文献类型： 外文期刊

作者： Li, Jieni ¹ ; Zhang, Yuexiong ³ ; Li, Zhenyong ¹ ; Dai, Hang ¹ ; Luan, Xin ⁴ ; Zhong, Tianxiu ¹ ; Chen, Shu ¹ ; Xie, Xin-Ming ¹ ; Qin, Gang ³ ; Zhang, Xiang-Qian ¹ ; Peng, Haifeng ⁵ ;

作者机构： 1.South China Agr Univ, Coll Forestry & Landscape Architecture, Guangzhou 510642, Peoples R China

2.Foshan Univ, Coll Food Sci & Engn, Guangdong Prov Key Lab Food Intelligent Mfg, Foshan 528000, Peoples R China

3.Guangxi Acad Agr Sci, Rice Res Inst, Guangxi Key Lab Rice Genet & Breeding, Nanning 530007, Peoples R China

4.Guangdong Acad Agr Sci, Rice Res Inst, Guangzhou 510640, Peoples R China

5.South China Agr Univ, Coll Life Sci, Guangdong Lab Lingnan Modern Agr, Guangzhou 510642, Peoples R China

关键词： Rice; Leucine-rich repeat extensin-like protein; Gibberellin; Lignin; Root growth

期刊名称：PLANT MOLECULAR BIOLOGY （ 影响因子：5.1； 五年影响因子：5.3 ）

ISSN： 0167-4412

年卷期： 2023 年

页码：

收录情况： SCI

摘要： Key messageOsPEX1 is a negatively regulator of root growth in rice. The antagonistic action of OsPEX1 expression level and gibberellin biosynthesis mediates lignin deposition in root cell. Leucine-rich repeat extensins (LRXs) are required for plant growth and development through affecting cell growth and cell wall formation. LRX gene family can be classified into two categories: predominantly vegetative-expressed LRX and reproductive-expressed PEX. In contrast to the tissue specificity of Arabidopsis PEX genes in reproductive organs, rice OsPEX1 is also highly expressed in roots in addition to reproductive tissue. However, whether and how OsPEX1 affects root growth is unclear. Here, we found that overexpression of OsPEX1 retarded root growth by reducing cell elongation likely caused by an increase of lignin deposition, whereas knockdown of OsPEX1 had an opposite effect on root growth, indicating that OsPEX1 negatively regulated root growth in rice. Further investigation uncovered the existence of a feedback loop between OsPEX1 expression level and GA biosynthesis for proper root growth. This was supported by the facts that exogenous GA(3) application downregulated transcript levels of OsPEX1 and lignin-related genes and rescued the root developmental defects of the OsPEX1 overexpression mutant, whereas OsPEX1 overexpression reduced GA level and the expression of GA biosynthesis genes. Moreover, OsPEX1 and GA showed antagonistic action on the lignin biosynthesis in root. OsPEX1 overexpression upregulated transcript levels of lignin-related genes, whereas exogenous GA(3) application downregulated their expression. Taken together, this study reveals a possible molecular pathway of OsPEX1mediated regulation of root growth through coordinate modulation of lignin deposition via a negative feedback regulation between OsPEX1 expression and GA biosynthesis.