title: Bombyx mori nucleopolyhedrovirus ORF54, a viral desmoplakin gene, is associated with the infectivity of budded virions.
abstract: Bombyx mori nucleopolyhedrovirus (BmNPV) ORF54 (Bm54), a member of the viral desmoplakin N-terminus superfamily, is homologous to Autographa californica nucleopolyhedrovirus (AcMNPV) ORF66, which is required for the efficient egress of nucleocapsids from the nucleus and occlusion body formation. In this paper, we generated a bacmid with the Bm54 gene deleted via homologous recombination in Escherichia coli and characterized the mutant virus using a transfection-infection assay and transmission electron microscopy analysis. Our results demonstrated that the cells transfected with viral DNA lacking Bm54 produced non-infectious budded viruses (BVs). Electron microscopy showed that although the deletion of Bm54 did not affect assembly and release of nucleocapsids, it severely affected polyhedron formation. In conclusion, deletion of Bm54 resulted in non-infectious BV and defective polyhedra. Although the sequences of Bm54 and Ac66 are very similar, the two genes function quite differently in the regulation of viral life cycle.
authors.affiliation: Ministry of Agriculture Key Laboratory of Agricultural Entomology, Institute of Insect Science, Zhejiang University, Yuhangtang Road 866, Hangzhou, 310058 Zhejiang, China.
authors.forename: Min-Juan
authors.initials: MJ
authors.lastname: Zhang
authors.forename: Cai-Hong
authors.initials: CH
authors.lastname: Tian
authors.forename: Xiao-Ying
authors.initials: XY
authors.lastname: Fan
authors.forename: Yi-Han
authors.initials: YH
authors.lastname: Lou
authors.forename: Ruo-Lin
authors.initials: RL
authors.lastname: Cheng
authors.forename: Chuan-Xi
authors.initials: CX
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000914:Antibodies, Viral; D012831:Bombyx / Q000166:cytology / Q000648:ultrastructure / Q000821:virology*; D002478:Cells, Cultured; D051180:Desmoplakins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D015967:Gene Expression Regulation, Viral / Q000502:physiology; D046529:Microscopy, Electron, Transmission; D017924:Nucleopolyhedroviruses / Q000145:classification* / Q000235:genetics* / Q000502:physiology / Q000648:ultrastructure; D010802:Phylogeny; D011817:Rabbits; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D014779:Virus Replication / Q000502:physiology
chemical_list: D000914:Antibodies, Viral; D051180:Desmoplakins; D014764:Viral Proteins