摘要
[目的]死皮是指橡胶树(Hevea brasiliensis)产排胶过程中出现的一种割线症状,它会造成橡胶减产甚至完全绝收。研究对一死皮相关的水通道蛋白(Aquaporin,AQP)基因进行克隆和序列分析,以探讨AQP在死皮发生过程中的作用。[方法]基于一条在死皮植株中下调表达的EST,研究采用电子克隆和RT-PCR相结合的方法从橡胶树的树皮中扩增出HbTIP1 774 bp的cDNA,在此基础上采用生物信息学对基因的序列特征、编码蛋白的理化特性及进化关系进行了分析。[结果]该cDNA包含759 bp的ORF、8 bp的5’UTR和7 bp的3’UTR;基因预测编码252个氨基酸,理论分子量为25.88 kD,等电点为4.96。生物信息学分析显示,HbTIP1含有1个保守的MIP结构域,6个跨膜螺旋,液泡膜定位,可归为水通道蛋白(Aquaporin,AQP)家族TIP亚族。同源分析显示,HbTIP1与可可(Theobroma cacao)、人参(Prunus persica)、橙子(Citrus sinensis)和蓖麻(Ricinus communis)中同源蛋白的相似性都在90%以上,显示出高度的保守性。[结论]该研究为下一步揭示AQP调控死皮发生机制创造了条件。
[Objective] To address the role of aquaporins （AQPs） in the occurrence of Tapping Panel Dryness （TPD）,a syndrome with tapping incision blocked partly or entirely during latex exploiting in the rubber tree （Hevea brasiliensis） that causes great losses on rubber production,a tonoplast aquaporin gene associated with TPD occurence was cloned and analyzed.[Methed] Based on a EST down-regulated in the TPD-affected rubber trees,a 774 bp cDNA designated HbTIP1 was isolated from the bark tissue of rubber tree with a combination of in silico cloning and RTPCR.Furthermore,the sequence features of HbTIP1,the biochemical features of its deduced protein and the evolutionary relationship were also analyzed via bioinformatics tools.[Result]The cDNA contains a 759 bp long ORF,8 bp 5＇UTR and 7 bp 3＇UTR.Sequence analysis indicated that HbTIP1 encodes 252 amino acids with a theoretical molecular weight （Mw） of 25.88 kDa and isolectric point （pI） of 4.96.Bioinformatics analysis suggested the deduced protein is predicted to have six transmembrane helices located to the vacuolar membrane,and harbeur one MIP domain that can be grouped into the tonoplast intrinsic proteins （TIPs） of Aquaporin family.Homology search revealed that the protein shares a similarity of more than 90％ with the homologues in Theobroma cacao,Prunus persica,Citrus sinensis and Ricinus communis,supportting a highly conserved evolution.[Conclusion] This study provided a basis for uncovering the regulatory role of AQPs in TPD occurrence in the future.
出处
《安徽农业科学》
CAS
2013年第36期13851-13854,共4页
Journal of Anhui Agricultural Sciences
基金
国家自然科学基金(31371556)
海南省自然科学基金(312026)
中国热带农业科学院橡胶研究所基本科研业务费专项(1630022011014)
关键词
橡胶树
死皮
水通道蛋白
Hevea brasiliensis
Tapping panel dryness
Aquaporin
