中文摘要：

植物荷尔蒙在棉花纤维生长和开发起重要作用。然而，植物激素的相互作用在直到现在的纤维房间大部分是未知的。DELLA 蛋白质是在信号 transduction，它是也由另外的植物激素调整了的 GA (gibberellic 酸) 的批评部件，例如植物生长素和乙烯。在棉花纤维生长和开发理解 DELLA 基因的规定，我们从高地棉花克隆四 DELLA 基因纤维(Gossypium hirsutum L.) ，命名 GhGAI1， GhGAI2， GhGAI3，和 GhGAI4。有在各种各样的种类的另外的报导 DELLA 蛋白质的四预言的蛋白质的排列显示了那他们分享了保存领域和高相同。在象在不同阶段的棉花纤维一样的各种各样的纸巾和机关的四 GhGAIs 的表示侧面显示了那 GhGAI1 在所有检测样品比另外的 GhGAIs 有更高的 transcriptional 层次。而且， GhGAI1 的表达式水平显著地在 0 dpa (天帖子开花期) 被减少由 IAA 和 epi-BL 的增加的小卵，和外长的 epi-BL 减少了在 7 dpa 纤维的 GhGAI1 水平。同样，在 0 颗 dpa 小卵和 7 dpa 纤维的另外的三 GhGAIs 的层次被应用植物激素也调整。另外， GhGAI1 的层次从 1 ～ 3 颗 dpa 小卵比在 FL (Gossypium hirsutum 对 Xuzhou 142 ) 在 Xuzhou142 fl 异种(fuzzless-lintless ) 是更高的，建议 GhGAI1 从事了棉花纤维房间开始。这些结果显示 DELLA 基因涉及不同植物激素调整的纤维房间开始和延伸的过程。

英文摘要：

Plant hormones play important roles in cotton fiber growth and development.However,the interaction of phytohormones is largely unknown in fiber cells up to now.DELLA proteins are critical component in GA （gibberellic acid） signal transduction,which are also regulated by other phytohormones,such as auxin and ethylene.To understand the regulation of DELLA genes in cotton fiber growth and development,we cloned four DELLA genes from upland cotton fibers （Gossypium hirsutum L.）,named GhGAI1,GhGAI2,GhGAI3,and GhGAI4.Alignment of the four predicted proteins with other reported DELLA proteins in various species displayed that they shared conserved domains and high homology.Expression profiles of the four GhGAIs in various tissues and organs as well as cotton fibers in different stages displayed that GhGAI1 has higher transcriptional levels than other GhGAIs in all detected samples.Furthermore,the expression level of GhGAI1 was significantly reduced in 0 dpa （day post anthesis） ovules by addition of IAA and epi-BL,and exogenous epi-BL decreased GhGAI1 level in 7 dpa fiber.Similarly,the levels of the other three GhGAIs in 0 dpa ovules and 7 dpa fibers were also regulated by applied phytohormones.In addition,the levels of GhGAI1 were higher in Xuzhou142 fl mutant （fuzzless-lintless） than in FL （Gossypium hirsutum vs.Xuzhou 142） from-1 to 3 dpa ovules,suggesting that GhGAI1 engaged in cotton fiber cell initiation.These results indicated that DELLA genes are involved in the process of fiber cell initiation and elongation regulated by different phytohormones.