Fang M, Kearns B G, Gedvilaite A, Kagiwada S, Kearns M, Fung M K, Bankaitis V A
Department of Cell Biology, University of Alabama at Birmingham, 35294-0005, USA.
EMBO J. 1996 Dec 2;15(23):6447-59.
The yeast phosphatidylinositol transfer protein (Sec14p) is required for biogenesis of Golgi-derived transport vesicles and cell viability, and this essential Sec14p requirement is abrogated by inactivation of the CDP-choline pathway for phosphatidylcholine biosynthesis. These findings indicate that Sec14p functions to alleviate a CDP-choline pathway-mediated toxicity to yeast Golgi secretory function. We now report that this toxicity is manifested through the action of yeast Kes1p, a polypeptide that shares homology with the ligand-binding domain of human oxysterol binding protein (OSBP). Identification of Kes1p as a negative effector for Golgi function provides the first direct insight into the biological role of any member of the OSBP family, and describes a novel pathway for the regulation of Golgi-derived transport vesicle biogenesis.
酵母磷脂酰肌醇转移蛋白（Sec14p）是高尔基体衍生运输小泡生物合成和细胞活力所必需的，而磷脂酰胆碱生物合成的CDP-胆碱途径失活可消除对这种必需的Sec14p的需求。这些发现表明，Sec14p的功能是减轻CDP-胆碱途径介导的对酵母高尔基体分泌功能的毒性。我们现在报告，这种毒性是通过酵母Kes1p的作用表现出来的，Kes1p是一种与人类氧化甾醇结合蛋白（OSBP）的配体结合域具有同源性的多肽。将Kes1p鉴定为高尔基体功能的负效应物，首次直接深入了解了OSBP家族任何成员的生物学作用，并描述了一种调节高尔基体衍生运输小泡生物合成的新途径。
