Institute of Biochemistry and Biology, Plant Physiology, University of Potsdam, Karl-Liebknecht-Str. 24-25, Building 20, DE-14476 Potsdam-Golm, Germany.
Institute of Biochemistry and Biology, Plant Physiology, University of Potsdam, Karl-Liebknecht-Str. 24-25, Building 20, DE-14476 Potsdam-Golm, Germany; Umeå Plant Science Centre, Department of Plant Physiology, Umeå University, SE-90 187 Umeå, Sweden.
Curr Opin Plant Biol. 2018 Feb;41:46-53. doi: 10.1016/j.pbi.2017.08.002. Epub 2017 Sep 1.
Plant roots control uptake of water and nutrients and cope with environmental challenges. The root epidermis provides the first selective interface for nutrient absorption, while the endodermis produces the main apoplastic diffusion barrier in the form of a structure called the Casparian strip. The positioning of root hairs on epidermal cells, and of the Casparian strip around endodermal cells, requires asymmetries along cellular axes (cell polarity). Cell polarity is termed planar polarity, when coordinated within the plane of a given tissue layer. Here, we review recent molecular advances towards understanding both the polar positioning of the proteo-lipid membrane domain instructing root hair initiation, and the cytoskeletal, trafficking and polar tethering requirements of proteins at outer or inner plasma membrane domains. Finally, we highlight progress towards understanding mechanisms of Casparian strip formation and underlying endodermal cell polarity.
植物根控制水分和养分的吸收，并应对环境挑战。根表皮为养分吸收提供了第一个选择性界面，而内皮层则以内皮层条带（Casparian strip）的形式产生主要的质外体扩散屏障。根毛在表皮细胞上的定位，以及 Casparian 条带在根内皮层细胞上的定位，需要沿着细胞轴（细胞极性）的不对称性。当在给定组织层的平面内协调时，细胞极性被称为平面极性。在这里，我们回顾了最近在理解指导根毛起始的蛋白脂膜域的极性定位，以及外质膜域或内质膜域蛋白质的细胞骨架、运输和极性固定要求方面的分子进展。最后，我们强调了在理解 Casparian 条带形成和内皮层细胞极性的机制方面取得的进展。
