title: Nucleotide sequence and construction of an infectious cDNA clone of an EMCV strain isolated from aborted swine fetus.
abstract: A full-length cDNA clone of an Encephalomyocarditis virus (EMCV) strain (2887A) isolated from aborted swine fetus was constructed and sequenced. Sequence comparison showed more than 99% nucleotide and amino acid sequence identity with two other EMCV strains, EMCV-PV21 and -R. However, the 2887A genomic sequence showed only about 84% nucleotide identity and 96% amino acid identity with EMCV-B, -D and -PV2 variants. RNA synthesized by in vitro transcription of this cDNA clone was infectious upon transfection of BHK21 cells, as shown by cytopathic effects and identification by neutralization test, and by propagation of the virus released into the culture media. The transcript RNA led to the production of infectious particles despite the presence of two nongenomic nucleotide residues at the 5' end, the short poly(C) tract (C(10)TCTC(3)TC(10)), the short poly(A) tail (7A), and the presence of six nongenomic nucleotides at the 3' end. The rescued virus was also found to be highly pathogenic for mice by intra-peritoneal inoculation producing a fatal disease indistinguishable from that of wild-type virus. An important finding concerning the molecular basis of infectivity was that the in vitro synthesized EMCV RNA transcript is infectious, although it contains a very short poly(A). The availability of the infectious cDNA clone of the reproductive failure strain of EMCV should prove to be useful for studying the molecular basis of the pathogenicity of EMCV in pig.
authors.affiliation: Agence Française de Sécurité Sanitaire des Aliments, AFSSA-Alfort, 22 rue Pierre Curie BP 67, 94703 Maisons-Alfort Cedex, France. l.bakkali@afssa.fr
authors.forename: Labib Bakkali
authors.initials: LB
authors.lastname: Kassimi
authors.forename: Annie
authors.initials: A
authors.lastname: Boutrouille
authors.forename: Monique
authors.initials: M
authors.lastname: Gonzague
authors.forename: Anicet Lipobo
authors.initials: AL
authors.lastname: Mbanda
authors.forename: Catherine
authors.initials: C
authors.lastname: Cruciere
mesh_terms: D000031:Abortion, Septic / Q000662:veterinary / Q000821:virology; D000034:Abortion, Veterinary / Q000821:virology*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018188:Cardiovirus Infections / Q000821:virology*; D003001:Cloning, Molecular; D006224:Cricetinae; D018076:DNA, Complementary; D004686:Encephalomyocarditis virus / Q000235:genetics* / Q000302:isolation & purification; D005260:Female; D016679:Genome, Viral; D008969:Molecular Sequence Data; D009711:Nucleotides; D011247:Pregnancy; D011270:Pregnancy, Animal; D017422:Sequence Analysis, DNA; D013552:Swine; D014158:Transcription, Genetic; D014162:Transfection
chemical_list: D018076:DNA, Complementary; D009711:Nucleotides