| First Author | Pickering AM | Year | 2012 |
| Journal | Arch Biochem Biophys | Volume | 523 |
| Issue | 2 | Pages | 181-90 |
| PubMed ID | 22564544 | Mgi Jnum | J:196813 |
| Mgi Id | MGI:5489974 | Doi | 10.1016/j.abb.2012.04.018 |
| Citation | Pickering AM, et al. (2012) Differential roles of proteasome and immunoproteasome regulators Pa28alphabeta, Pa28gamma and Pa200 in the degradation of oxidized proteins. Arch Biochem Biophys 523(2):181-90 |
| abstractText | The response and functions of proteasome regulators Pa28alphabeta (or 11S), Pa28gamma and Pa200 in oxidative-stress adaptation (also called hormesis) was studied in murine embryonic fibroblasts (MEFs), using a well-characterized model of cellular adaptation to low concentrations (1.0-10.0 muM) of hydrogen peroxide (H(2)O(2)), which alter gene expression profiles, increasing resistance to higher levels of oxidative-stress. Pa28alphabeta bound to 20S proteasomes immediately upon H(2)O(2)-treatment, whereas 26S proteasomes were disassembled at the same time. Over the next 24h, the levels of Pa28alphabeta, Pa28gamma and Pa200 proteasome regulators increased during H(2)O(2)-adaptation, whereas the 19S regulator was unchanged. Purified Pa28alphabeta, and to a lesser extent Pa28gamma, significantly increased the ability of purified 20S proteasome to selectively degrade oxidized proteins; Pa28alphabeta also increased the capacity of purified immunoproteasome to selectively degrade oxidized proteins but Pa28gamma did not. Pa200 regulator actually decreased 20S proteasome and immunoproteasome's ability to degrade oxidized proteins but Pa200 and poly-ADP ribose polymerase may cooperate in enabling initiation of DNA repair. Our results indicate that cytoplasmic Pa28alphabeta and nuclear Pa28gamma may both be important regulators of proteasome's ability to degrade oxidatively-damaged proteins, and induced-expression of both 20S proteasome and immunoproteasome, and their Pa28alphabeta and Pa28gamma regulators are important for oxidative-stress adaptation. |
