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Cotton fiber provides the predominant plant textile in the world, and it is also a model for plant cell wall biosynthesis. The development of the single-celled cotton fiber takes place across several overlapping but discrete stages, including fiber initiation, elongation, the transition from elongation to secondary cell wall formation, cell wall thickening, and maturation and cell death. During each stage, the developing fiber undergoes a complex restructuring of genome-wide gene expression change and physiological/biosynthetic processes, which ultimately generate a strikingly elongated and nearly pure cellulose product that forms the basis of the global cotton industry. Here, we provide an overview of this developmental process focusing both on its temporal as well as evolutionary dimensions. We suggest potential avenues for further improvement of cotton as a crop plant.
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This content will become publicly available on December 1, 2025
Strigolactone promotes cotton fiber cell elongation by de-repressing DWARF53 on linolenic acid biosynthesis
Strigolactone (SL) is a plant hormone required for plant development. DWARF53 (D53) functions as a transcription repressor in SL signaling. However, the role of D53 in cotton (Gossypium hirsutum, Gh) fiber development remains unclear. Here, we identify that GhD53 suppresses fiber elongation by repressing transcription of GhFAD3 genes, which control linolenic acid (C18:3) biosynthesis. Mechanistically, GhD53 interacts with SL-related transcriptional activate factor (GhSLRF) to prevent its binding on Omega-3 fatty acid desaturase gene (GhFAD3) promoters, thereby inhibiting GhFAD3 transcription. Upon SL exposure, GhD53 is degraded and leads to GhSLRF activation. This activation further promotes GhFAD3 transcription, C18:3 biosynthesis, and fiber elongation. Our findings identify the molecular mechanism of how SL controls cell elongation via D53 and offer potential strategies to improve cotton quality through SL application.
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- Award ID(s):
- 2238942
- PAR ID:
- 10566983
- Publisher / Repository:
- Elsevier B.V.
- Date Published:
- Journal Name:
- Developmental Cell
- ISSN:
- 1534-5807
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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