Sulphated glycoproteins induced by herpes simplex virus

Area of Science:

• Virology
• Molecular Biology
• Glycobiology

Background:

• Herpes simplex virus (HSV) infection involves complex viral protein synthesis.
• Viral glycoproteins play crucial roles in the HSV lifecycle and pathogenesis.
• Understanding post-translational modifications like sulfation is key to elucidating viral protein function.

Purpose of the Study:

• To identify and characterize sulfated polypeptides synthesized by HSV-infected cells.
• To determine which sulfated viral polypeptides are excreted from infected cells.
• To map the genomic location of sulfated glycoproteins.

Main Methods:

• Infection of Baby Hamster Kidney (BHK) cells with HSV-1 (strain 17 syn+) and HSV-2 (HG52).
• Metabolic labeling with inorganic sulfate.
• Analysis of radiolabeled polypeptides using SDS-polyacrylamide gel electrophoresis (SDS-PAGE).
• Immunological analysis to identify antigenically related polypeptides.
• Mapping of viral genes using intertypic recombinants.

Main Results:

• BHK cells infected with HSV incorporated inorganic sulfate into polypeptides that co-migrated with viral glycoproteins.
• Glycoprotein E was identified as the major sulfated glycoprotein.
• Sulfated bands were also observed co-migrating with glycoprotein D and HSV glycoprotein A/B/C.
• Major excreted sulfated polypeptides (32K, 34K, 35K) were antigenically related to glycoprotein D.
• Over 95% of the synthesized 32K, 34K, and 35K polypeptides were excreted.
• Glycoprotein E was mapped to a specific region (0.832-0.950) of the HSV genome.

Conclusions:

• HSV-1 and HSV-2 infected cells synthesize and incorporate sulfate into viral glycoproteins, notably glycoprotein E.
• Specific sulfated polypeptides, including those related to glycoprotein D, are significantly excreted from infected cells.
• The study provides insights into the post-translational modification and secretion of HSV glycoproteins, contributing to our understanding of HSV biology.