巴西橡胶树赤霉素信号转导途径HbRGA1结构和功能分析

Structural and Functional Analysis of Gibberellin Signaling Transduction Pathway Gene HbRGA1 in Rubber Tree

DELLA蛋白是赤霉素激素信号负调控因子,具有抑制植物生长发育的作用。解析其家族成员结构与功能将有助于揭示橡胶树DELLA蛋白家族成员调控橡胶树生长发育的机制。本研究从橡胶树热研73397叶片中克隆HbRGA1的cDNA全长序列。该基因长为2136 bp,含1839 bp的ORF,编码613个氨基酸。HbRGA1蛋白序列包含DELLA和GRAS保守结构域,与杨树、木薯和橡胶树DELLA基因相似性高达82.5%。qRT-PCR分析发现HbRGA1在橡胶树叶片中表达量高,在树皮和胶乳中表达量极低。叶片中HbRGA1表达量受喷施赤霉素和脱落酸等诱导显著上调。本研究表明HbRGA1与橡胶树赤霉素等激素信号密切相关,为深入研究其在橡胶树生长发育中的结构和功能打下良好基础。

DELLA protein is a negative regulator of gibberellin signaling pathway,which inhibits plant growth and development.Analyzing the structure and function of DELLA family members will be helpful to elucidate the mechanism by which the DELLA protein regulates the growth and development of rubber trees.In this study,the full-length cDNA sequence of HbRGA1 was cloned from the leaves of rubber tree cultivar Reyan73397.HbRGA1 is 2136 bp long,contains 1839 bp ORF,and encodes 613 amino acids.The HbRGA1 protein sequence contains DELLA and GRAS superfamily conserved domains,which are 82.5%like the DELLA genes of poplar,cassava and rubber trees.qRT-PCR analysis showed that the expression level of HbRGA1 was high in the leaf of rubber tree,but very low in the bark and latex.The expression of HbRGA1 in leaves was significantly up-regulated by gibberellin and abscisic acid spraying.These results indicated that HbRGA1 was closely related to gibberellin and other hormone signals in rubber trees,which laid a good foundation for further study of HbRGA1’s structure and function in the growth and development of rubber trees.