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Deformed wing virus (DWV) is an RNA virus, one of 22 known viruses affecting honey bees. While most commonly infecting the honey bee, ''Apis mellifera'', it has also been documented in other bee species, like ''Bombus terrestris'', thus, indicating it may have a wider host specificity than previously anticipated. The virus was first isolated from a sample of symptomatic honeybees from Japan in the early 1980s and is currently distributed worldwide. Found also in pollen baskets and commercially reared bumblebees ((Graystock et al 2013 )). Its main vector in ''A. mellifera'' is the Varroa mite. It is named after what is usually the most obvious deformity it induces in the development of a honeybee pupa, which is shrunken and deformed wings, but other developmental deformities are often present. == Genomics == The viral genome was published in 2006.〔Lanzi G., de Miranda J.R., Boniotti M.B., Cameron C.E., Lavazza A., Capucci L., Camazine S.M., Rossi C. (2006) Molecular and biological characterization of deformed wing virus of honeybees (''Apis mellifera'' L.). J Virol. 2006 80(10):4998-5009〕 The genome is 10140 nucleotides in length excluding the poly(A) tail and contains a single large open reading frame encoding a 328-kilo Dalton (kDA) polyprotein. 5' of the central coding sequence is a 1144-nucleotide nontranslated leader sequence (UTR). 3' coding sequence is a 317-nucleotide nontranslated region which is followed by a poly(A) tail. The genome is 29.5% adenosine, 15.8% cytosine, 22.4% guanine and 32.3% uracil. Analysis of codon use found 39.5% uracil and 26.8% adenosine in the third base position.There are three major structural proteins - VP1 (44 kDa), VP2 (32 kDa), and VP3 (28 kDa). These lie in the N-terminal section of the polyprotein. The C-terminal part of the polyprotein contains sequence motifs typical of well-characterized picornavirus nonstructural proteins: an RNA helicase, a chymotrypsin-like 3C protease and an RNA-dependent RNA polymerase. VP1 is encoded between codons 486 to 880 and VP3 lies between codons 913 and 1063. The boundaries of VP2 are not as well defined but it is encoded 5' of VP1. There may be a small protein (VP4) encoded between codons 464 and 486 but this protein has not been confirmed to be present in the genome. Lying 5' to VP2 is a very variable leader peptide (L protein). Despite occupying 7.3% of the polyprotein it is responsible for 26.2% to 33.3% of the variation found between the Iflaviridae. It may be involved in the inhibition of host cap-dependent mRNA translation and stimulation of viral internal ribosome entry site activity. VPg, a small protein (23 amino acids) common to many RNA viruses, is responsible for stabilizing the 5' end of the genomic RNA for replication and translation. A putative VPg is present between nucleotide positions 2093 and 2118 immediately 5' of the 3C protease. The protein itself has not yet been confirmed to be present in the viron. The helicase domains A, B and C are found between codons 1460 and 1575. The 3C protease domains span codons 2183 to 2327. The usual eight RdRp domains are located between codons 2493 and 2828. The genome structure is 5'UTR-L-VP2-(VP4)-VP1-VP3-RNA helicase-(VPg)-3C protease-RNA dependent RNA polymerase-3'UTR The putative VP4 and VPg proteins are marked here by parentheses. If the VPg is present in the genome a copy will be bound to the 5' end of the RNA genome. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Deformed wing virus」の詳細全文を読む スポンサード リンク
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