Characterization of a novel gravitropic mutant of morning glory, weeping2
Characterization of a novel gravitropic mutant of morning glory, weeping2
复制标题
DOI：
10.1016/j.asr.2007.10.029
复制
发表时间：
2008-09-15
影响因子：
2.6
通讯作者：
Takahashi, Hideyuki
中科院分区：
文献类型：
--
作者：
Kitazawa, Daisuke;Miyazawa, Yutaka;Takahashi, Hideyuki
在高等植物中，重力是控制生长方向的主要环境线索，这种现象称为向重力性。有人认为，重力也影响形态发生的其他方面，如回旋和缠绕运动。以前，我们表明，这些方面的植物生长形态需要淀粉体沉降内gravisensing内胚层细胞。然而，重力响应的分子机制及其与回旋章动和缠绕的关系仍然不清楚。在这里，我们的特点是一个新的芽向重力突变体牵牛花，weeping2（we2）。在we2突变体中，茎的向重力性反应不存在，下胚轴表现出严重降低的向重力性反应，而根表现出正常的向重力性。与我们以前的研究一致，我们发现we2突变体在茎的旋转和缠绕方面存在缺陷。组织学分析显示we2突变体形成异常的内胚层细胞。我们确定了一个突变的牵牛花同源短根（PnSHRI），这是遗传连锁的agravitropic表型的we2突变体，这可能是这种植物的内胚层细胞的异常分化的基础。这些结果表明，we2突变体的表型是由于PnSHRI的突变，PnSHRI调节妊娠形态发生，包括回旋和缠绕运动，在牵牛花。(C)空间研委会。由爱思唯尔有限公司出版。保留所有权利。
In higher plants, gravity is a major environmental cue that governs growth orientation, a phenomenon termed gravitropism. It has been suggested that gravity also affects other aspects of morphogenesis, such as circumnutation and winding movements. Previously, we showed that these aspects of plant growth morphology require amyloplast sedimentation inside gravisensing endodermal cells. However, the molecular mechanism of the graviresponse and its relationship to circumnutation and winding remains obscure. Here, we have characterized a novel shoot gravitropic mutant of morning glory,weeping2 (we2). In the we2 mutant, the gravitropic response of the stem was absent, and hypocotyls exhibited a severely reduced gravitropic response, whereas roots showed normal gravitropism. In agreement with our previous studies, we found that we2 mutant has defects in shoot circumnutation and winding. Histological analysis showed that we2 mutant forms abnormal endodermal cells. We identified a mutation in the morning glory homolog of SHORT-ROOT (PnSHRI) that was genetically linked to the agravitropic phenotype of we2 mutant, and which may underlie the abnormal differentiation of endodermal cells in this plant. These results suggest that the phenotype of we2 mutant is due to a mutation of PnSHRI, and that PnSHRI regulates gravimorphogenesis, including circumnutation and winding movements, in morning glory. (C) 2008 COSPAR. Published by Elsevier Ltd. All rights reserved.