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 Bigot, Y. Articles by Federici, B. A. Search for Related Content PubMed PubMed Citation Articles by Bigot, Y. Articles by Federici, B. A. Agricola Articles by Bigot, Y. Articles by Federici, B. A.

Characterization of repetitive DNA regions and methylated DNA in ascovirus genomes

IRBI, Groupe d’Etude des Parasites Moléculaires, UPRESA CNRS 6035, Faculté des Sciences, Parc de Grandmont, 37200 Tours, France¹
Department of Entomology and Interdepartmental Graduate Program in Genetics, University of California, Riverside, CA 92521, USA²

Author for correspondence: Yves Bigot (at the IRBI). Fax +33 47 36 69 66. e-mail Bigot{at}univ-tours.fr

The accompanying phylogenetic study of large double-stranded DNA viruses based on their DNA polymerase genes suggests that ascoviruses (family Ascoviridae) and iridoviruses (family Iridoviridae) are closely related and may share a common ancestor. This relationship was unexpected because of marked differences between these viruses. Iridoviruses produce icosahedral virions and occur broadly among vertebrates and invertebrates, whereas ascoviruses typically produce reniform or bacilliform virions and are restricted to insect hosts, primarily lepidopterans. Detailed comparisons of these two virus types are not possible because fundamental information on the properties of the virions and their genomes is lacking, especially for ascoviruses. To facilitate further investigation of the putative evolutionary relationship between ascoviruses and iridoviruses, the genomes of representative viruses from each family were compared with respect to physical configuration, presence of DNA repeats and degree of DNA methylation. Genomes from Spodoptera frugiperda (SfAV1), Heliothis virescens (HvAV3) and Diadromus pulchellus (DpAV4) ascoviruses were all found to be circular and partially superhelical and to contain large interspersed repeats of 1–3 kbp. Mosquito (IV type 3), lepidopteran (IV type 6) and isopod (IV type 31) iridovirus genomes were all linear and lacked large regions of repetitive DNA. Ascovirus and iridovirus genomes were methylated and one, DpAV4, had the highest degree of methylation of any reported animal DNA virus. The major differences in the physical and biochemical characteristics of ascoviruses and iridoviruses reported here provide a foundation for further studies of their relatedness while making their possible close relationship and divergence during evolution of even greater interest.

This article has been cited by other articles:

				M. Hussain, R. J. Taft, and S. Asgari An Insect Virus-Encoded MicroRNA Regulates Viral Replication J. Virol., September 15, 2008; 82(18): 9164 - 9170. [Abstract] [Full Text] [PDF]

				K. Hoelzer, L. A. Shackelton, and C. R. Parrish Presence and role of cytosine methylation in DNA viruses of animals Nucleic Acids Res., May 1, 2008; 36(9): 2825 - 2837. [Abstract] [Full Text] [PDF]

				D. K. Bideshi, M.-V. Demattei, F. Rouleux-Bonnin, K. Stasiak, Y. Tan, S. Bigot, Y. Bigot, and B. A. Federici Genomic Sequence of Spodoptera frugiperda Ascovirus 1a, an Enveloped, Double-Stranded DNA Insect Virus That Manipulates Apoptosis for Viral Reproduction J. Virol., December 1, 2006; 80(23): 11791 - 11805. [Abstract] [Full Text] [PDF]

				G. Delhon, E. R. Tulman, C. L. Afonso, Z. Lu, J. J. Becnel, B. A. Moser, G. F. Kutish, and D. L. Rock Genome of Invertebrate Iridescent Virus Type 3 (Mosquito Iridescent Virus) J. Virol., September 1, 2006; 80(17): 8439 - 8449. [Abstract] [Full Text] [PDF]

				G. P. Pijlman, J. E. van Schijndel, and J. M. Vlak Spontaneous excision of BAC vector sequences from bacmid-derived baculovirus expression vectors upon passage in insect cells J. Gen. Virol., October 1, 2003; 84(10): 2669 - 2678. [Abstract] [Full Text] [PDF]

				D. K. Bideshi, S. Renault, K. Stasiak, B. A. Federici, and Y. Bigot Phylogenetic analysis and possible function of bro-like genes, a multigene family widespread among large double-stranded DNA viruses of invertebrates and bacteria J. Gen. Virol., September 1, 2003; 84(9): 2531 - 2544. [Abstract] [Full Text] [PDF]

				K. Stasiak, M.-V. Demattei, B. A. Federici, and Y. Bigot Phylogenetic position of the Diadromus pulchellus ascovirus DNA polymerase among viruses with large double-stranded DNA genomes J. Gen. Virol., December 1, 2000; 81(12): 3059 - 3072. [Abstract] [Full Text]