Some highlights of virus research in 1988.

Our review of the highlights in virus research in 1988 differs from the previous highlight reviews (McGeoch et al., 1986, 1987, 1988c) in that it includes work on plant viruses as well as animal viruses. This change is an attempt to make these reviews more general and to indicate areas of similarity and contact between the viruses of different kingdoms. Nonetheless it remains a highly selective view of progress in a wide and expanding scientific field. We start by describing the current work on three specific groups of viruses, herpesviruses, hepadnaviruses and hepatitis delta virus (HDV). This leads into a discussion of mechanisms by which viral genes are replicated and expressed and then into some recent findings on viral genome organization, virus structure, the use of transformation in the study of plant viruses, and we conclude with an account of new disease agents. For the first time we do not have a section devoted to AIDS and human immunodeficiency virus (HIV); this reflects both the selective nature of our account, and also an evaluation that HIV research has now emerged from its initial phase of rapid discovery, so that truly notable advances are becoming less frequent, despite the very large efforts being made. In 1988 determination of the DNA sequence of herpes simplex virus type 1 (HSV-1) was completed (McGeoch et al., 1988a; Perry & McGeoch, 1988). The sequence contains 152260 residues of overall base composition 68.3~ G + C. This is the third herpesvirus sequence to be published, after those for Epstein-Barr virus (EBV) and varicella-zoster virus (VZV). The HSV-1 sequence appears to contain at least 72 genes. At present there is no significant information on function for approximately half of these. During 1987 and 1988, results were published concerning transcription of HSV DNA in latently infected neurons. It has been found, for both experimental and natural infections, that in these neurons transcripts originate largely from the long repeat element of the genome (Rock Their 5' termini are from a region without any assigned protein-coding function (the largest such region in the genome) and their 3' portions overlap partially, in the opposing sense, with one of the immediate early (IE) genes, which encodes a transcriptional regulator (IE 110 or ICP0). These latency-associated transcripts (LATs) are up to about 2 kb, include spliced species and are not polyadenylated. While there is great interest in LATs as a possible mechanism in …