Wang Yicheng, Kinoshita Taroh
State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
Key Laboratory of Biopharmaceutical Preparation and Delivery, Chinese Academy of Sciences, Beijing 100190, China.
Biochem Soc Trans. 2023 Oct 31;51(5):1857-1869. doi: 10.1042/BST20221455.
Glycerophospholipids, sphingolipids and cholesterol assemble into lipid bilayers that form the scaffold of cellular membranes, in which proteins are embedded. Membrane composition and membrane protein profiles differ between plasma and intracellular membranes and between the two leaflets of a membrane. Lipid distributions between two leaflets are mediated by lipid translocases, including flippases and scramblases. Flippases use ATP to catalyze the inward movement of specific lipids between leaflets. In contrast, bidirectional flip-flop movements of lipids across the membrane are mediated by scramblases in an ATP-independent manner. Scramblases have been implicated in disrupting the lipid asymmetry of the plasma membrane, protein glycosylation, autophagosome biogenesis, lipoprotein secretion, lipid droplet formation and communications between organelles. Although scramblases in plasma membranes were identified over 10 years ago, most progress about scramblases localized in intracellular membranes has been made in the last few years. Herein, we review the role of scramblases in regulating lipid distributions in cellular membranes, focusing primarily on intracellular membrane-localized scramblases.
甘油磷脂、鞘脂和胆固醇组装成脂质双层，形成细胞膜的支架，蛋白质嵌入其中。质膜和细胞内膜之间以及膜的两个小叶之间的膜组成和膜蛋白谱有所不同。两个小叶之间的脂质分布由脂质转位酶介导，包括翻转酶和翻转酶。翻转酶利用ATP催化特定脂质在小叶之间向内移动。相比之下，脂质跨膜的双向翻转运动由翻转酶以不依赖ATP的方式介导。翻转酶与破坏质膜的脂质不对称性、蛋白质糖基化、自噬体生物发生、脂蛋白分泌、脂滴形成以及细胞器之间的通讯有关。尽管质膜中的翻转酶在10多年前就已被鉴定出来，但关于定位在细胞内膜中的翻转酶的大多数进展是在过去几年中取得的。在此，我们综述了翻转酶在调节细胞膜脂质分布中的作用，主要关注定位在细胞内膜中的翻转酶。
