Department of Botany and Center for Quantitative Cell Imaging, University of Wisconsin-Madison, WI, USA.
FEBS Lett. 2022 Sep;596(17):2288-2304. doi: 10.1002/1873-3468.14425. Epub 2022 Jun 17.
Endocytosis, secretion, and endosomal trafficking are key cellular processes that control the composition of the plasma membrane. Through the coordination of these trafficking pathways, cells can adjust the composition, localization, and turnover of proteins and lipids in response to developmental or environmental cues. Upon being incorporated into vesicles and internalized through endocytosis, plant plasma membrane proteins are delivered to the trans-Golgi network (TGN). At the TGN, plasma membrane proteins are recycled back to the plasma membrane or transferred to multivesicular endosomes (MVEs), where they are further sorted into intralumenal vesicles for degradation in the vacuole. Both types of plant endosomes, TGN and MVEs, act as sorting organelles for multiple endocytic, recycling, and secretory pathways. Molecular assemblies such as retromer, ESCRT (endosomal sorting complex required for transport) machinery, small GTPases, adaptor proteins, and SNAREs associate with specific domains of endosomal membranes to mediate different sorting and membrane-budding events. In this review, we discuss the mechanisms underlying the recognition and sorting of proteins at endosomes, membrane remodeling and budding, and their implications for cellular trafficking and physiological responses in plants.
内吞作用、分泌作用和内体运输是控制质膜组成的关键细胞过程。通过这些运输途径的协调，细胞可以响应发育或环境信号来调节蛋白质和脂质的组成、定位和周转率。植物质膜蛋白在被包裹在囊泡内并通过内吞作用内化后，被递送到高尔基网络 (TGN)。在 TGN 中，质膜蛋白被回收回质膜或被转移到多泡体 (MVEs)，在那里它们进一步分拣到腔内囊泡中，在液泡中降解。TGN 和 MVEs 这两种植物内体都充当多种内吞作用、回收和分泌途径的分选细胞器。分子组装体，如逆行蛋白(retromer)、内体分选复合物需要运输的 ESCRT 机器、小 GTPases、衔接蛋白和 SNAREs，与内体膜的特定结构域结合，介导不同的分选和膜出芽事件。在这篇综述中，我们讨论了内体中蛋白质的识别和分选、膜重塑和出芽的机制，以及它们对植物细胞运输和生理反应的影响。
