HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Béliveau, C. Articles by Bellemare, G. Search for Related Content PubMed PubMed Citation Articles by Béliveau, C. Articles by Bellemare, G. Agricola Articles by Béliveau, C. Articles by Bellemare, G.

Expression of a Tranosema rostrale polydnavirus gene in the spruce budworm, Choristoneura fumiferana

Département de Biochimie, Pavillon Charles-Eugène-Marchand, Université Laval, Sainte-Foy, QC, Canada G1K 7P4¹
Laurentian Forestry Centre, Canadian Forest Service, Natural Resource Canada, PO Box 3800, Sainte-Foy, QC, Canada G1V 4C7²

Authors for correspondence: Guy Bellemare (fax +1 418 656 7176. e-mail bellemar{at}rsvs.ulaval.ca) and Michel Cusson (fax +1 418 648 5849; e-mail cusson@cfl.forestry.ca)

The endoparasitic wasp Tranosema rostrale (Ichneumonidae) transmits a polydnavirus (PDV) to its host, Choristoneura fumiferana, during oviposition. Unlike most other PDVs examined, the virus of T. rostrale (TrPDV) does not appear to play an important role in suppressing the host cellular immune response. However, it inhibits host metamorphosis. In the present study, TrPDV gene expression was examined in parasitized and virus-injected last-instar caterpillars. Northern analysis with viral DNA as a probe revealed only one detectable mRNA, of about 650 bp. The corresponding cDNA, termed TrV1, was cloned and sequenced and found to encode a protein of 103 amino acids which, following cleavage of the putative signal peptide, has a predicted molecular mass of 9·3 kDa. This protein displays limited similarity to the VHv1.4 cysteine-rich protein from the PDV of Campoletis sonorensis, mostly within the signal peptide region. By using a TrV1-specific probe, the TrV1 gene was localized to segment G of the TrPDV genome. The cuticle and fat body were identified as the principal sites of TrV1 transcription, with little transcription observed in haemocytes and midgut. Western analysis of proteins extracted from selected tissues of parasitized insects suggested that the TrV1 protein is secreted in the haemolymph. As observed for other PDVs, injection of TrPDV did not suppress transcription of the gene that encodes juvenile hormone esterase, the activity of which is inhibited by the virus. We speculate that the TrV1 protein may play a role in the inhibition of C. fumiferana metamorphosis.

This article has been cited by other articles:

				D. Stoltz, R. Lapointe, A. Makkay, and M. Cusson Exposure of ichnovirus particles to digitonin leads to enhanced infectivity and induces fusion from without in an in vitro model system J. Gen. Virol., November 1, 2007; 88(11): 2977 - 2984. [Abstract] [Full Text] [PDF]

				R. Lapointe, K. Tanaka, W. E. Barney, J. B. Whitfield, J. C. Banks, C. Beliveau, D. Stoltz, B. A. Webb, and M. Cusson Genomic and Morphological Features of a Banchine Polydnavirus: Comparison with Bracoviruses and Ichnoviruses J. Virol., June 15, 2007; 81(12): 6491 - 6501. [Abstract] [Full Text] [PDF]

				D. Doucet, A. Levasseur, C. Beliveau, R. Lapointe, D. Stoltz, and M. Cusson In vitro integration of an ichnovirus genome segment into the genomic DNA of lepidopteran cells J. Gen. Virol., January 1, 2007; 88(1): 105 - 113. [Abstract] [Full Text] [PDF]

				D. E. Gundersen-Rindal and M. J. Pedroni Characterization and transcriptional analysis of protein tyrosine phosphatase genes and an ankyrin repeat gene of the parasitoid Glyptapanteles indiensis polydnavirus in the parasitized host J. Gen. Virol., February 1, 2006; 87(2): 311 - 322. [Abstract] [Full Text] [PDF]

				E. Espagne, V. Douris, G. Lalmanach, B. Provost, L. Cattolico, J. Lesobre, S. Kurata, K. Iatrou, J.-M. Drezen, and E. Huguet A Virus Essential for Insect Host-Parasite Interactions Encodes Cystatins J. Virol., August 1, 2005; 79(15): 9765 - 9776. [Abstract] [Full Text] [PDF]

				A. Johner and B. Lanzrein Characterization of two genes of the polydnavirus of Chelonus inanitus and their stage-specific expression in the host Spodoptera littoralis J. Gen. Virol., May 1, 2002; 83(5): 1075 - 1085. [Abstract] [Full Text] [PDF]

				S. Wyder, A. Tschannen, A. Hochuli, A. Gruber, V. Saladin, S. Zumbach, and B. Lanzrein Characterization of Chelonus inanitus polydnavirus segments: sequences and analysis, excision site and demonstration of clustering J. Gen. Virol., January 1, 2002; 83(1): 247 - 256. [Abstract] [Full Text] [PDF]