Analysis on the mechanism of ER membrane proliferation upon ER protein overproduction in yeast

酵母内质网蛋白过量产生内质网膜增殖机制分析

• 批准号: 10460034
• 负责人: OHTA Akinori
• 金额: $ 8.45万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10460034/
• 关键词: endoplasmic reticulum; Saccharomyces cerevisiae; Candida maltosa; cytochrome P450A1k; ER proliferation; phospholipid; IRE1; ER membrane; cytochrome P45Alk

Endoplasmic reticulum (ER) is the center of secretory protein and lipid syntheses in eukaryotic cells. Although it has been attracted many researchers who are interested in those biosynthetic pathways, its proliferation and biogenesis are not yet well understood. We overproduced an ER membrane protein cytochrome P450Alk1 of Candida maltosa in Saccharomyces cerevisiae and analyzed the mechanism of the resultant ER proliferation, especially in the aspects of ER chaperone induction and membrane lipid metabolism. The results are; 1) There is no enhanced synthesis of membrane phospholipids during ER proliferation. 2) The requirement of Ire1p for ER proliferation is dependent on the genetic backgrounds of employed yeast strains. 3) Degradation of ER misfolded proteins does not necessarily occur by the proteasome system. 4) We established a system where yeast growth is dependent on the externally-supplied phospholipids. This enables us to analyze membrane lipid metabolism during ER protein-induced ER proliferation.

内质网（ER）是真核细胞分泌蛋白质和脂质合成的中心。尽管它吸引了许多对这些生物合成途径感兴趣的研究人员，但其增殖和生物发生尚不清楚。我们在酿酒酵母中过量产生了麦芽糖念珠菌的内质网膜蛋白细胞色素P450Alk1，并分析了所得内质网增殖的机制，特别是在内质网伴侣诱导和膜脂代谢方面。结果是； 1) ER增殖过程中膜磷脂的合成没有增强。 2) Ire1p 对 ER 增殖的要求取决于所用酵母菌株的遗传背景。 3) ER错误折叠蛋白的降解不一定由蛋白酶体系统发生。 4）我们建立了一个系统，其中酵母生长依赖于外部提供的磷脂。这使我们能够分析 ER 蛋白诱导的 ER 增殖过程中的膜脂代谢。

项目成果

Umebayasi,K.,Hirata,A.,et al.: "Unfolded protein response-induced BiP/Kar2p production protects cell growth against accumulation of misfolded protein aggregates in the yeast endoplasmic reticulum"European Journal of Cell Biology. 78. 726-738 (1999)

Umebayasi,K.,Hirata,A.,et al.：“未折叠蛋白质反应诱导的 BiP/Kar2p 产生可保护细胞生长，防止酵母内质网中错误折叠蛋白质聚集体的积累”《欧洲细胞生物学杂志》。

Nakamura,H.,Miura,K.,et al.: "Phosphatidylserine synthesis required for the maximal tryptophan transport activity in Saccharomyces cerevisiae"Bioscience,Biotechnology,and Biochemistry. 64. 167-172 (2000)

Nakamura, H., Miura, K., et al.：“酿酒酵母中最大色氨酸转运活性所需的磷脂酰丝氨酸合成”生物科学、生物技术和生物化学。

Umebayasi,K.,Hirata,A., et al.: "Unfolded protein response-induced BiP/Kar2p production protects cell growth against accumu protein aggregates in the yeast endoplasmic reticulum."European Journal of Cell Biology. 78. 726-738 (1999)

Umebayasi,K.、Hirata,A. 等人：“未折叠的蛋白质反应诱导的 BiP/Kar2p 产生可保护细胞生长免受酵母内质网中accummu 蛋白质聚集的影响。”《欧洲细胞生物学杂志》。

Takewaka,T.,Zimmer,T., et al.: "Null mutation in IRE1 gene inhibits Overproduction of microsome P450Alk1 (CYP52A3) and endoplasmic reticulum in Saccharomyces cerevisiae"Journal of Biochemistry. 125. 507-514 (1999)

Takewaka,T.,Zimmer,T.等人：“IRE1 基因的无效突变抑制酿酒酵母中微粒体 P450Alk1 (CYP52A3) 和内质网的过量生产”《生物化学杂志》。

Yon,J-O,Nakamura,H.et al.: "Incorporation of extracellular phospholipids and their effect on the growth and lipid metabolism of the Saccharomyces cerevisiae cho1/pss mutant"Biochimica Biophysica et Acta. 1394. 23-32 (1998)

Yon,J-O,Nakamura,H.et al.：“细胞外磷脂的掺入及其对酿酒酵母 cho1/pss 突变体的生长和脂质代谢的影响”Biochimica Biophysicala et Acta。