Open AccessBrassinosteroid signaling integrates multiple pathways to release apical dominance in tomato
Author(s) -
Xiaojian Xia,
Han Dong,
Yanling Yin,
Xuchen Song,
Xiang Gu,
Kangqi Sang,
Jie Zhou,
Kai Shi,
Yanhong Zhou,
Christine H. Foyer,
Jingquan Yu
Publication year - 2021
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2004384118
Subject(s) - brassinosteroid , apical dominance , regulator , auxin , biology , microbiology and biotechnology , dominance (genetics) , transcription factor , signal transduction , master regulator , botany , biochemistry , shoot , arabidopsis , gene , mutant
Significance For almost a century, auxin had been well-known as the master regulator of apical dominance. Recently, however, sugars were shown to be the initial regulator of apical dominance, while strigolactones (SLs) and cytokinins (CKs) act downstream of auxin to control bud outgrowth. However, the interactions of the different pathways have remained outstanding questions. Here, we report that brassinosteroids (BRs) are essential for the release of apical dominance in tomato. CK signaling relays information from auxin, SL, and sugars to promote the production of BRs, which activate the BZR1 transcription factor to suppress the expression ofBRANCHED1 , an inhibitor of bud outgrowth. These findings demonstrate that hormonal and metabolic pathways impinge on a common BR signaling for controlling shoot branching.