Genomi-wide Investigation And Expression Analysis Of R2R3-MYB And CSD Gene Family Related Development Of Cotton Fiber

Cotton(Gossypium spp.) is not only an important economic crop, but also a excellent model plant for the study on genome polyploidizations, epidermal cell fate determination, cell elongation and cell wall development。With the whole-genome sequencing of Gossypium hirsutum, it provides us a opportunity to conduct genome-wide systematic gene famliy analysis in cotton genome and screen out genes related the development of cotton fiber, to lay the foundation for improving the quality of cotton fiber by used the Genetic engineering.The main research results are as follows:(1)We performed for a identify and expression analysis of R2R3-MYB gene family in Gossypium hirsutum. In this paper, we indentified 326 R2R3-MYB genes s in in Gossypium hirsutum genome, we further investigate the expression patterns of R2R3-MYB gene family at diffirent development stage of cotton fiber. We discern 5 genes which have highly expression level in cotton fiber. In order to vertify the credibility of transcriptome data, the quantitative real time PCR was performed for these genes at diffirent development stage of cotton fiber, we found that the result of quantitative real time PCR is consistent with transcriptome data, according to the result of transcriptome data analysis and quantitative rea Sl time PCR, we choose the Gh MYB42 gene as the object of study. Then, we clone Gh MYB42 gene and also construct the expression vector of Gh MYB42 gene..(2)In this study, we performed for the first time a genome-wide analysis of CAD gene family in cotton. A total of 21 CAD encoding genes were identified in Gossypium hirsutum. The phylogenic evolution, chromosome distribution, gene duplication and gene structure of CAD gene family were further to analysis. CAD gene family can be clustered into 7 major subgroups and the genes which have similar function were in same subgroup. Both tandem duplications and segmental duplications are found to attribute to the expansion of CAD gene family. CAD gene family have expression at different stage of development fiber. The Atcad5 mutant has a longer root hair than wild type. CAD genes maybe are involved in developing fiber and play a role in regulating the development of fiber.We performed for a identify and expression analysis of R2R3-MYB and CAD gene family in Gossypium hirsutum. We select genes involved in fiber development for further study and lay the foundation for modified fiber by used these genes.