Analysis Of The Biological Role Of The Herpes Simplex Virus Type ? VP26 Protein As Its Infection

Herpes simplex virus I (HSV-1) is an enveloped double-stranded DNA virus which infection is ubiquitous, and exhibits complicated interactions with host cells during virus infection. The interactions between HSV-1 and infected cells provided the basis for study of viral infection processes and results in different infected cells.The point of this reseach is to analysis the role of VP26 and its function of interacting with the cellular membrane tetraspanin 7 protein (CMTP-7) at HSV-1 egress in viral infection cycle. No definitive function has been ascribed to HSV-1 VP26.A recombinant virus encoding the GFP fused to the UL35 gene was constructed for these studies. The titre of UL35-EGFP recombinant virus was investigated. The wild strain showed a rapid increase in virus titre while recombinant virus induced a more slow-rising increase in virus titre because of intracytoplasmic aggregates forming in the miopragia of VP26. Our evidence suggested that VP26 protein is involved in the process of virus egress from the cell membrane.In yeast two-hybrid system, the protein interaction with VP26 was analyzed, one of positive clones from human embryo kidney cDNA library was identified as cellular membrane tetraspanin 7 protein. The interaction between VP26 and tetraspanin 7 was confirmed in L-02 cells by co-immunoprecipitation assay.The infected cells were detected by flow cytometry, results show CMTP-7 was decrease following with virus egress from the plasma membrane. The amount of virus increase slowly and intracytoplasmic aggregates formation are located typically near the plasmic membrane of which CMTP-7 is interfered cells, similar to the UL35-EGFP recombinant virus in infected cell.These findings suggest the interacting between VP26 and CMTP-7 protiens can be used to trigger envelope generators, meanwhile it was involved in egress from the host-cell and represent components of mature virions.A hypothesis model of herpes simplex virus egress from infected cells is developed. Based above evidences, capsids cross nuclear membranes by envelopment at the inner nuclear membrane followed by fusion or deenvelopment at the outer nuclear membrane, delivering nucleocapsids into the cytoplasm. Secondary envelopment occurs as herpesvirus capsids bind onto the plasma membrane via the interaction of VP26 with CMTP-7 protiens and this enveloped virions egress from the host-cell.