Proteasomal degradation of retinoblastoma-related p130 during adipocyte differentiation.
Proteasomal degradation of retinoblastoma-related p130 during adipocyte differentiation.
复制标题
脂肪细胞分化过程中视网膜母细胞瘤相关 p130 的蛋白酶体降解。
DOI：
10.1006/bbrc.2001.6291
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
McGeheeJr,RobertE
中科院分区：
文献类型：
--
作者：
Prince,AudraM;May,JulieS;Burton,GregoryR;Lyle,RobertE;McGeheeJr,RobertE
Within 24 h of hormonally stimulated 3T3-L1 adipocyte differentiation, there are dramatic changes in the protein levels of p130 and p107, two members of the retinoblastoma tumor suppressor gene family. Designated the “p103:p107” switch, this alteration is characterized by a rapid and transient drop in p130 protein levels accompanied by a transient increase in both p107 mRNA and protein levels. Using protease inhibitors, the specific proteolytic pathway involved in degradation of p130 was examined. Treatment of cells with N-acetyl-leu-leu-norleucinal, an inhibitor that blocks proteolytic activity of type I calpain and the 26S proteasome, resulted in a complete block in the degradation of p130 protein, as well as adipocyte differentiation, suggesting that one of these pathways is involved in regulating p130 protein levels. Similar analysis with lactacystin, a specific inhibitor of the 26S proteasome, also resulted in a complete block in both differentiation and p130 degradation. Furthermore, both inhibitors blocked the increase in p107 protein levels normally observed on Day 1, suggesting that the p130:p107 switch is required for adipocyte differentiation and one of the early molecular events involved in activating the p130:p107 switch is the specific degradation of p130 by the 26S proteasome.
