title: Genomic regions associated with neurotropism identified in MHV by RNA-RNA recombination.
abstract: Infection of mice with a neurotropic strain of MHV (MHV-A59), a non-neurotropic strain of MHV (MHV-2), and a set of recombinant viruses (kindly provided by Dr. Michael Lai) were used to map genetic determinants of viral neurotropism and demyelination. Following intracerebral (IC) inoculation of 4-week old C57B1/6 mice, 1LD50 of MHV-A59 produced acute meningoencephalitis and hepatitis, and subsequently chronic CNS demyelinating disease. IC inoculation of 1LD50 of MHV-2 produced acute hepatitis without CNS disease. Recombinants ML-3, ML-11, ML-7, ML-8, ML-9 and ML-10 produced acute encephalitis similar to MHV-A59. According to previous oligonucleotide fingerprinting analysis the only common denominator of the neurotropic recombinant viruses was an M gene derived from MHV-A59. Sequencing of PCR-amplified viral S and M genes confirmed that the M genes of neurotropic viruses are derived from A59 while the S genes of neurotropic viruses are either derived from MHV-2 or from A59. In tissue culture, ML-11, ML-3 and MHV-2 are fusion negative, while A59, ML-7, ML-8 and ML-10 are fusion positive. Thus, neurotropism in MHVs is not linked to fusion or the S gene. Moreover, the M gene may be a significant determinant of neurotropism and acute encephalitis.
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia 19104-6079, USA.
authors.forename: E
authors.initials: E
authors.lastname: Lavi
authors.forename: Q
authors.initials: Q
authors.lastname: Wang
authors.forename: S T
authors.initials: ST
authors.lastname: Hingley
authors.forename: S R
authors.initials: SR
authors.lastname: Weiss
mesh_terms: D000818:Animals; D001921:Brain / Q000473:pathology / Q000821:virology*; D018352:Coronavirus Infections / Q000473:pathology / Q000503:physiopathology* / Q000821:virology; D016679:Genome, Viral; D051379:Mice; D008810:Mice, Inbred C57BL; D006517:Murine hepatitis virus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity*; D009928:Organ Specificity; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D011995:Recombination, Genetic; D013045:Species Specificity; D014763:Viral Matrix Proteins / Q000096:biosynthesis / Q000235:genetics; D014774:Virulence
chemical_list: D012367:RNA, Viral; D014763:Viral Matrix Proteins