King Abdullah University of Science and Technology (KAUST), Division of Biological and Environmental Sciences and Engineering, Thuwal, 23955-6900, Kingdom of Saudi Arabia.
Plant Transport and Signalling Group, Australian Research Council (ARC) Centre of Excellence in Plant Energy Biology, School of Agriculture, Food and Wine, Waite Research Institute, University of Adelaide, Glen Osmond, SA 5064, Australia.
Trends Plant Sci. 2017 Mar;22(3):236-248. doi: 10.1016/j.tplants.2016.12.004. Epub 2017 Jan 9.
Chloride (Cl) is an essential plant nutrient but under saline conditions it can accumulate to toxic levels in leaves; limiting this accumulation improves the salt tolerance of some crops. The rate-limiting step for this process - the transfer of Cl from root symplast to xylem apoplast, which can antagonize delivery of the macronutrient nitrate (NO) to shoots - is regulated by abscisic acid (ABA) and is multigenic. Until recently the molecular mechanisms underpinning this salt-tolerance trait were poorly defined. We discuss here how recent advances highlight the role of newly identified transport proteins, some that directly transfer Cl into the xylem, and others that act on endomembranes in 'gatekeeper' cell types in the root stele to control root-to-shoot delivery of Cl.
氯（Cl）是一种必需的植物养分，但在盐胁迫条件下，它会在叶片中积累到有毒水平；限制这种积累可以提高一些作物的耐盐性。这个过程的限速步骤 - 将 Cl 从根共质体转移到木质部质外体，这会拮抗将大量营养物质硝酸盐（NO）输送到地上部 - 受到脱落酸（ABA）的调节，并且是多基因的。直到最近，这个耐盐性性状的分子机制还没有很好地定义。我们在这里讨论的是，最近的进展如何强调新发现的转运蛋白的作用，一些蛋白可以直接将 Cl 转移到木质部，而另一些蛋白则作用于根柱中的“守门员”细胞类型的内膜，以控制 Cl 从根到地上部的输送。
