A nonlytic transforming mutant of herpes simplex virus type 2

Area of Science:

• Virology
• Molecular Biology
• Oncology

Background:

• Herpes simplex virus type 2 (HSV-2) strain 333 has a characterized small-plaque mutant (NO.69).
• This mutant produces a high ratio of noninfectious to infectious particles at nonpermissive temperatures.

Purpose of the Study:

• To demonstrate that noninfectious HSV-2 stocks retain transforming ability.
• To investigate the HSV gene responsible for thymidine kinase in a biochemical transformation assay.

Main Methods:

• Utilizing a biochemical transformation assay specific for the HSV thymidine kinase gene.
• Comparing DNA density and synthesis between the mutant and wild-type HSV-2.
• Analyzing virus and cell DNA synthesis post-infection at permissive and nonpermissive temperatures.

Main Results:

• Noninfectious HSV-2 stocks were successfully obtained while retaining transforming ability.
• The mutant's DNA genome density is identical to wild-type HSV-2.
• Virus and cell DNA synthesis were similar in cultures infected with the mutant or parental virus.

Conclusions:

• HSV-2 mutant NO.69 provides a tool for studying viral gene function, specifically thymidine kinase.
• Biochemically transformed mouse cells contain HSV antigens and are under investigation for oncogenic potential.
• This research advances the understanding of HSV-2 genetics and its implications in cellular transformation.