Working group session:
Functional Genomics
Presentation type:
oral
Authors:
Guan, Xueying; Chen, Z. Jeffrey; Fang, Lei; An, Nicholas; Hyon, Steven; Kim, Timothy ; Pang, Mingxiong
Presenter:
Guan, Xueying
Correspondent:
Chen, Z. Jeffrey
Abstract:
Cotton is the largest renewal source of textile fiber and a significant oil seed crop. Cotton improvement is hindered by the large and complex tetraploid genomes. Recent studies have shown that development of seed hair (fiber) in cotton share many molecular similarities with the development of leaf trichomes in Arabidopsis. Given the plethora amount of genetic and genomic resources in Arabidopsis, we developed a systematic approach to identify functional homologues of cotton genes in Arabidopsis thaliana. The system is known as cotton full-length cDNA over-expression (cFOX) in A. thaliana. We converted a cotton (Gossypium hirsutum L. cv. TM-1) library of full-length cDNA that are expressed in young ovules and immature fibers into a binary vector and transformed the full cotton cDNAs into A. thaliana in three genetic backgrounds, Col-0 wild-type, the hairless glabrous1 (gl1) mutant, and the hairy triptchon (try) mutant. In an initial screen, we analyzed 608 transgenic lines in Col-0, 866 lines in gl1,and 497 lines in try and identified 46 lines with stably altered phenotypes in two additional generations. In 20 lines, the cotton cDNA inserts were recovered by genomic PCR and cloned. These cotton genes were grouped infunctional categories of phytohormone signaling, lipid metabolism, and transcription factors, many of which are expressed in early stages of fiber development. The observed phenotypes corresponding with the cotton cDNA inserts are consistent with the known functions and expression patterns of these genes. Experiments are underway to validate functions for these cotton genes in Arabidopsis and cotton. The systematic screen will be expanded to identify novel cotton genes, especially related to trichome and fiber cell development. The cFOX system will become a valuable resource for discovering functions of cotton genes, improving functional annotation of cotton genes,and providinga translational repository of cotton genes in Arabidopsis.