Biochemistry and Physiology of Plants, Faculty of Biology, Bielefeld University, Bielefeld, Germany.
Int Rev Cell Mol Biol. 2013;304:57-131. doi: 10.1016/B978-0-12-407696-9.00002-6.
The plant vacuole is of prime importance in buffering environmental perturbations and in coping with abiotic stress caused by, for example, drought, salinity, cold, or UV. The large volume, the efficient integration in anterograde and retrograde vesicular trafficking, and the dynamic equipment with tonoplast transporters enable the vacuole to fulfill indispensible functions in cell biology, for example, transient and permanent storage, detoxification, recycling, pH and redox homeostasis, cell expansion, biotic defence, and cell death. This review first focuses on endomembrane dynamics and then summarizes the functions, assembly, and regulation of secretory and vacuolar proton pumps: (i) the vacuolar H(+)-ATPase (V-ATPase) which represents a multimeric complex of approximately 800 kDa, (ii) the vacuolar H(+)-pyrophosphatase, and (iii) the plasma membrane H(+)-ATPase. These primary proton pumps regulate the cytosolic pH and provide the driving force for secondary active transport. Carriers and ion channels modulate the proton motif force and catalyze uptake and vacuolar compartmentation of solutes and deposition of xenobiotics or secondary compounds such as flavonoids. ABC-type transporters directly energized by MgATP complement the transport portfolio that realizes the multiple functions in stress tolerance of plants.
植物液泡在缓冲环境胁迫和应对非生物胁迫方面至关重要,例如干旱、盐度、寒冷或 UV 等因素引起的胁迫。液泡的大体积、在顺行和逆行小泡运输中的有效整合以及动态的液泡膜转运蛋白设备,使液泡能够在细胞生物学中发挥不可或缺的功能,例如短暂和永久储存、解毒、回收、pH 值和氧化还原平衡、细胞扩张、生物防御和细胞死亡。这篇综述首先关注内膜动力学,然后总结了分泌和液泡质子泵的功能、组装和调节:(i) 液泡 H(+)-ATP 酶 (V-ATPase),它是一个约 800 kDa 的多聚体复合物,(ii) 液泡 H(+)-焦磷酸酶,和 (iii) 质膜 H(+)-ATP 酶。这些初级质子泵调节细胞质 pH 值,并为次级主动运输提供驱动力。载体和离子通道调节质子动力,并催化溶质的摄取和液泡区室化以及异生素或黄酮类等次级化合物的沉积。由 MgATP 直接供能的 ABC 型转运蛋白补充了实现植物耐胁迫多种功能的运输组合。