title: Analysis of proteins encoded in the bipartite genome of a new type of parvo-like virus isolated from silkworm - structural protein with DNA polymerase motif.
abstract: Bombyx mori densonucleosis virus type 2 (BmDNV-2) is a small, spherical virus containing two complementary single-stranded linear DNA molecules (VD1, VD2). BmDNV-2 is a new type of virus with a unique, yet unspecified replication mechanism which is different from that of parvoviruses (Bando, H., Choi, H., Ito, Y., Nakagaki, M. , Kawase, S., 1992. Structural analysis on the single-stranded genomic DNAs of the virus newly isolated from silkworm: the DNA molecules share a common terminal sequence, Arch. Virol. 124, 187-193; Bando, H., Hayakawa, T., Asano, S., Sahara, K., Nakagaki, M. , Iizuka, T., 1995. Analysis of the genetic information of a DNA segment of a new virus from silkworm, Arch. Virol., 140, 1147-1155; Hayakawa, T., Asano, S., Sahara, K., Iizuka, T., Bando, H., 1997. Detection of replicative intermediate with closed terminus of Bombyx densonucleosis virus. Arch. Virol. 142, 1-7). Recent analyses on the genomic information of BmDNV-2 identified open reading frames which code for three tentative nonstructural proteins and four (VP1 to 4) of the six known structural proteins (Bando, H., Hayakawa, T., Asano, S., Sahara, K., Nakagaki, M., Iizuka, T., 1995. Analysis of the genetic information of a DNA segment of a new virus from silkworm, Arch. Virol., 140, 1147-1155; Nakagaki et al., in preparation). In this report we demonstrate that the two largest ORFs, VD1-ORF1 and VD2-ORF1, code for the two remaining structural proteins. In addition, computer-assisted analysis revealed that the structural protein encoded in VD1-ORF1 contains sequences conserved among various DNA polymerases, and showed an evolutionary relationship with the DNA polymerases involved in protein-primed replication.
authors.affiliation: Division of Applied Bioscience, Faculty of Agriculture, Hokkaido University, Sapporo 060, Hokkaido, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Hayakawa
authors.forename: K
authors.initials: K
authors.lastname: Kojima
authors.forename: K
authors.initials: K
authors.lastname: Nonaka
authors.forename: M
authors.initials: M
authors.lastname: Nakagaki
authors.forename: K
authors.initials: K
authors.lastname: Sahara
authors.forename: S i
authors.initials: Si
authors.lastname: Asano
authors.forename: T
authors.initials: T
authors.lastname: Iizuka
authors.forename: H
authors.initials: H
authors.lastname: Bando
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D012831:Bombyx / Q000821:virology*; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D017990:Densovirus / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D016679:Genome, Viral; D008969:Molecular Sequence Data; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D015678:Viral Structural Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D015678:Viral Structural Proteins; D004259:DNA-Directed DNA Polymerase