橡胶树线粒体解偶联蛋白HbUCP5基因的克隆与表达分析  

Cloning and Expression Analysis of Mitochondrial Uncoupling Protein Gene HbUCP5 in Rubber Tree

作　　者：杨洪[1] 刘明洋 代龙军[1] 郭冰冰 王立丰[1] Yang Hong;Liu Mingyang;Dai Longjun;Guo Bingbing;Wang Lifeng(Key Laboratory of Materials Engineering for High-Performance Natural Rubber,State Key Laboratory Incubation Base for Cultivation&Physiology of Tropical Crops,Danzhou Investigation&Experiment Station of Tropical Crops(Ministry of Agriculture and Rural Affairs),Key Laboratory of Biology and Genetic Resources of Rubber Tree(Ministry of Agriculture and Rural Affairs),Rubber Research Institute,Chinese Academy of Tropical Agricultural Sciences,Haikou,571101)

机构地区：[1]中国热带农业科学院橡胶研究所,农业农村部橡胶树生物学与遗传资源利用重点实验室,农业农村部儋州热带作物科学观测实验站,省部共建国家重点实验室培育基地-海南省热带作物栽培生理学重点实验室,海南省高性能天然橡胶材料工程重点实验室,海口571101

出　　处：《分子植物育种》2023年第16期5255-5264,共10页Molecular Plant Breeding

基　　金：海南省自然科学基金项目(320QN350);海南省自然科学基金创新研究团队项目(321CXTD445);中国热带农业科学院基本科研业务费专项(1630022020015)共同资助。

摘　　要：线粒体解耦联蛋白(mitochondrial uncoupling protein,UCP)是位于线粒体内膜上的特殊蛋白,广泛参与生物产热调节和抗氧化防御。为了研究线粒体解耦联蛋白基因在橡胶树中的功能,本研究克隆了巴西橡胶树线粒体解偶联蛋白基因Hb UCP5,对该基因及其编码蛋白进行生物信息学分析,并探究其在橡胶树中的表达模式。研究结果表明巴西橡胶树中HbUCP5基因cDNA序列开放阅读框(ORF)长978 bp,编码325个氨基酸。HbUCP5相对分子量和理论等电点分别为34.72 kD和9.89,是一个疏水的稳定蛋白。HbUCP5有多个磷酸化位点和O-糖基化位点,无信号肽,定位于线粒体。HbUCP5二级结构主要由α-螺旋、β-转角、延伸链和不规则卷曲构成,其中α-螺旋和无规则卷曲占比最高,分别为44%和36%。系统进化分析表明,HbUCP5与其他植物UCP5亚族共同聚为Group IV分支。表达模式分析结果表明,HbUCP5在花、乳管、茎尖等代谢旺盛组织和叶片生长旺盛时期高表达,乙烯利诱导HbUCP5表达,而死皮树中HbUCP5表达下调,排胶顺畅橡胶树品系中显著高表达。HbUCP5在幼嫩及代谢活跃组织中高表达且其表达受乙烯利诱导,推测HbUCP5参与橡胶树细胞代谢过程能量供给及乙烯诱导的氧化还原平衡调控。该基因在不同排胶状态树中的表达模式表明HbUCP5可能通过调节排胶过程活性氧(reactive oxygen species,ROS)平衡参与橡胶树产排胶。Mitochondrial uncoupling proteins(UCPs)are specialized proteins in the inner membrane that have been implicated in several cellular functions ranging from thermoregulation to antioxidant defense.In order to study the function of UCPs in Hevea brasiliensis,the HbUCP5 was cloned,and the bioinformatics analysis of the gene and its encoded protein was carried out,the expression pattern of HbUCP5 in rubber trees was further analyzed in this study.The results showed that the open reading frame(ORF)of HbUCP5 was 978 bp in length,encoding 325 amino acids.The protein encoded by HbUCP5 was a hydrophobic and stable protein with molecular weight and theoretical isoelectric points of 34.72 kD and 9.89,respectively.The HbUCP5 protein has no signal peptide except for multiple phosphorylation sites and O-glycosylation sites and is most likely localized in the mitochondria in subcellular localization analysis.The secondary structure of HbUCP5 mainly consists ofα-helix,β-turn,extended chain,and random coils,among whichα-helix and random coils account for the highest percentage of 44%and 36%,respectively.Phylogenetic analysis showed that HbUCP5 clustered into Group IV with other plant UCP5 subgroup.Expression pattern analysis showed that HbUCP5 was highly expressed in vigorous and metabolically active tissues such as flowers,laticifer,stem,and young leaves.The expression of HbUCP5 was induced by ethylene,while inhibited by tapping panel dryness.Furthermore,HbUCP5 was also up-regulated in the clone with a longer latex flow duration.while HbUCP5 was highly expressed in young and metabolically active tissues.In addition,its expression was also induced by the latex yield stimulator ethephon,we hypothesize that HbUCP5 is involved in the regulation of energy supply and redox homeostasis during the metabolism of rubber tree cells.Taken together,our results indicate that HbUCP5 may involve in latex flow by controlling ROS balance during the metabolic process of rubber tree cells.

关 键 词：橡胶树 线粒体 解偶联蛋白 基因克隆 基因表达分析 

分 类 号：S794.1[农业科学—林木遗传育种]