Molecular characterization of infectious clones of the minute virus of canines reveals unique features of bocaviruses.
Minute virus of canines (MVC) is a member of the genus Bocavirus in the family Parvoviridae. We have molecularly cloned and sequenced the 5'- and 3'-terminal palindromes of MVC. The MVC genome, 5,404 nucleotides (nt) in length, shared an identity of 52.6% and 52.1% with that of human bocavirus and bovine parvovirus, respectively. It had distinct palindromic hairpins of 183 nt and 198 nt at the left-end and right-end termini of the genome, respectively. The left-end terminus was also found in two alternative orientations (flip or flop). Both termini shared extensive similarities with those of bovine parvovirus. Four full-length molecular clones constructed with different orientations of the left-end terminus proved to be infectious in Walter Reed canine cell/3873D (WRD) canine cells. Both MVC infection and transfection of the infectious clone in WRD cells revealed an identical RNA transcription profile that was similar to that of bovine parvovirus. Mutagenesis of the infectious clone demonstrated that the middle open reading frame encodes the NP1 protein. This protein, unique to the genus Bocavirus, was essential for MVC DNA replication. Moreover, the phospholipase A2 motif in the VP1 unique region was also critical for MVC infection. Thus, our studies revealed important information about the genus Bocavirus that may eventually help us to clone the human bocavirus and study its pathogenesis.
Sun
Yuning
Y
Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Mail Stop 3029, 3901 Rainbow Blvd., Kansas City, KS 66160, USA.
Chen
Aaron Yun
AY
Cheng
Fang
F
Guan
Wuxiang
W
Johnson
F Brent
FB
Qiu
Jianming
J
D000818:Animals; D052660:Bocavirus / Q000235:genetics* / Q000502:physiology; D002460:Cell Line; D003001:Cloning, Molecular; D004252:DNA Mutational Analysis; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics*; D004285:Dogs; D055029:Inverted Repeat Sequences; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D012322:RNA Precursors / Q000096:biosynthesis; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000235:genetics; D014779:Virus Replication
D004279:DNA, Viral; D012322:RNA Precursors; D014764:Viral Proteins