Localization of the antigenic sites and intrinsic protein kinase domain within a 300 amino acid segment of the ribonucleotide reductase large subunit from herpes simplex virus type 2

• Published in: Virology (New York, N.Y.) Vol. 187; no. 1; pp. 360 - 367
• Main Authors: Ali, Mir A., Prakash, S.S., Jariwalla, Raxit J.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.03.1992; Elsevier
• Subjects: Base Sequence; Biological and medical sciences; Cloning, Molecular; Epitopes - genetics; Epitopes - immunology; Fundamental and applied biological sciences. Psychology; herpes simplex virus 2; Microbiology; Microscopy, Fluorescence; Molecular Sequence Data; Morphology, structure, chemical composition, physicochemical properties; Mutagenesis, Site-Directed; Protein Kinases - genetics; Protein Kinases - immunology; Restriction Mapping; Ribonucleotide Reductases - genetics; Ribonucleotide Reductases - immunology; Simplexvirus - enzymology; Simplexvirus - genetics; Simplexvirus - immunology; Virology; Virus; Ribonucleotide reductase; Enzymatic activity; Antigenic determinant; Structure activity relation; Enzyme; Herpesvirus hominis 2; Protein kinase; Herpesviridae; Alphaherpesvirinae; Monoclonal antibody; Subunit
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1016/0042-6822(92)90328-M

The 140-kDa ribonucleotide reductase (RR1) protein of herpes simplex virus type 2 (HSV-2) functions as the large subunit of virus-specified RR1 and exhibits an intrinsic protein kinase (PK) activity at its unique NH 2 terminal region. The N-terminal half of RR1 contains the protein and DNA functions of the morphological transforming region III ( mtrIII) of HSV-2. In the present study, we have expressed a number of truncated RRi derivatives in a mammalian expression vector containing NH 2 terminal RR1 gene fragments and amber mutants generated by site-specific mutagenesis. These derivatives, synthesized in transient expression assays, were used as test antigens to localize the epitopes of a panel of HSV-2 RR1-reactive monoclonal antibodies and to fine-map the PK catalytic domain. Our data show that the epitope for HSV-2-specific monoclonal antibody 6A-6 is located in a region of RR1 protein spanning as 72–350. The epitopes for cross-reactive antibodies to HSV RR1, i.e., 48S and 51 S, are formed predominantly by a stretch of amino acid residues specified by as 350–376 of the RRI molecule. The 6A-6 antibody utilized in conjunction with the RR1 amber mutants has allowed us to define a 278 as domain within the NH2 terminal half of the 140-kDa RR1 (aa 72–350) that is sufficient for PK activity.