The N-terminal hydrophobic sequence of Autographa californica nucleopolyhedrovirus PIF-3 is essential for oral infection.
The Autographa californica nucleopolyhedrovirus (AcMNPV) open reading frame 115 has been identified as a per os infection factor (pif-3) and is essential for oral infection. Here, we have characterized the pif-3 of AcMNPV in more detail. The pif-3 transcripts were detected from 12 to 96 h post-infection (hpi) in Sf9 cells infected with AcMNPV. Polyclonal antiserum first recognized a 25-kDa protein at 36 hpi. Western blot analysis indicated that PIF-3 is a component of occlusion-derived virus but not of budded virus. The subcellular localization demonstrated that the 21-amino-acid (aa) N-terminal hydrophobic domain of PIF-3, which is conserved in PIF-1, PIF2 and PIF-3, acts as a nuclear location signal and is essential for trafficking the protein to the nucleus. Deletion of either pif-3 or the 21-aa N-terminal hydrophobic domain of pif-3 from AcMNPV abolished per os infectivity but had no effect on the infectivity of the budded virus phenotype.
Li
X
X
State Key Laboratory of Virology, Wuhan Institute of Virology, The Chinese Academy of Sciences, Wuhan, PR China.
Song
J
J
Jiang
T
T
Liang
C
C
Chen
X
X
D000595:Amino Acid Sequence; D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D002478:Cells, Cultured; D004064:Digestive System / Q000821:virology; D004926:Escherichia coli / Q000235:genetics; D017353:Gene Deletion; D005814:Genes, Viral; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D019476:Insect Proteins / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D007814:Larva / Q000821:virology; D008969:Molecular Sequence Data; D019913:Nuclear Localization Signals / Q000737:chemistry; D017924:Nucleopolyhedroviruses / Q000737:chemistry* / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity*; D016366:Open Reading Frames; D017434:Protein Structure, Tertiary; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D017422:Sequence Analysis, DNA; D018411:Spodoptera / Q000166:cytology / Q000821:virology*; D013347:Subcellular Fractions / Q000378:metabolism; D013997:Time Factors; D014162:Transfection; D010948:Viral Plaque Assay
D019476:Insect Proteins; D019913:Nuclear Localization Signals; D012367:RNA, Viral; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins