重组HIV-1壳体蛋白在转基因枸杞根系中的分泌表达

P24壳体蛋白（capsid, CA）是HIV¬-1早期感染的一个重要标志.用含有植物表达载体pCAMBIA 1305.2- MA4-CA（包含GRP信号肽和MA4-CA融合基因）的农杆菌菌株侵染枸杞,将转有MA4-CA融合基因的转化株诱导生根，并进行毛状根的培养; western blot证实根系及培养液中的MA4-CA融合蛋白以二聚体的形式存在，分子量为50 kDa；免疫组织化学显示，CA定位在细胞浆、细胞壁和细胞间隙中，充分证实了利用GRP信号肽可以引导重组蛋白分泌表达。建立枸杞中HIV-1壳体蛋白的根分泌表达系统，为研究植物HIV-1 CA-病毒样颗粒（VLPs）疫苗奠定基础。

Rhizosecretion of HIV-1 recombinant capsid protein from transgenic Lycium barbarum L. hairy roots

HIV p24 core protein can induce both cellular and neutralizing antibody responses.HIV-1 CA-virus-like particles(VLPs)vaccines provide a promising approach for the development of an effective vaccination strategy against HIV infection.Rhizosecreion of the recombinant proteins provides a new manufacturing platform that can simplify the extraction and purification procedure.Lycium barbarum L.was transformed by Agrobacterium tumefaciens EHA105 harboring the plant expression vector pCAMBIA1305.2-MA4-CA with a GRP signal peptide and MA4-CA fusion gene.Transgenic hairy roots were induced and cultivated in hydroponic culture.Western blotting indicated that the recombinant CA proteins were present in two forms,a glycosylated monomer(37 kDa)and a dimer(50 kDa)in the roots and hydroponic medium.It appeared from the present immunohistochemical data that the recombinant CA proteins fused with GRP signal peptide were confined to the cytoplasm,cell wall and intercellular space,indicating targeting into the secretory pathway.It demonstrated for the first time the rhizosecretion of HIV-1 recombinant capsid protein in Lycium barbarum L.hairy roots,and may offer a novel method for expressing HIV-1 CA-VLPs vaccines in plants.