IDENTIFICATION OF GENE-PRODUCTS ENCODED BY THE LATENCY-RELATED GENE OF BOVINE HERPESVIRUS-1

Bovine herpesvirus 1 (BHV-1) establishes a latent infection in sensory ganglionic neurons of infected animals. Expression of latency-related (LR) gene products is controlled by a 980-bp fragment (LR promoter), DNA sequence analysis revealed that two major open reading frames (ORF s) are in the LR gene, Antibodies directed against both ORFs were gene rated in rabbits by using synthetic peptides. Antibody P2, which is di rected to sequences near the amino terminus of ORF 2, recognized a 41- kDa protein in lytically infected cells, suggesting that ORF 2 encodes a protein, When the LR gene was inserted into a mammalian expression vector and subsequently transfected into COS-7 cells, a 41-kDa protein was detected by use of silver-stained sodium dodecyl sulfate-polyacry lamide gels and by the P2 antibody, In contrast, this protein was not detected in mock-transfected cells, Deletion of DNA sequences containi ng ORF 2 blocked synthesis of the 41-kDa protein in COS-7 cells. Rever se transcriptase-mediated PCRs indicated that splicing occurs near the C terminus of ORF 2, Further studies indicated that LR RNA was altern atively spliced in latently infected cattle and that a fraction of LR RNA was poly(A)(+). Taken together, these studies suggested that a spl iced LR transcript has the potential to encode a 41-kDa protein.