title: Identification of Bombyx mori bidensovirus VD1-ORF4 reveals a novel protein associated with viral structural component.
abstract: Bombyx mori bidensovirus (BmBDV) VD1-ORF4 (open reading frame 4, ORF4) consists of 3,318 nucleotides, which codes for a predicted 1,105-amino acid protein containing a conserved DNA polymerase motif. However, its functions in viral propagation remain unknown. In the current study, the transcription of VD1-ORF4 was examined from 6 to 96 h postinfection (p.i.) by RT-PCR, 5'-RACE revealed the transcription initiation site of BmBDV ORF4 to be -16 nucleotides upstream from the start codon, and 3'-RACE revealed the transcription termination site of VD1-ORF4 to be +7 nucleotides downstream from termination codon. Three different proteins were examined in the extracts of BmBDV-infected silkworms midguts by Western blot using raised antibodies against VD1-ORF4 deduced amino acid, and a specific protein band about 53 kDa was further detected in purified virions using the same antibodies. Taken together, BmBDV VD1-ORF4 codes for three or more proteins during the viral life cycle, one of which is a 53 kDa protein and confirmed to be a component of BmBDV virion.
authors: Institute of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China. liguohuijnl@yahoo.com.cn
authors: Guohui
authors: G
authors: Li
authors: Zhaoyang
authors: Z
authors: Hu
authors: Xuli
authors: X
authors: Guo
authors: Guangtian
authors: G
authors: Li
authors: Qi
authors: Q
authors: Tang
authors: Peng
authors: P
authors: Wang
authors: Keping
authors: K
authors: Chen
authors: Qin
authors: Q
authors: Yao
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx / Q000821:virology*; D018387:Codon, Initiator; D018388:Codon, Terminator; D004279:DNA, Viral / Q000235:genetics; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D017990:Densovirus / Q000235:genetics* / Q000254:growth & development; D005814:Genes, Viral; D016366:Open Reading Frames; D024363:Transcription Initiation Site; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology
chemical_list: D018387:Codon, Initiator; D018388:Codon, Terminator; D004279:DNA, Viral; D014764:Viral Proteins; D004259:DNA-Directed DNA Polymerase