巴西橡胶树胶乳中DUF1262结构域蛋白结构与基因表达分析

Structural and Gene Expression Analysis of a DUF1262 Domain Protein in Latex from Hevea brasiliensis

为了揭示天然橡胶生物合成酶互作蛋白结构及其在天然橡胶生物合成过程中的功能。本研究以橡胶树胶乳橡胶粒子总蛋白为研究对象,采用免疫共沉淀实验技术以天然橡胶合成关键酶顺式-异戊二烯基转移酶(CPT)抗体从胶乳中捕获了1个含DUF1262结构域的未知功能蛋白。生物信息学分析表明橡胶树基因组中包含50个编码含DUF1262结构域蛋白的基因序列;蛋白质相互作用网络分析表明DUF1262结构域蛋白可能参与调节信号转导或转录调控等过程;荧光定量PCR结果表明编码该蛋白基因的转录本在根、叶、花、枝和胶乳等组织中广泛分布,但在胶乳中表达较低,在树皮表达较高;水杨酸、脱落酸、过氧化氢及干旱处理可增强该基因在叶片中的转录水平。本研究证明DUF1262参与橡胶树逆境反应等生理过程,为揭示胶乳生物合成调控机制提供新线索。

To reveal the structure and function of natural rubber biosynthase interacting proteins in natural rubber biosynthesis,the total protein of latex rubber particles of Hevea brasiliensis was used as material,and an unknown functional protein containing DUF1262 domain was captured by immunoprecipitation assay using an antibody targeting CPT,a key enzyme for natural rubber biosynthesis.Bioinformatics analysis showed that there were 50 gene sequences encoding DUF1262 domain proteins in the rubber tree genome,and protein interaction network analysis suggested that DUF1262 domain proteins might be involved in signal transduction and transcriptional regulation.Fluorescence quantitative PCR results showed that the transcription of the gene encoding this protein was widely distributed in roots,leaves,flowers,branches,latex and other tissues respectively,andthe expression was low in latex and but high in bark.Salicylic acid,abscisic acid,hydrogen peroxide and drought treatment could enhance the transcription level of this gene in leaves respectively.This study demonstrated that the DUF1262 protein was involved in stress response and other physiological processes of rubber tree,providing new clues for revealing the regulation mechanism of latex biosynthesis.