A captured viral interleukin 10 gene with cellular exon structure.
We have characterized a novel, captured and fully functional viral interleukin (IL)-10 homologue ((OvHV)IL-10) from the gammaherpesvirus ovine herpesvirus 2. Unlike IL-10 homologues from other gammaherpesviruses, the (OvHV)IL-10 peptide sequence was highly divergent from that of the host species. The (OvHV)IL-10 gene is unique amongst virus captured genes in that it has precisely retained the original cellular exon structure, having five exons of similar sizes to the cellular counterparts. However, the sizes of the introns are dramatically reduced. The (OvHV)IL-10 protein was shown to be a non-glycosylated, secreted protein of M(r) 21 000 with a signal peptidase cleavage site between amino acids 26 and 27 of the nascent peptide. Functional assays showed that (OvHV)IL-10, in a similar way to ovine IL-10, stimulated mast cell proliferation and inhibited macrophage inflammatory chemokine production. This is the first example of a captured herpesvirus gene retaining the full cellular gene structure.
Jayawardane
Gamini
G
Division of Medical Microbiology, School of Infection and Host Defence, University of Liverpool, Liverpool L69 3GA, UK.
Russell
George C
GC
Moredun Research Institute, Edinburgh EH16 0PZ, UK.
Thomson
Jackie
J
Moredun Research Institute, Edinburgh EH16 0PZ, UK.
Deane
David
D
Moredun Research Institute, Edinburgh EH16 0PZ, UK.
Cox
Helen
H
Division of Medical Microbiology, School of Infection and Host Defence, University of Liverpool, Liverpool L69 3GA, UK.
Gatherer
Derek
D
Medical Research Council Virology Unit, Institute of Virology, University of Glasgow, Glasgow G11 5JR, UK.
Ackermann
Mathias
M
Institute of Virology, University of Zurich, Zurich, Switzerland.
Haig
David M
DM
Moredun Research Institute, Edinburgh EH16 0PZ, UK.
Stewart
James P
JP
Division of Medical Microbiology, School of Infection and Host Defence, University of Liverpool, Liverpool L69 3GA, UK.
D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002460:Cell Line; D005091:Exons / Q000235:genetics*; D018142:Gammaherpesvirinae / Q000235:genetics*; D016753:Interleukin-10 / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D008407:Mast Cells / Q000276:immunology; D008969:Molecular Sequence Data; D011506:Proteins / Q000737:chemistry* / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012756:Sheep / Q000821:virology; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism
D011506:Proteins; D014764:Viral Proteins; D016753:Interleukin-10