Brassinosteroid signaling regulates shoot apical meristem homeostasis via orchestrating cytokinin and WUSCHEL activity.

Authors

Xin Wang, Jiaxin Liu, Hanyang Zhao, Yiqing Tang, Yutong Jiang, Tao Zhu, Xingjun Tian, Dijun Chen, Wenhui Lin, Bo Sun

Published in

Science advances. Volume 12. Issue 26. Pages eaed5120. Jun 26, 2026. Epub Jun 24, 2026.

Abstract

In flowering plants, the shoot apical meristem (SAM) is maintained through cross-talk between the stem cell identity gene WUSCHEL (WUS) and several phytohormone-signaling pathways. However, whether the well-known sterol phytohormone brassinosteroid (BR) signaling directly regulates SAM activity remains mysterious. Here, we showed that BR signaling maintains SAM homeostasis through both enhancing WUS expression and modulating WUS activity in organizing center. Plants with compromised BR signaling exhibited reduced SAM size, prematurely terminated SAM, and decreased total flower numbers. BRs synergize with cytokinin (CK) to activate WUS expression via a protein complex formed by the BR transcription factor brassinazole-resistant 1 (BZR1) and the CK-responsive factor Arabidopsis response regulator 1 (ARR1). In addition, BR promotes nuclear accumulation of BZR1-WUS protein complex, which binds E-box (CANNTG) motifs genome-wide and represses type A ARRs and FRUITFUL, thereby sustaining CK output and delaying SAM arrest. This BZR1-WUS module under BR signaling is conserved in tomatoes, revealing a general regulatory mechanism of SAM maintenance by BR signaling.

PMID:
42341129
Bibliographic data and abstract were imported from PubMed on 25 Jun 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.