title: Analysis of messenger RNA within virions of IBV.
abstract: The presence of subgenomic mRNAs (sgRNAs) in virions of infectious bronchitis virus was examined by probing Northern blots of RNA extracted from virions using as a probe a cDNA of the 3'-terminal nucleocapsid protein (N) gene. The sgRNAs were readily detected even after extensive purification of virions and after RNase A treatment of virions. The molar ratio of gRNA to each sgRNA was in the range 25 to 400 for IBV-M41 and 10 to 30 for IBV-Beaudette. After comparison with the molar ratios of genomic to intracellular viral sgRNAs it was estimated that the efficiency of incorporation of gRNA into virions was approximately 100 to 500-fold greater than for sgRNAs in the case of M41 and 20 to 100-fold for Beaudette, depending on the sgRNA species. It is concluded that sgRNAs can be present within IBV virions. Approximately 1 in 3 Beaudette virions and 1 in 20 M41 particles might contain a single copy of one sgRNA.
authors.affiliation: Division of Molecular Biology, AFRC Institute for Animal Health, Compton Laboratory, Newbury, UK.
authors.forename: D
authors.initials: D
authors.lastname: Cavanagh
authors.forename: K
authors.initials: K
authors.lastname: Shaw
authors.forename: X
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000818:Animals; D002213:Capsid / Q000235:genetics; D002642:Chick Embryo; D018076:DNA, Complementary / Q000235:genetics; D001351:Infectious bronchitis virus / Q000235:genetics* / Q000648:ultrastructure; D012367:RNA, Viral / Q000032:analysis*; D012259:Ribonuclease, Pancreatic / Q000378:metabolism; D014709:Vero Cells; D014758:Viral Core Proteins / Q000235:genetics; D014771:Virion / Q000737:chemistry*
chemical_list: D018076:DNA, Complementary; D012367:RNA, Viral; D014758:Viral Core Proteins; D012259:Ribonuclease, Pancreatic