The transcription factor GhMYB4 represses lipid transfer and sucrose transporter genes and inhibits fiber cell elongation in cotton
转录因子GhMYB4抑制棉花脂质转运和蔗糖转运基因及纤维细胞伸长
- 关键词：
- 来源：
- PLANT PHYSIOLOGY
- 类型：
- 学术文献
- 语种：
- 英语
- 原文发布日期：
- 2024-12-11
- 摘要：
- Cotton (Gossypium hirsutum) fiber is a highly elongated single cell with a thickened cell wall. MYB transcription factors are important regulators of plant cell elongation; however, the molecular mechanism involved in regulating fiber elongation remains to be explored. Here, we present evidence that the R2R3-MYB transcription factor GhMYB4 negatively regulates cotton fiber cell elongation by suppressing the expression of 2 crucial genes previously reported to affect fiber development: lipid transfer protein 4 (GhLTP4) and sucrose transporter 12 (GhSWEET12). GhMYB4 is preferentially expressed in elongating fiber cells. Knockdown of GhMYB4 in cotton results in longer fiber cells, whereas overexpression of GhMYB4 in Arabidopsis leads to reduced plant height and root length. Transcriptomic and lipidomic analyses revealed that GhMYB4 is involved in coordinating 3 interconnected biological processes, namely lipid content regulation, auxin signaling, and sugar metabolism. Additionally, we showed that GhMYB4 inhibits the expression of GhLTP4 and GhSWEET12 by binding to the MYB cis-element (TTTAGTG) in their respective promoters. Interestingly, basic helix-loop-helix transcription factor 105 (GhbHLH105) and MYB transcription factor 212 (GhMYB212) counteract the inhibitory effects of GhMYB4 on the expression of GhLTP4 and GhSWEET12, respectively. These findings provide insights into the complex molecular mechanisms regulating plant cell elongation.The interplay between 2 transcription factors modulates the gene expression of a lipid transfer protein and a sucrose transporter, ultimately regulating fiber cell elongation in cotton.
- 所属专题：
- 171
