Arabidopsis NF-YCs play dual roles in repressing brassinosteroid biosynthesis and signaling during light-regulated hypocotyl elongation. Issue 7 (19th April 2021)

• Record Type: Journal Article
• Authors: Zhang, Wenbin; Tang, Yang; Hu, Yilong; Yang, Yuhua; Cai, Jiajia; Liu, Hailun; Zhang, Chunyu; Liu, Xu; Hou, Xingliang
• Is Part Of: The Plant Cell. Volume 33:Issue 7(2021)
• Page Start: 2360
• Page End: 2374
• Publication Date: 2021-04-19
• DOI: 10.1093/plcell/koab112
• Languages: English
• ISSNs: 1040-4651

Abstract

Abstract: Light functions as the primary environmental stimulus and brassinosteroids (BRs) as important endogenous growth regulators throughout the plant lifecycle. Photomorphogenesis involves a series of vital developmental processes that require the suppression of BR-mediated seedling growth, but the mechanism underlying the light-controlled regulation of the BR pathway remains unclear. Here, we reveal that nuclear factor YC proteins (NF-YCs) function as essential repressors of the BR pathway during light-controlled hypocotyl growth in Arabidopsis thaliana . In the light, NF-YCs inhibit BR biosynthesis by directly targeting the promoter of the BR biosynthesis gene BR6ox2 and repressing its transcription. NF-YCs also interact with BIN2, a critical repressor of BR signaling, and facilitate its stabilization by promoting its Tyr200 autophosphorylation, thus inhibiting the BR signaling pathway. Consistently, loss-of-function mutants of NF-YCs show etiolated growth and constitutive BR responses, even in the light. Our findings uncover a dual role of NF-YCs in repressing BR biosynthesis and signaling, providing mechanistic insights into how light antagonizes the BR pathway to ensure photomorphogenic growth in Arabidopsis. Abstract : NF-YC transcription factors function as essential repressors of the brassinosteroid biosynthesis and signaling pathways to mediate photomorphogenic growth in Arabidopsis.