Hubei Key Laboratory of Genetic Regulation and Integrative Biology, College of Life Sciences, Central China Normal University, Wuhan, China.
Plant Mol Biol. 2013 Jul;82(4-5):353-65. doi: 10.1007/s11103-013-0066-8. Epub 2013 Apr 29.
Proline-rich proteins 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. The transgenic Arabidopsis plants with overexpressing GhPRP5 displayed reduced cell growth, resulting in smaller cell size and consequently plant dwarfs, in comparison with wild type plants. In contrast, knock-down of GhPRP5 expression by RNA interference in cotton enhanced fiber development. The fiber length of transgenic cotton plants was longer than that of wild type. In addition, some genes involved in fiber elongation and wall biosynthesis of cotton were up-regulated or down-regulated in the transgenic cotton plants owing to suppression of GhPRP5. Collectively, these data suggested that GhPRP5 protein as a negative regulator participates in modulating fiber development of cotton.
富含脯氨酸的蛋白质有助于特定细胞类型的细胞壁结构，并参与植物的生长和发育。在这项研究中，我们对棉花中的纤维特异性基因 GhPRP5 进行了功能表征，该基因编码一种富含脯氨酸的蛋白质。GhPRP5 启动子仅在转基因拟南芥和烟草植物的毛状体中指导 GUS 表达。与野生型植物相比，过表达 GhPRP5 的转基因拟南芥植物的细胞生长减少，导致细胞尺寸变小，从而导致植株矮小。相比之下，通过 RNA 干扰敲低 GhPRP5 在棉花中的表达增强了纤维发育。转基因棉花植物的纤维长度长于野生型植物。此外，由于 GhPRP5 的抑制，一些参与棉花纤维伸长和细胞壁生物合成的基因在转基因棉花植物中上调或下调。总的来说，这些数据表明 GhPRP5 蛋白作为一个负调节剂参与调节棉花纤维的发育。
