pH in the plant endomembrane system-an import and export business.
pH in the plant endomembrane system-an import and export business.
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DOI：
10.1016/j.pbi.2014.09.005
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发表时间：
2014-12
影响因子：
9.5
通讯作者：
K. Schumacher
中科院分区：
文献类型：
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作者：
K. Schumacher
亮点缺乏液泡膜 V-ATPase 或 V-PPase 的突变体有助于揭示两种主要质子泵对液泡酸化的相对贡献。矮牵牛花瓣表皮细胞中的液泡酸化是由两种 P 型 H+-ATPase (P3A+ P3B) 组成的异二聚体介导的。NHX 转运蛋白的 K+/H+ 交换对于液泡钾积累和 pH 非常重要体内平衡。基因编码的传感器允许对内膜系统不同区室的体内 pH 值进行测量。pH 体内平衡是所有植物细胞中的一个重要过程，维持内膜系统区室中正确的腔内 pH 值不仅对于二次主动运输很重要，而且对于包括蛋白质修饰、分类和运输在内的各种细胞功能也很重要。由于其生电性，主 H+ 泵无法单独建立和控制通常较大的质子梯度，而是需要其他离子转运蛋白的共同作用，这些离子转运蛋白可充当分流电导或质子泄漏。因此，在这里，我将重点关注最近的结果，这些结果强调了质子泵和质子耦合转运蛋白在控制植物内膜系统区室 pH 值方面的相互作用。
HighlightsMutants lacking either tonoplast V-ATPase or V-PPase help to reveal the relative contributions to vacuolar acidification by the two major proton-pumps.Vacuolar acidification in Petunia petal epidermis cells is mediated by heterodimers consisting of two P-type H+-ATPases (P3A+ P3B).K+/H+ exchange by NHX-transporters is important for vacuolar potassium accumulation and pH homeostasis.Genetically encoded sensors allow in vivo pH-measurements in the different compartments of the endomembrane system.pH homeostasis is an essential process in all plant cells and the maintenance of correct luminal pH in the compartments of the endomembrane system is important not only for secondary active transport but also for a variety of cellular functions including protein modification, sorting, and trafficking. Due to their electrogenicity primary H+-pumps cannot establish and control the often large proton-gradients single-handedly but require the co-action of other ion transporters that serve as either shunt conductances or proton-leaks. Here, I will thus focus on recent results that highlight the interplay of proton-pumps and proton-coupled transporters in controlling pH in the compartments of the plant endomembrane system.