GhMYB7 promotes secondary wall cellulose deposition in cotton fibres by regulating GhCesA gene expression through three distinct cis-elements

GhMYB7 promotes secondary wall cellulose deposition in cotton fibres by regulating GhCesA gene expression through three distinct cis-elements

© 2021 The Authors. New Phytologist © 2021 New Phytologist Foundation.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 232(2021), 4 vom: 25. Nov., Seite 1718-1737
1. Verfasser: Huang, Junfeng (VerfasserIn)
Weitere Verfasser: Chen, Feng, Guo, Yanjun, Gan, Xinli, Yang, Mingming, Zeng, Wei, Persson, Staffan, Li, Juan, Xu, Wenliang
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2021
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, Non-U.S. Gov't MYB cellulose synthesis cis-elements cotton fibre secondary cell wall Plant Proteins Cellulose 9004-34-6
Beschreibung
Zusammenfassung:© 2021 The Authors. New Phytologist © 2021 New Phytologist Foundation.
Cotton fibre is the most important source for natural textiles. The secondary cell walls (SCWs) of mature cotton fibres contain the highest proportion of cellulose content (> 90%) in any plant. The onset and progression of SCW cellulose synthesis need to be tightly controlled to balance fibre elongation and cell wall deposition. However, regulatory mechanisms that control cellulose synthesis during cotton fibre growth remain elusive. Here, we conducted genetic and functional analyses demonstrating that the R2R3-MYB GhMYB7 controls cotton fibre cellulose synthesis. Overexpression of GhMYB7 in cotton sped up SCW cellulose biosynthesis in fibre cells, and led to shorter fibres with thicker walls. By contrast, RNA interference (RNAi) silencing of GhMYB7 delayed fibre SCW cellulose synthesis and resulted in elongated fibres with thinner walls. Furthermore, we demonstrated that GhMYB7 regulated cotton fibre SCW cellulose synthases by directly binding to three distinct cis-elements in the respective GhCesA4, GhCesA7 and GhCesA8 promoters. We found that this regulatory mechanism of cellulose synthesis was 'hi-jacked' also by other GhMYBs. Together, our findings uncover a hitherto-unknown mechanism that cotton fibre employs to regulate SCW cellulose synthesis. Our results also provide a strategy for genetic improvement of SCW thickness of cotton fibre
Beschreibung:Date Completed 27.10.2021
Date Revised 27.10.2021
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/nph.17612