Functional characterization of the HveA homolog specified by African greenmonkey kidney cells with a herpes simplex virus expressing the green fluorescence protein

We cloned the gene specified by African monkey kidney cells (Vero) that cod es for the homolog of the herpes virus entry mediator (HveA) specified by H eLa cells. The primary sequence of the monkey HveA (HveAs) differed signifi cantly from HveA. Single amino acid differences were distributed throughout the amino and carboxyl terminal portions of the HveAs in comparison with t he HveA, whereas certain regions were highly conserved. The predicted membr ane spanning domains of the two receptors differed substantially due to ins ertions and deletions of short amino acid sequences. The ability of HveAs t o mediate HSV virus entry was tested in a series of experiments using the r ecombinant virus KOS/EGFP, which constitutively expressed the enhanced gree n fluorescence protein (EGFP) and Chinese hamster ovary cells (CHO) transfo rmed with the HveAs gene. The KOS/EGFP virus was constructed by inserting a n EGFP gene cassette within the intergenic region between the UL53 (gK) and UL54 (ICP27) genes. The KOS/EGFP virus formed viral plaques and replicated as well as the wild-type KOS virus. HveAs-transformed CHO cells constituti vely expressing HveAs mediated herpesvirus entry efficiently whereas cells transformed with the HveAs gene in the noncoding orientation did not mediat e virus entry. A genetically engineered protein composed of the amino-termi nal portion of the HveAs protein fused to the heavy chain of mouse IgG immu noglobulin as well as mouse antibodies raised against HveAs blocked virus e ntry into HveAs-transformed CHO cells. Thus, HveAs is the functional homolo g of HveA, (C) 1999 Academic Press.