Shao Qun, Liu Xiaofan, Su Tong, Ma Changle, Wang Pingping
Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan, China.
Front Plant Sci. 2019 Dec 10;10:1568. doi: 10.3389/fpls.2019.01568. eCollection 2019.
Oil bodies (OBs) are ubiquitous dynamic organelles found in plant seeds. They have attracted increasing attention recently because of their important roles in plant physiology. First, the neutral lipids stored within these organelles serve as an initial, essential source of energy and carbon for seed germination and post-germinative growth of the seedlings. Secondly, they are involved in many other cellular processes such as stress responses, lipid metabolism, organ development, and hormone signaling. The biological functions of seed OBs are dependent on structural proteins, principally oleosins, caleosins, and steroleosins, which are embedded in the OB phospholipid monolayer. Oleosin and caleosin proteins are specific to plants and mainly act as OB structural proteins and are important for the biogenesis, stability, and dynamics of the organelle; whereas steroleosin proteins are also present in mammals and play an important role in steroid hormone metabolism and signaling. Significant progress using new genetic, biochemical, and imaging technologies has uncovered the roles of these proteins. Here, we review recent work on the structural or metabolic roles of these proteins in OB biogenesis, stabilization and degradation, lipid homeostasis and mobilization, hormone signal transduction, stress defenses, and various aspects of plant growth and development.
油体（OBs）是植物种子中普遍存在的动态细胞器。由于它们在植物生理学中发挥的重要作用，近年来受到了越来越多的关注。首先，这些细胞器中储存的中性脂质是种子萌发和幼苗萌发后生长的初始必需能量和碳源。其次，它们参与许多其他细胞过程，如应激反应、脂质代谢、器官发育和激素信号传导。种子油体的生物学功能依赖于结构蛋白，主要是油质蛋白、钙结合油质蛋白和固醇油质蛋白，它们嵌入油体磷脂单层中。油质蛋白和钙结合油质蛋白是植物特有的，主要作为油体结构蛋白，对细胞器的生物发生、稳定性和动态变化很重要；而固醇油质蛋白也存在于哺乳动物中，在类固醇激素代谢和信号传导中起重要作用。利用新的遗传、生化和成像技术取得的重大进展揭示了这些蛋白质的作用。在这里，我们综述了这些蛋白质在油体生物发生、稳定和降解、脂质稳态和动员、激素信号转导、应激防御以及植物生长发育各个方面的结构或代谢作用的最新研究成果。
