AtLAZY1 is a signaling component required for gravitropism of the Arabidopsis thaliana inflorescence
AtLAZY1 is a signaling component required for gravitropism of the Arabidopsis thaliana inflorescence
复制标题
DOI：
10.1111/tpj.12118
复制
发表时间：
2013-04-01
期刊：
影响因子：
7.2
通讯作者：
Iino, Moritoshi
中科院分区：
文献类型：
--
作者：
Yoshihara, Takeshi;Spalding, Edgar P.;Iino, Moritoshi
本研究确定了一个六口之家A.拟南芥基因与LAZY 1共享五个有限的序列相似区域，LAZY 1是水稻（水稻）中的一个基因，显示参与茎向地性的早期重力信号传导。将T-DNA插入到与LAZY 1最相似的拟南芥基因（At 5g 14090）中将花序分支角度从野生型值42度增加到81度。RNA干扰线和分子拯救实验证实了分支角表型和基因之间的联系，因此命名为AtLAZY 1。atlazy 1下胚轴和初级花序茎的时间分辨向重力性测量结果表明，在第一个小时的响应弯曲率显着降低。研究AtLAZY 1蛋白的亚细胞定位以确定从基因序列预测的核定位是否是可观察的并且对其在芽重力响应中的功能是重要的。AtLAZY 1融合到绿色荧光蛋白在很大程度上挽救了atlazy 1的分支角表型，并通过共聚焦显微镜在细胞周边和细胞核内观察到。核定位信号的突变阻止了细胞核中可检测水平的AtLAZY 1，而不影响该基因拯救atlazy 1分支角表型的能力。这些结果表明，AtLAZY 1功能的重力信号在地上部向重力性，是一个功能的直向同源物的水稻LAZY 1。蛋白质的核池似乎对这种功能是不必要的，相反，它依赖于似乎驻留在细胞外围的池。
The present study identified a family of six A. thaliana genes that share five limited regions of sequence similarity with LAZY1, a gene in Oryza sativa (rice) shown to participate in the early gravity signaling for shoot gravitropism. A T-DNA insertion into the Arabidopsis gene (At5g14090) most similar to LAZY1 increased the inflorescence branch angle to 81 degrees from the wild type value of 42 degrees. RNA interference lines and molecular rescue experiments confirmed the linkage between the branch-angle phenotype and the gene consequently named AtLAZY1. Time-resolved gravitropism measurements of atlazy1 hypocotyls and primary inflorescence stems showed a significantly reduced bending rate during the first hour of response. The subcellular localization of AtLAZY1 protein was investigated to determine if the nuclear localization predicted from the gene sequence was observable and important to its function in shoot gravity responses. AtLAZY1 fused to green fluorescent protein largely rescued the branch-angle phenotype of atlazy1, and was observed by confocal microscopy at the cell periphery and within the nucleus. Mutation of the nuclear localization signal prevented detectable levels of AtLAZY1 in the nucleus without affecting the ability of the gene to rescue the atlazy1 branch-angle phenotype. These results indicate that AtLAZY1 functions in gravity signaling during shoot gravitropism, being a functional ortholog of rice LAZY1. The nuclear pool of the protein appears to be unnecessary for this function, which instead relies on a pool that appears to reside at the cell periphery.