DWARF53 interacts with transcription factors UB2/UB3/TSH4 to regulate maize tillering and tassel branching. Issue 2 (8th June 2021)

• Record Type: Journal Article
• Authors: Liu, Yuting; Wu, Guangxia; Zhao, Yongping; Wang, Hu Hailing; Dai, Zhouyan; Xue, Weicong; Yang, Juan; Wei, Hongbin; Shen, Rongxin; Wang, Haiyang
• Is Part Of: Plant physiology. Volume 187:Issue 2(2021)
• Page Start: 947
• Page End: 962
• Publication Date: 2021-06-08
• Subjects: Plant physiology -- Periodicals; Botany -- Periodicals; Periodicals; Electronic journals; 571.2
• DOI: 10.1093/plphys/kiab259
• Languages: English
• ISSNs: 0032-0889

Abstract

Abstract: Strigolactones (SLs) are a recently identified class of phytohormones that regulate diverse developmental processes in land plants. However, the signaling mechanism of SLs in maize ( Zea mays ) remains largely unexplored. Here, we identified the maize gene DWARF 53 ( ZmD53 ) and demonstrated that ZmD53 interacts with the SL receptors DWARF 14A/B (ZmD14A/B) in a rac -GR24-dependent manner. Transgenic maize plants expressing a gain-of-function mutant version of Zmd53 exhibited insensitivity to exogenous rac -GR24 treatment and a highly pleiotropic phenotype, including excess tillering and reduced tassel branching, indicating that ZmD53 functions as an authentic SL signaling repressor in maize. In addition, we showed that ZmD53 interacts with two homologous maize SPL transcription factors, UB3 and TSH4, and suppresses their transcriptional activation activity on TB1 to promote tillering. We also showed that UB2, UB3, and TSH4 can physically interact with each other and themselves, and that they can directly regulate the expression of TSH4, thus forming a positive feedback loop. Furthermore, we demonstrated that ZmD53 can repress the transcriptional activation activity of UB3 and TSH4 on their own promoters, thus decreasing tassel branch number. Our results reveal new insights into the integration of SL signaling and the miR156/SPL molecular module to coordinately regulate maize development. Abstract : Molecular and genetic analyses reveal DWARF53 defines a nexus of strigolactone signaling and UB2/UB3/TSH4-mediated signaling integration to regulate tillering and tassel branching in maize.