《植物生理学报》 2018, 54(7): 1205-1212

过表达OsGRXC12对水稻侧根伸长的影响

杨亚军, 张盛春, 阳成伟^*

华南师范大学生命科学学院, 广东省植物发育生物工程重点实验室, 广州510631

通信作者：阳成伟；E-mail: yangchw@scnu.edu.cn

摘　要：

以粳稻品种‘中花11’为材料, 用逆转录法克隆获得OsGRXC12基因, 构建OsGRXC12过表达载体, 通过农杆菌介导转化愈伤组织获得纯合过表达植株。GUS染色和Real-time PCR分析表明, OsGRXC12在胚芽鞘、节、蘖、花蕊等幼嫩组织集中表达, 在根、叶、穗等成熟组织中表达量低; IAA和BR都严重抑制OsGRXC12表达。幼苗期过表达株系的侧根显著变短, 侧根和侧根原基数量不变; 激光共聚焦显微镜观察显示过表达株系的侧根根尖成熟区细胞明显变短, 伸长区细胞数量不变; 过表达株系中与侧根发育密切相关基因OsHO1的表达被严重抑制, BR处理能缓解OsGRXC12过量表达对OsHO1表达和侧根伸长的抑制。结果表明OsGRXC12和BR通过调节HO1表达, 共同调控水稻侧根伸长。

关键词：GRX; BR; HO1; 侧根伸长; 信号途径

收稿：2018-05-11   修定：2018-06-22

资助：国家自然科学基金(31670286)。

Effect of overexpressing OsGRXC12 on lateral root elongation in rice

YANG Ya-Jun, ZHANG Sheng-Chun, YANG Cheng-Wei ^*

Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou 510631, China

Corresponding author: YANG Cheng-Wei; E-mail: yangchw@scnu.edu.cn

Abstract:

The cDNA of OsGRXC12 was acquired from an Oryza sativa ssp. japonica variety ZH11 using reverse transcription method and an overexpressing vector containing OsGRXC12 was constructed successfully. The vector was subsequently introduced into the callus induced from rice mediated by Agrobacterium tumefaction and homozygous overexpressing lines were obtained. The results of GUS staining and Real-time PCR analysis indicated the expression levels of OsGRXC12 was high in young tissues such as coleoptile, node, tiller, pistil, and low in mature tissues such as root, leaf and spikelet. Both IAA and BR treatments severely inhibited OsGRXC12 expression. Compared to ZH11, in overexpressing seedlings, LR length significantly reduced, LR and LRP numbers unchanged. Laser confocal microscopy observation showed cortex and epidermis cells length in LR apical differentiation zone obviously decreased, epidermis cell number in LR apical elongation zone unchanged. The expression of HO1, a key enzyme gene closely related to LR development, was severely inhibited. BR treatment obviously alleviated the inhibitions on HO1 expression and LR elongation by overexpressing OsGRXC12. Our results suggested OsGRXC12 regulated LR elongation through modulating HO1 expression with BR.

Key words: GRX; BR; HO1; lateral root elongation; signal pathway