A novel herpes simplex virus 1 gene, U(L)43.5, maps antisense to the U(L)43 gene and encodes a protein which colocalizes in nuclear structures with capsid proteins

An open reading frame mapping antisense to the U(L)43 gene of herpes simplex virus 1 encodes a protein with an apparent M(r) of 38,000, The protein was detected in wild-type-infected cells with rabbit monospecific polyclonal antibody directed against a fusion protein containing all of the sequences encoded by the open reading frame, The antibody did not react with mutants from,which the open reading frame was deleted, Expression of this gene, designated U(L)43.5, was grossly decreased or abolished in infected cells incubated in medium containing inhibitory concentrations of phosphonoacetic acid, suggesting that it is regulated as a gamma gene, U(L)43.5 is dispensable in cell culture, U(L)43.5 protein colocalized with the major capsid protein (infected cell protein 5) and the capsid scaffolding proteins (infected cell protein 35) in nuclear structures situated at the periphery of the nucleus, The predicted amino acid sequence indicates that the U(L)43.5 protein is a highly hydrophilic protein, The colocalization of U(L)43.5 protein with capsid proteins in discrete nuclear structures suggests that the former may be involved in assembly of viral particles in an accessory role in cells in culture.