Autographa californica multiple nucleopolyhedrovirus ac142, a core gene that is essential for BV production and ODV envelopment.
Autographa californica multiple nucleopolyhedrovirus (AcMNPV) ac142 is a baculovirus core gene and encodes a protein previously shown to associate with occlusion-derived virus (ODV). To determine its role in the baculovirus life cycle, we used the AcMNPV bacmid system to generate an ac142 deletion virus (AcBAC(ac142KO-PH-GFP)). Fluorescence and light microscopy revealed that AcBAC(ac142KO-PH-GFP) exhibits a single-cell infection phenotype. Titration assays and Western blot confirmed that AcBAC(ac142KO-PH-GFP) is unable to produce budded virus (BV). However, viral DNA replication is unaffected and the development of occlusion bodies in AcBAC(ac142KO-PH-GFP)-transfected cells evidenced progression to very late phases of the viral infection. Western blot analysis showed that AC142 is expressed in the cytoplasm and nucleus throughout infection and that it is a structural component of BV and ODV which localizes to nucleocapsids. Electron microscopy indicates that ac142 is required for nucleocapsid envelopment to form ODV and their subsequent occlusion, a fundamental process to all baculoviruses.
Pacific Agri-Food Research Centre, Agriculture and Agri-Food Canada, Box 5000, Summerland, British Columbia, Canada V0H 1Z0.
Christina B
CB
McCarthy
Xiaojiang
X
Dai
Cam
C
Donly
David A
DA
Theilmann
D000818:Animals; D002460:Cell Line; D017353:Gene Deletion; D015967:Gene Expression Regulation, Viral; D020043:Genes, Essential / Q000235:genetics*; D005814:Genes, Viral / Q000235:genetics*; D019251:Nucleocapsid / Q000648:ultrastructure; D017924:Nucleopolyhedroviruses / Q000235:genetics* / Q000254:growth & development* / Q000648:ultrastructure; D018411:Spodoptera / Q000166:cytology; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D014777:Virus Diseases; D014779:Virus Replication / Q000235:genetics*
D014764:Viral Proteins