The equine herpesvirus 1 UL45 homolog encodes a glycosylated type II transmembrane protein and is involved in virus egress.
Experiments to analyze the product of the equine herpesvirus type 1 (EHV-1) UL45 homolog were conducted. Using an antiserum generated against the carboxylterminal 114 amino acids of the EHV-1 UL45 protein, proteins of M(r) 32,000, 40,000, and 43,000 were detected specifically in EHV-1-infected cells. Neither form of the protein was located in purified virions of EHV-1 wild-type strain RacL22 or the modified live vaccine strain RacH, but UL45 was demonstrated to be expressed as a late (gamma-2) protein. Fractionation of infected cells and deglycosylation experiments demonstrated that the EHV-1 UL45 protein represents a type II membrane glycoprotein. Deletion of the UL45 gene in RacL22 and RacH (LDelta45 and HDelta45) showed that UL45 is nonessential for EHV-1 growth in vitro, but that deletion reduced the viruses' replication efficiency. A marked reduction of virus release was observed although no significant influence was noticed either on plaque size or on the syncytial phenotype of the EHV-1 strain RacH.
Oettler
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Institute for Medical Microbiology, Infectious and Epidemic Diseases, Ludwig-Maximilians-Universität München, Veterinärstr. 13, Munich, D-80539, Germany.
Kaaden
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OR
Neubauer
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A
D000818:Animals; D015139:Blotting, Southern; D015153:Blotting, Western; D002458:Cell Fractionation; D002460:Cell Line; D017353:Gene Deletion; D006031:Glycosylation; D004861:Herpesvirus 1, Equid / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D010948:Viral Plaque Assay; D014764:Viral Proteins; D014771:Virion / Q000378:metabolism; D019065:Virus Assembly
D008562:Membrane Glycoproteins; C088748:UL45 protein, herpes simplex virus type 1; D014759:Viral Envelope Proteins; D014764:Viral Proteins