Working group session:
Functional Genomics
Presentation type:
oral
Authors:
Xu, Wen-Liang; Zhang, De-Jing; Qin, Li-Xia; Huang, Geng-Qing; Wu, Yanfeng; Li, Xue-Bao
Presenter:
Li, Xue-Bao
Correspondent:
Li, Xue-Bao
Abstract:
Proline-rich proteins (PRP) contribute to cell wall structure of specific cell types and are involved in plant growth and development. In this study, a fiber-specific gene, GhPRP5, encoding a proline-rich protein was functionally characterized in cotton. GhPRP5 promoter directed GUS expression only in trichomes of both transgenic Arabidopsis and tobacco plants. Subcellular localization showed that GhPRP5 protein was mainly localized on the plasma membrane. The transgenic Arabidopsis plants with overexpressing GhPRP5 displayed reduced cell growth, resulting in smaller cell size and consequently plant dwarfs, in comparison to wild-type plants. In contrast, knock-down of GhPRP5 expression by RNA interference in cotton enhanced fiber development. The lint fiber length of transgenic cotton lines was longer than that of wild type. Interestingly, the length of fuss fibers was also longer in transgenic lines. A yeast two-hybrid screen results suggested that GhPRP5 may form homodimers in cotton fiber cells. In addition, a number of genes that are involved in the cell wall-plasma membrane (PM)-cytoskeleton continuum were up-regulated or down-regulated in the transgenic cotton plants owing to suppression of GhPRP5. Collectively, these data suggested that GhPRP5 is involved in fiber development of cotton.