Frontiers in Plant Science (Jul 2021)

DELLA-NAC Interactions Mediate GA Signaling to Promote Secondary Cell Wall Formation in Cotton Stem

  • Yi Wang,
  • Wanting Yu,
  • Lingfang Ran,
  • Zhong Chen,
  • Chuannan Wang,
  • Yang Dou,
  • Yuanyuan Qin,
  • Qingwei Suo,
  • Yaohua Li,
  • Jianyan Zeng,
  • Aimin Liang,
  • Yonglu Dai,
  • Yiping Wu,
  • Xufen Ouyang,
  • Yuehua Xiao

DOI
https://doi.org/10.3389/fpls.2021.655127
Journal volume & issue
Vol. 12

Abstract

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Gibberellins (GAs) promote secondary cell wall (SCW) development in plants, but the underlying molecular mechanism is still to be elucidated. Here, we employed a new system, the first internode of cotton, and the virus-induced gene silencing method to address this problem. We found that knocking down major DELLA genes via VIGS phenocopied GA treatment and significantly enhanced SCW formation in the xylem and phloem of cotton stems. Cotton DELLA proteins were found to interact with a wide range of SCW-related NAC proteins, and virus-induced gene silencing of these NAC genes inhibited SCW development with downregulated biosynthesis and deposition of lignin. The findings indicated a framework for the GA regulation of SCW formation; that is, the interactions between DELLA and NAC proteins mediated GA signaling to regulate SCW formation in cotton stems.

Keywords