《植物生理学报》 2014, 50(10): 1515-1522

A类CLE多肽调节拟南芥根尖韧皮部的发育

吴云飞^1,2, 储黄伟², 周志刚¹, 梁婉琪², 张大兵^2,*

¹上海海洋大学水产与生命学院, 上海201306; ²上海交通大学生命科学技术学院, 上海200240

通信作者：张大兵；E-mail: zhangdb@sjtu.edu.cn；Tel: 021-34205073

摘　要：

CLE多肽是一类通过细胞间通讯来调节干细胞命运的多肽类激素信号分子。之前的研究结果表明CLE类多肽可以调节初生木质部发育, 然而CLE类多肽是否影响韧皮部发育还不清楚。本研究发现A类CLE多肽可以控制拟南芥根部初生韧皮部的形成, 用23种A类CLE多肽进行外源处理可以有效地抑制伸长区韧皮部前体细胞的形成。而且不同于控制初生木质部的形成机制, CLE多肽影响韧皮部发育并不依赖于细胞分裂素信号途径。这些结果表明原形成层细胞发育成初生木质部和初生韧皮部是通过两条不同的途径, 为研究CLE类基因对根维管束的形成和发育提供了新的见解。

关键词：CLE; 根; 维管组织; 韧皮部

收稿：2014-06-05   修定：2014-08-20

资助：国家自然科学基金激素重大研究计划项目(90717109)。 致谢 Ykä Helariutta教授馈赠APLpro::GUS植株, ABRC (Arabidopsis Biological Resource Center)提供SALK_058085C (ahp6-4)种子。

A-Type CLE Peptides Regulate the Phloem Development in Arabidopsis Root Tip

WU Yun-Fei^1,2, CHU Huang-Wei², ZHOU Zhi-Gang¹, LIANG Wan-Qi², ZHANG Da-Ding^2,*

¹College of Fisheries and Life Science, Shanghai Ocean University, Shanghai 201306, China; ²School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China

Corresponding author: ZHANG Da-Ding; E-mail: zhangdb@sjtu.edu.cn; Tel: 021-34205073

Abstract:

CLAVATA3/ENDOSPERM SURROUNDING REGION (CLE)-related peptides function as intercellular signaling molecules in regulating stem cell fates during plant development. Recently, increasing evidence suggests the role of CLE peptides in protoxylem development; however, the CLE molecule plays a role in phloem formation remains elusive. Here, we revealed an unknown function of A-type CLE peptides in modulating root protophloem patterning in Arabidopsis thaliana. Treatment of 23 A-type CLE peptides, including CLE40p, caused the inhibition of the differentiation of phloem precursor cells in root elongation zone. Furthermore, we showed that the inhibition of phloem formation by CLE40p may act through a cytokinin independent signaling pathway, which are responsible for the suppression of protoxylem vessel formation. These findings suggest that distinct signaling components are involved in controlling the differentiation of procambial cells into protoxylem and phloem in Arabidopsis roots. This work provides new insights into CLEs function in root vascular development.

Key words: CLE; root; vascular; phloem