博文

Tree Physiology：PtoWOX5a参与杨树中不定根的发育

已有 4432 次阅读 2017-9-29 08:32 |个人分类:每日摘要|系统分类:论文交流

The WUSCHEL-related homeobox 5a (PtoWOX5a) is involved in adventitious root development in poplar

First author:Jianbo Li; Affiliations: Chinese Academy of Forestry (中国林业科学研究院): Beijing, China

Corresponding author: Mengzhu Lu (卢孟柱)

Adventitious rooting (不定根) is an essential step in vegetative propagation (无性繁殖). Currently, the mechanism that regulates adventitious root (AR) development in woody plants is poorly understood. This work demonstrates that Populus tomentosa (毛白杨) WUSCHEL-related homeobox 5a (PtoWOX5a) transcription factor is involved in AR development in poplar. PtoWOX5a was specifically expressed in the AR tip and lateral root tip during AR and lateral root regeneration (再生) from the stem segment (茎段). Phenotypic complementation experiments indicated that the PtoWOX5a can functionally complement AtWOX5 in quiescent center (QC; 静止中心) cells. Overexpression of PtoWOX5a introduces significant developmental phenotypes in roots and leaves, such as increased AR number, decreased AR length, swollen (膨胀的) AR tip and lateral root tip, and decreased leaf number and area. The conserved mechanism of D-type cyclins (CYCD) repression mediated by WOX5 was confirmed in poplar. The co-expression network of PtWOX5a was constructed, which provided clues to reveal the molecular mechanism of PtoWOX5a in AR development in poplar. Taken together, our results suggest that the PtoWOX5a is involved in AR development though cooperating with a series of functional genes.

不定根形成与发育是无性繁殖的一个必要阶段。现在，我们对于调控木本植物不定根发育的机制还所知甚少。本研究表明毛白杨的转录因子PtoWOX5a参与杨树中的不定根发育。在不定根和侧根发育从茎段再生时，PtoWOX5a特异性在基因特异性在不定根和侧根的根尖表达。表型互不试验显示PtoWOX5a可以在静止中心细胞互补AtWOX5的功能。过表达PtoWOX5a基因会诱导显著的根与叶的发育表型，比如不定根数量上升，不定根长度缩短，不定根与侧根的根尖膨大，叶的数量和面积减少。作者还在杨树中确定了由WOX5介导的CYCD基因抑制机制。作者构建了PtWOX5a基因的共表达网络，为PtoWOX5a介导的杨树不定根发育调控机制提供线索。综上，本文表明PtoWOX5a基因通过与一些列的功能基因共同作用于不定根的发育。

通讯：卢孟柱 (http://skltgb.caf.ac.cn/content/yanjiuduiwu/zhuanjiafengcai/201306u84.shtml)