title: Gene-expression profiling of White spot syndrome virus in vivo.
abstract: White spot syndrome virus, type species of the genus Whispovirus in the family Nimaviridae, is a large, double-stranded DNA (dsDNA) virus that infects crustaceans. The genome of the completely sequenced isolate WSSV-TH encodes 184 putative open reading frames (ORFs), the functions of which are largely unknown. To study the transcription of these ORFs, a DNA microarray was constructed, containing probes corresponding to nearly all putative WSSV-TH ORFs. Transcripts of 79 % of these ORFs could be detected in the gills of WSSV-infected shrimp (Penaeus monodon). Clustering of the transcription profiles of the individual genes during infection showed two major classes of genes: the first class reached maximal expression at 20 h post-infection (p.i.) (putative early) and the other class at 2 days p.i. (putative late). Nearly all major and minor structural virion-protein genes clustered in the latter group. These data provide evidence that, similar to other large, dsDNA viruses, the WSSV genes at large are expressed in a coordinated and cascaded fashion. Furthermore, the transcriptomes of the WSSV isolates WSSV-TH and TH-96-II, which have differential virulence, were compared at 2 days p.i. The TH-96-II genome encodes 10 ORFs that are not present in WSSV-TH, of which at least seven were expressed in P. monodon as well as in crayfish (Astacus leptodactylus), suggesting a functional but not essential role for these genes during infection. Expression levels of most other ORFs shared by both isolates were similar. Evaluation of transcription profiles by using a genome-wide approach provides a better understanding of WSSV transcription regulation and a new tool to study WSSV gene function.
authors.affiliation: Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Marks
authors.affiliation: Plant Research International, Postbus 16, 6700 AA Wageningen, The Netherlands.
authors.forename: Oscar
authors.initials: O
authors.lastname: Vorst
authors.affiliation: Plant Research International, Postbus 16, 6700 AA Wageningen, The Netherlands.
authors.forename: Adèle M M L
authors.initials: AMML
authors.lastname: van Houwelingen
authors.affiliation: Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands.
authors.forename: Mariëlle C W
authors.initials: MCW
authors.lastname: van Hulten
authors.affiliation: Laboratory of Virology, Wageningen University, Binnenhaven 11, 6709 PD Wageningen, The Netherlands.
authors.forename: Just M
authors.initials: JM
authors.lastname: Vlak
mesh_terms: D000818:Animals; D020869:Gene Expression Profiling; D015967:Gene Expression Regulation, Viral; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D016366:Open Reading Frames; D033561:Penaeidae / Q000821:virology*; D020543:Proteome; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*; D046848:White spot syndrome virus 1 / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity*
chemical_list: D020543:Proteome; D014764:Viral Proteins