Peroral infectivity of non-occluded viruses of Bombyx mori nucleopolyhedrovirus and polyhedrin-negative recombinant baculoviruses to silkworm larvae is drastically enhanced when administered with Anomala cuprea entomopoxvirus spindles.

Non-occluded viruses (NOVs) of Bombyx mori nucleopolyhedrovirus (BmNPV) are poorly infectious to silkworm larvae when administered by peroral inoculation, although they are highly infectious when injected into the insect haemocoel. In the present study, it is demonstrated that NOVs of BmNPV became highly infectious even through peroral inoculation when administered with spindles (proteinaceous structures) of Anomala cuprea entomopoxvirus (AcEPV). Marked enhancement of peroral infectivity of NOVs by AcEPV spindles (nearly 1000-fold higher in the strongest case) was observed in all growth stages of silkworm larvae tested (2nd to 5th instar). Similarly, peroral infectivity of polyhedrin-negative recombinants of BmNPV, which do not produce polyhedra, was also enhanced remarkably by AcEPV spindles. In contrast, spheroids (proteinaceous structures containing AcEPV virions) did not enhance the peroral infectivity of either NOVs or the recombinant BmNPV in silkworm larvae.

[1]  A. Wijonarko,et al.  Detection of a virus enhancing factor in the spheroid, spindle, and virion of an entomopoxvirus. , 1998, Journal of invertebrate pathology.

[2]  W. Mitsuhashi,et al.  The Spindles of an Entomopoxvirus ofColeoptera(Anomala cuprea) Strongly Enhance the Infectivity of a Nucleopolyhedrovirus inLepidoptera(Bombyx mori) , 1998 .

[3]  Mitsuhashi,et al.  The spindles of an entomopoxvirus of coleoptera (Anomala cuprea) strongly enhance the infectivity of a nucleopolyhedrovirus in lepidoptera , 1998, Journal of invertebrate pathology.

[4]  W. Mitsuhashi,et al.  Complete nucleotide sequence of the fusolin gene of an entomopoxvirus in the cupreous chafer, Anomala cuprea Hope (Coleoptera: Scarabaeidae). , 1997, Insect biochemistry and molecular biology.

[5]  P. Wang,et al.  An intestinal mucin is the target substrate for a baculovirus enhancin. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[6]  J. Sun,et al.  Purification, Characterization and cDNA Cloning of a Novel Anticoagulant of the Intrinsic Pathway, (Prolixin-S), from Salivary Glands of the Blood Sucking Bug, Rhodnius prolixus , 1996, Thrombosis and Haemostasis.

[7]  T. Hayakawa,et al.  Cloning and sequencing of the gene for an enhancing factor from Pseudaletia separata entomopoxvirus. , 1996, Gene.

[8]  M. Shapiro,et al.  In Vitro Effects of Fluorescent Brightener on the Efficacy of Occlusion Body Dissolution and Polyhedral-Derived Virions , 1995 .

[9]  M. Tomita,et al.  Detection of a Virus Enhancing Factor in Inclusion Bodies of an Entomopoxvirus by Immunoelectron Microscopy , 1995 .

[10]  J. Kobayashi,et al.  Efficient lipofection method for transfection of the silkworm cell line, NISES-BoMo-15AIIc, with the DNA genome of the Bombyx mori nuclear polyhedrosis virus , 1993 .

[11]  A. Sriskantha,et al.  A gene encoding a highly expressed spindle body protein of Heliothis armigera entomopoxvirus. , 1993, The Journal of general virology.

[12]  L. Volkman,et al.  Autographa californica nuclear polyhedrosis virus: comparative infectivity of the occluded, alkali-liberated, and nonoccluded forms. , 1977, Journal of invertebrate pathology.

[13]  T. Kawarabata.  Highly infectious free virions in the hemolymph of the silkworm (Bombyx mori) infected with a nuclear polyhedrosis virus. , 1974, Journal of invertebrate pathology.

[14]  M. Bergoin,et al.  Isolation and amino acid composition of the inclusions of Melolontha melolontha poxvirus. , 1970, Virology.

[15]  O. Heinisch.  Finney, D. J.: Statistical method in biological assay. 2. Aufl. Charles Griffin & Cc. Ltd., London 1964. XIX + 668 S., Preis 105 s , 1965 .