Department of Biology, University of Missouri-St. Louis, St. Louis, MO 63121 and Donald Danforth Plant Science Center, St. Louis, MO 63132, U.S.A.
Essays Biochem. 2020 Sep 23;64(3):533-546. doi: 10.1042/EBC20190089.
Lipids function not only as the major structural components of cell membranes, but also as molecular messengers that transduce signals to trigger downstream signaling events in the cell. Phosphatidic acid (PA), the simplest and a minor class of glycerophospholipids, is a key intermediate for the synthesis of membrane and storage lipids, and also plays important roles in mediating diverse cellular and physiological processes in eukaryotes ranging from microbes to mammals and higher plants. PA comprises different molecular species that can act differently, and is found in virtually all organisms, tissues, and organellar membranes, with variations in total content and molecular species composition. The cellular levels of PA are highly dynamic in response to stimuli and multiple enzymatic reactions can mediate its production and degradation. Moreover, its unique physicochemical properties compared with other glycerophospholipids allow PA to influence membrane structure and dynamics, and interact with various proteins. PA has emerged as a class of new lipid mediators modulating various signaling and cellular processes via its versatile effects, such as membrane tethering, conformational changes, and enzymatic activities of target proteins, and vesicular trafficking.
脂质不仅作为细胞膜的主要结构成分，还作为分子信使，将信号转导到细胞内引发下游信号事件。磷脂酸 (PA) 是最简单和少量的甘油磷脂之一，是合成膜和储存脂质的关键中间产物，在真核生物（从微生物到哺乳动物和高等植物）中调节多种细胞和生理过程中也发挥着重要作用。PA 包含不同的分子种类，它们的作用可能不同，几乎存在于所有生物体、组织和细胞器膜中，其总含量和分子种类组成存在差异。PA 的细胞水平对刺激具有高度动态性，多种酶促反应可以介导其产生和降解。此外，与其他甘油磷脂相比，其独特的物理化学性质允许 PA 影响膜结构和动力学，并与各种蛋白质相互作用。PA 已成为一类新型脂质介质，通过其多种作用（如膜连接、构象变化和靶蛋白的酶活性以及囊泡运输）来调节各种信号和细胞过程。
