Control of plant trichome development by a cotton fiber MYB gene

• Published in: The Plant cell Vol. 16; no. 9; pp. 2323 - 2334
• Main Authors: Wang, S, Wang, J.W, Yu, N, Li, C.H, Li, Y.C, Luo, B, Guo, J.Y, Wang, L.J, Chen, X.Y
• Format: Journal Article
• Language: English
• Published: United States American Society of Plant Biologists 01.09.2004
• Subjects: Amino Acid Motifs - genetics; Arabidopsis thaliana; beta-glucuronidase; cell differentiation; cell growth; Cotton; Cotton fibers; Enhancer Elements, Genetic - genetics; Evolution, Molecular; Fiber cells; Fibers; Gene expression regulation; Gene Expression Regulation, Plant - genetics; Gene Transfer Techniques; Genes; Genes, myb - genetics; Genes, myb - physiology; Gossypium - genetics; Gossypium - growth & development; Gossypium - ultrastructure; Gossypium arboreum; Gossypium hirsutum; Introns; Introns - genetics; leaves; messenger RNA; Microscopy, Electron, Scanning; Molecular Sequence Data; myb genes; Phylogeny; Plant cells; Plants; Plants, Genetically Modified - genetics; Plants, Genetically Modified - growth & development; Plants, Genetically Modified - metabolism; promoter regions; Promoter Regions, Genetic - genetics; Protein Structure, Tertiary - genetics; reporter genes; Repressor Proteins - genetics; seed trichomes; seeds; Seeds - genetics; Seeds - growth & development; Seeds - ultrastructure; transcription (genetics); transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; transcriptional activation; transgenic plants; Trichomes; Yeasts
• ISSN: 1040-4651; 1532-298X; 1532-298X
• DOI: 10.1105/tpc.104.024844

Cotton (Gossypium spp) plants produce seed trichomes (cotton fibers) that are an important commodity worldwide; however, genes controlling cotton fiber development have not been characterized. In Arabidopsis thaliana the MYB gene GLABRA1 (GL1) is a central regulator of trichome development. Here, we show that promoter of a cotton fiber gene, RD22-like1 (RDL1), contains a homeodomain binding L1 box and a MYB binding motif that confer trichome-specific expression in Arabidopsis. A cotton MYB protein GaMYB2/Fiber Factor 1 transactivated the RDL1 promoter both in yeast and in planta. Real-time PCR and in situ analysis showed that GaMYB2 is predominantly expressed early in developing cotton fibers. After transferring into Arabidopsis, GL1::GaMYB2 rescued trichome formation of a gl1 mutant, and interestingly, 35S::GaMYB2 induced seed-trichome production. We further demonstrate that the first intron of both GL1 and GaMYB2 plays a role in patterning trichomes: it acts as an enhancer in trichome and a repressor in nontrichome cells, generating a trichome-specific pattern of MYB gene expression. Disruption of a MYB motif conserved in intron 1 of GL1, WEREWOLF, and GaMYB2 genes affected trichome production. These results suggest that cotton and Arabidopsis use similar transcription factors for regulating trichomes and that GaMYB2 may be a key regulator of cotton fiber development.