Lim Chae Woo, Lee Sung Chul
Department of Life Science (BK21 Program), Chung-Ang University, Seoul, South Korea.
Front Plant Sci. 2020 Sep 25;11:587620. doi: 10.3389/fpls.2020.587620. eCollection 2020.
has 14 abscisic acid (ABA) receptors-PYR1/PYLs/RCARs-which have diverse and redundant functions in ABA signaling; however, the precise role of these ABA receptors remains to be elucidated. Here, we report the functional characterization of RCAR5/PYL11 in response to cold stress. Expression of gene in dry seeds and leaves was ABA-dependent and ABA-independent, respectively. Under cold stress conditions, seed germination was negatively affected by the level of expression, which was dependent on ABA and was regulated by HAB1, OST1, and ABI5-downstream components of RCAR5 in ABA signaling. Leaves of -overexpressing plants showed enhanced stomatal closure-independent of ABA-and high expression levels of cold, dehydration, and/or ABA-responsive genes compared to those of wild-type; these traits conferred enhanced freezing tolerance. Our data suggest that RCAR5 functions in response to cold stress by delaying seed germination and inducing rapid stomatal closure ABA-dependent and ABA-independent pathways, respectively.
植物有14种脱落酸（ABA）受体——PYR1/PYLs/RCARs——它们在ABA信号传导中具有多样且冗余的功能；然而，这些ABA受体的确切作用仍有待阐明。在此，我们报告了RCAR5/PYL11对冷胁迫响应的功能特性。该基因在干燥种子和叶片中的表达分别依赖于ABA和不依赖于ABA。在冷胁迫条件下，种子萌发受到该基因表达水平的负面影响，这种影响依赖于ABA，并受ABA信号传导中RCAR5的下游组分HAB1、OST1和ABI5调控。与野生型相比，过表达该基因的植株叶片表现出不依赖于ABA的气孔关闭增强，以及冷、脱水和/或ABA响应基因的高表达水平；这些特性赋予了增强的抗冻性。我们的数据表明，RCAR5分别通过延迟种子萌发和诱导快速气孔关闭，在依赖ABA和不依赖ABA的途径中对冷胁迫作出响应。
