Premium
A brassinosteroid responsive miRNA‐target module regulates gibberellin biosynthesis and plant development
Author(s) -
Gao Jing,
Chen Hong,
Yang Huifang,
He Yong,
Tian Zhihong,
Li Jianxiong
Publication year - 2018
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/nph.15331
Subject(s) - brassinosteroid , gibberellin , signal transduction , gene , biology , promoter , microbiology and biotechnology , microrna , biosynthesis , regulation of gene expression , chemistry , gene expression , genetics , arabidopsis , mutant
Summary Plant growth and development are highly coordinated by hormones, including brassinosteroid ( BR ) and gibberellin ( GA ). Although much progress has been made in understanding the fundamental signaling transduction in BR and GA , their relationship remains elusive in rice. Here, we show that BR suppresses the level of OsmiR159d, which cleaves the target Os GAMYBL 2 gene. The OsmiR159d‐ Os GAMYBL 2 pair functions as an early BR ‐responsive module regulating the expression of BU 1 , a BR ‐regulated gene involved in BR signaling, and CPS 1 and GA 3ox2 , two genes in GA biosynthesis, by binding to the promoters of these genes. Furthermore, Os GSK 2, a key negative player in BR signaling, interacts with Os GAMYBL 2 and prevents it from being degraded under 24‐epibrassinolide treatment, whereas SLR 1, a rice DELLA protein negatively regulating GA signaling, interacts with Os GAMYBL 2 and prevents Os GAMYBL 2 from binding to the target gene promoter. GA signaling induces degradation of Os GAMYBL 2 and, consequently, enhances BR signaling. These results demonstrate that a BR ‐responsive module acts as a common component functioning in both BR and GA pathways, which connects BR signaling and GA biosynthesis, and thus coordinates the regulation of BR and GA in plant growth and development.