Comparison of a 20 kb region of human herpesvirus 6B with other human beta herpesviruses reveals conserved replication genes and adjacent divergent open reading frames.
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.
Lindquester
G J
GJ
Department of Biology, Rhodes College, Memphis, Tennessee, USA.
Greenamoyer
C A
CA
Anton
E D
ED
O'Brian
J J
JJ
Pellett
P E
PE
Dambaugh
T R
TR
D017124:Conserved Sequence; D019143:Evolution, Molecular; D005814:Genes, Viral; D016679:Genome, Viral; D015654:Herpesvirus 6, Human / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics*; D017421:Sequence Analysis