Comparison of a 20 kb region of human herpesvirus 6B with other human betaherpesviruses reveals conserved replication genes and adjacent divergent open reading frames

• Published in: Archives of virology Vol. 142; no. 1; pp. 193 - 204
• Main Authors: Lindquester, G. J, Greenamoyer, C. A, Anton, E. D, O’Brian, J. J, Pellett, P. E, Dambaugh, T. R
• Format: Journal Article
• Language: English
• Published: Wien Springer-Verlag 1997; New York, NY Springer
• Subjects: amino acid sequences; Biological and medical sciences; DNA replication; evolution; exons; Fundamental and applied biological sciences. Psychology; genes; Genetics; glycoproteins; Human herpesvirus 5; Human herpesvirus 6; humans; loci; metabolism; Microbiology; open reading frames; Virology; viruses; Virus; Herpesvirus hominis 6; Genetic variability; Taxonomy; Herpesviridae; DNA; Biological evolution; Phylogeny
• ISSN: 0304-8608; 1432-8798
• DOI: 10.1007/s007050050070

The sequence of a 20.15 kb region from human herpesvirus 6 variant B (HHV-6B) strain Z29 is described (GenBank accession number L14772). Determinations of protein homologies for seventeen predicted gene products revealed HHV-6B homologs of six proteins well-conserved both in genetic context and amino acid sequence throughout the alpha-, beta-, and gammaherpesvirus subfamilies. These include proteins involved in viral DNA replication, packaging and nucleotide metabolism, and conserved proteins of undefined function. The close evolutionary relationship of the human betaherpesviruses, HHV-6B, HHV-6A, HHV-7 and human cytomegalovirus (HCMV) was confirmed by identification of several protein sequences encoded only by these viruses, including homologs of the HCMV early phosphoprotein family and a series of HCMV open reading frames predicted to encode glycoprotein exons. Homologs of essential HSV-1 replication proteins, UL8 and UL9, were also identified. Downstream from the conserved replication locus, each betaherpesvirus contains a region of divergent, small open reading frames. The evolution of this region and its potential use in the development of a viral vector system are discussed.