橡胶树水通道蛋白基因HbPIP1;2和HbPIP2;2的克隆及序列分析

Molecular Cloning and Sequence Analysis of HbPIP1;2 and HbPIP2;2 Aquaporin Genes in Hevea brasiliensis

根据GenBank中已经公布的不同植物水通道蛋白(AQPs)的保守氨基酸序列设计简并引物,结合RT-PCR和RACE技术,从橡胶树(Hevea brasiliensis)中克隆了2个AQP基因的全长cDNA序列,并对其进行生物信息学分析。结果获得橡胶树2个AQPs基因的全长,分别命名为HbPIP1;2和HbPIP2;2。HbPIP1;2编码273个氨基酸,理论分子量为29.15kD,等电点为8.55;HbPIP2;2编码278个氨基酸,理论分子量为29.78kD,等电点为8.20。HbPIP1;2和HbPIP2;2均具有6个跨膜区和MIP家族信号序列SGXHXNPAVT,为疏水性蛋白;HbPIP1;2和HbPIP2;2与同科蓖麻水通道蛋白基因RcPIP1-3和RcPIP2-1的同源性分别为91%和89%,并具有相同功能域。因此,推测Hb-PIP1;2和HbPIP2;2都属于水通道蛋白基因家族的新成员。

Degenerate primers were designed based on the conserved amino acid sequence of the published AQPs from different plant species, the method of RT-PCR and RACE were adopted and two full-length cDNAs encoding aquaporins were cloned from the bark of Hevea brasiliensis. Bioinformatics tools were applied to analyze both the cDNA sequence and protein sequence. Two AQP genes were obtained from H. brasiliensis, which were designated HbPIP1;2 and HbPIP2;2. The HbPIP1;2 encoding 273 amino acids with molecular weight 29. 15 kD and theoretical pI 8. 55; and the HbPIP2 ;2 encoding 278 amino acids with molecular weight 29.78 kD and theoretical pI 8.20; HDPIP1;2 and HDPIP2;2 both contain six transmembrane areas, possessing the MIP family signal consensus sequence SGXHXNPAVT, and were predicted as hydrophobic protein. The HbPIP1; 2 and Ht）PIP2 ; 2 had 91 % and 89 % homology with the published aquaporin genes of the Ricinus communis plasma membrane intrinsic protein by the nucleic acid and amino acid sequence homology analysis, so the HbPIP1 ;2 and HbPIP2 ;2 both belong to new member of aquaporins family.