Genome-wide analysis of gene expression of EMS-induced short fiber mutant Ligon lintless-y (li) in cotton (Gossypium hirsutum L.).

In this work we describe a chemically-induced short fiber mutant cotton line, Ligon-lintless-y (li), which is controlled by a single recessive locus and affects multiple traits, including height of the plant, and length and maturity of fiber. An RNAseq analysis was used to evaluate global transcriptional changes during cotton fiber development at 3, 8 and 16days post anthesis. We found that 613, 2629 and 3397 genes were significantly down-regulated, while 2700, 477 and 3260 were significantly up-regulated in li at 3, 8 and 16 DPA. Gene set enrichment analysis revealed that many metabolic pathways, including carbohydrate, cell wall, hormone metabolism and transport were substantially altered in li developing fibers. We discuss perturbed expression of genes involved in signal transduction and biosynthesis of phytohormones, such as auxin, abscisic acid, gibberellin and ethylene. The results of this study provide new insights into transcriptional regulation of cotton fiber development.