title: Recovery of avian metapneumovirus subgroup C from cDNA: cross-recognition of avian and human metapneumovirus support proteins.
abstract: Avian metapneumovirus (AMPV) causes an acute respiratory disease in turkeys and is associated with "swollen head syndrome" in chickens, contributing to significant economic losses for the U.S. poultry industry. With a long-term goal of developing a better vaccine for controlling AMPV in the United States, we established a reverse genetics system to produce infectious AMPV of subgroup C entirely from cDNA. A cDNA clone encoding the entire 14,150-nucleotide genome of AMPV subgroup C strain Colorado (AMPV/CO) was generated by assembling five cDNA fragments between the T7 RNA polymerase promoter and the autocatalytic hepatitis delta virus ribozyme of a transcription plasmid, pBR 322. Transfection of this plasmid, along with the expression plasmids encoding the N, P, M2-1, and L proteins of AMPV/CO, into cells stably expressing T7 RNA polymerase resulted in the recovery of infectious AMPV/CO. Characterization of the recombinant AMPV/CO showed that its growth properties in tissue culture were similar to those of the parental virus. The potential of AMPV/CO to serve as a viral vector was also assessed by generating another recombinant virus, rAMPV/CO-GFP, that expressed the enhanced green fluorescent protein (GFP) as a foreign protein. Interestingly, GFP-expressing AMPV and GFP-expressing human metapneumovirus (HMPV) could be recovered using the support plasmids of either virus, denoting that the genome promoters are conserved between the two metapneumoviruses and can be cross-recognized by the polymerase complex proteins of either virus. These results indicate a close functional relationship between AMPV/CO and HMPV.
authors.affiliation: Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA.
authors.forename: Dhanasekaran
authors.initials: D
authors.lastname: Govindarajan
authors.forename: Ursula J
authors.initials: UJ
authors.lastname: Buchholz
authors.forename: Siba K
authors.initials: SK
authors.lastname: Samal
mesh_terms: D000818:Animals; D001717:Birds; D003001:Cloning, Molecular / Q000379:methods; D003429:Cross Reactions; D018076:DNA, Complementary; D005822:Genetic Vectors; D016679:Genome, Viral; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D029121:Metapneumovirus / Q000235:genetics*; D018184:Paramyxoviridae Infections; D010957:Plasmids; D018099:Pneumovirinae / Q000235:genetics*; D014765:Viral Vaccines
chemical_list: D018076:DNA, Complementary; D014765:Viral Vaccines; D049452:Green Fluorescent Proteins