Herpesvirus Thymidine Kinase (Herpes_TK)

Herpesvirus thymidine kinase (TK) is a viral enzyme encoded by members of the Herpesviridae family. It catalyzes the phosphorylation of thymidine to thymidine monophosphate (dTMP), a key step in the pyrimidine salvage pathway necessary for viral DNA replication. It's a target for antiviral drugs and used in suicide gene therapy. Its presence in herpesvirus-infected cells is used to activate a range of antivirals against herpes infection, specifically targeting therapy towards infected cells only. HSV [thymidine kinase] has been widely investigated for use in suicide gene therapy. When treated with non-toxic prodrug [like GCV], drug is converted into its toxic form only in [targeted] tumor cells.

Phosphorylation of nucleoside analogs into active antiviral metabolites, selective killing of HSV-TK expressing cells