Ubiquitin-dependent 26S proteasomal pathway: a role in the degradation of native human liver CYP3A4 expressed in Saccharomyces cerevisiae?
Ubiquitin-dependent 26S proteasomal pathway: a role in the degradation of native human liver CYP3A4 expressed in Saccharomyces cerevisiae?
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泛素依赖性 26S 蛋白酶体途径：在酿酒酵母中表达的天然人肝脏 CYP3A4 降解中的作用？
DOI：
10.1006/abbi.2001.2482
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发表时间：
2001
影响因子：
3.9
通讯作者：
Correia,MA
中科院分区：
文献类型：
--
作者：
Murray,BP;Correia,MA
细胞色素P450（CYP3A4）是人类肝脏内质网（ER）中主要的血红素蛋白酶，负责超过60%的临床相关药物的代谢。我们先前已经表明，通过血红素修饰其蛋白质部分，CYP 3A4及其大鼠肝ER直向同源物CYP 3A的基于机制的自杀失活导致其泛素（Ub）依赖性26S蛋白酶体降解（Korsmeyer等人（1999）Arch.Biochem.Biophys.2004，2005）。365，31; Wang等人（1999）Arch.Biochem.Biophys. 365，45）。这并不奇怪，因为血红素修饰的CYP3A蛋白质在结构上受损。为了确定天然酶的周转是否类似地募集该途径，我们在野生型酿酒酵母和突变株中异源表达该蛋白（hrd1 Δ、hrd2 - 1和hrd3 Δ）先前显示在多位ER蛋白3-羟基-3-甲基戊二酰-CoA还原酶的Ub依赖性26 S蛋白酶体降解中存在缺陷（同种型Hmg 2p），甾醇生物合成中的限速酶，以及ER相关的Ub-缀合酶Ubc 6 p和/或Ubc 7 p缺陷的菌株（汉普顿等人（1996）Mol. Cell 7，2029;汉普顿和巴克塔（Bhakta）（1997）美国国家科学院院刊（Proc.Natl. Acad. sci. USA 94，12，944）。我们的研究结果表明，在共同的Hmg2p的降解，天然CYP3A4也需要Hrd2p（26 S蛋白酶体的19S帽复合物的亚基）和Ubc7p，并在较小程度上Hrd3p，ER相关的Ub连接酶复合物的一个组成部分。与Hmg2p降解相反，天然CYP3A4的降解似乎并不绝对需要ER相关Ub连接酶复合物的另一种组分Hrd1p。此外，在S.酿酒酵母pep4 Δ菌株被证明在羧肽酶Y的液泡降解中存在缺陷，表明CYP3A4的降解在很大程度上也不依赖于液泡（溶酶体）蛋白水解功能。另外两个天然ER蛋白，Sec61p和Sec63p，ER易位子的正常成分的降解，也进行了平行检查，并发现在一定程度上稳定在HRD 2和UBC 7缺陷株。这些发现共同证明了ER蛋白正常降解的显著机制多样性。
Cytochrome P450, CYP3A4, is the dominant human liver endoplasmic reticulum (ER) hemoprotein enzyme, responsible for the metabolism of over 60% of clinically relevant drugs. We have previously shown that mechanism-based suicide inactivation of CYP3A4 and its rat liver ER orthologs, CYPs 3A, via heme-modification of their protein moieties, results in their ubiquitin (Ub)-dependent 26S proteasomal degradation (Korsmeyer et al. (1999) Arch. Biochem. Biophys. 365, 31; Wang et al. (1999) Arch. Biochem. Biophys. 365, 45). This is not surprising given that the heme-modified CYP3A proteins are structurally damaged. To determine whether the turnover of the native enzyme similarly recruited this pathway, we heterologously expressed this protein in wild-type Saccharomyces cerevisiae and mutant strains (hrd1Δ, hrd2-1, and hrd3Δ) previously shown to be deficient in the Ub-dependent 26S proteasomal degradation of the polytopic ER protein 3-hydroxy-3-methylglutaryl-CoA reductase (isoform Hmg2p), the rate-limiting enzyme in sterol biosynthesis, as well as in strains deficient in ER-associated Ub-conjugating enzymes, Ubc6p and/or Ubc7p (Hampton et al. (1996) Mol. Biol. Cell 7, 2029; Hampton and Bhakta (1997) Proc. Natl. Acad. Sci. USA 94, 12,944). Our findings reveal that in common with the degradation of Hmg2p, that of native CYP3A4 also requires Hrd2p (a subunit of the 19S cap complex of the 26S proteasome) and Ubc7p, and to a much lesser extent Hrd3p, a component of the ER-associated Ub-ligase complex. In contrast to Hmg2p-degradation, that of native CYP3A4 does not appear to absolutely require Hrd1p, another component of the ER-associated Ub–ligase complex. Furthermore, studies in a S. cerevisiae pep4Δ strain proven to be deficient in the vacuolar degradation of carboxypeptidase Y indicated that CYP3A4 degradation is also largely independent of vacuolar (lysosomal) proteolytic function. The degradation of two other native ER proteins, Sec61p and Sec63p, normal components of the ER translocon, were also examined in parallel and found to be stabilized to some extent in HRD2- and UBC7-deficient strains. Together these findings attest to the remarkable mechanistic diversity in the normal degradation of ER proteins.
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丙酮调节大鼠肝脏细胞色素 P4502E2 和细胞色素 P4502B1 的合成和降解
DOI：
--
发表时间：
1991
期刊：
影响因子：
--
作者：
M. Ronis;I. Johansson;K. Hultenby;J. Lagercrantz;H. Glaumann;M. Ingelman
通讯作者：
M. Ingelman
在 3,5-二乙氧基羰基-1,4-二氢-2,4,6-三甲基吡啶的 4-烷基类似物灭活细胞色素 P450 过程中，血红素与微粒体蛋白不可逆结合。
影响因子：
5.8
作者：
D. S. Riddick;G. S. Marks
通讯作者：
G. S. Marks
细胞色素 P450 周转。
影响因子：
--
作者：
Correia,MA
通讯作者：
Correia,MA
影响因子：
--
作者：
G. Pfeifer;A. Riggs
通讯作者：
G. Pfeifer;A. Riggs
离体大鼠肝细胞中细胞色素 P450 3A 的降解：26S 蛋白酶体抑制剂作为探针。
影响因子：
3.9
作者：
Wang,HF;FigueiredoPereira,ME;Correia,MA
通讯作者：
Correia,MA