line incubated with HMG-CoA inhibitor lovastatin. Recovery of p107 protein was determined with inhibitors of proteasome, serine protease or caspase. Ubiquitination of p107 protein was assessed by ubiquitin western analysis.
RESULTS
pl07 protein level was decreased with lovastin and its proteolytic effect was counteracted with proteasome inhibitors. Ubiquitin western analysis showed p107 protein fragments were tagged with ubiquitin and it was more evident with specific proteasome inhibitor lactacystin.
CONCLUSION
Lovastatin drives p107 protein to be degraded. In a certain circumstance proteolysis of p107 protein was executed by ubiquitin-proteasome pathway.

• Keywords: p107 protein;Proteolysis;Ubiquitin-proteasome pathway