JOURNAL
OP INVERTEBRATE
PATHOLOGY
29, 241-249 (1977)
Viruslike Particles in Peripheral Nerve of the House Cricket In the course of ultrastructural studies were any particles observed in glial nuclei on the cereal sensory nerve on the house or within neurons. cricket, Acheta domesticus, we have occaThe particles themselves are about 16sionally encountered virus-like inclusions in 20 by 50-55 nm and in cross section appear nerves of apparently healthy animals from to contain a central density. They are of normal populations. Since reports of viral similar dimension but are readily disinfection of orthopteroid insects are rela- tinguishable from microtubules (Fig. 2). tively rare, we record here preliminary obPrevious reports of viruses in Orthoptera servations in a widely used experimental are few [W. A. L. David, Zn “Annual orthopteran which is raised on a commercial Review of Entomology” (R. F. Smith et al., scale as a food source for vivaria and as eds.), pp. 97-149, Annual Reviews, Palo fresh bait. Alto, Calif., 19751; until 1966 they were Adult animals from bulk cultures (> 10001 unknown (K. M. Smith, “Insect Virology,” m3) purchased from Flukers Cricket Farm, 256 pp., Academic Press, New York, 1967). Baton Rouge, Louisiana, and maintained in The intracellular particles in the matrices laboratory cultures on lettuce and dried described above most closely resemble the cat food were used. Lengths of cereal nonoccluded viruses observed in field nerve were dissected out and fixed in 2% crickets (C. Reinganum, G. T. O’Loughlin, paraformaldehyde and 0.5% glutaraIdehyde and T. W. Hogan, J. Znvertebr. Pathol. 16, in Millonig phosphate buffer, PH 7.3, post214-220, 1970). This virus causes a fatal fixed in 2% osmium, and embedded in paralysis, usually in the nymphs, as does Epon. Thin sections were doubly stained the virus reported from Grylius bimaculatus in uranyl acetate and lead citrate and ex- by G. Meynadier (C. R. Acad. Sci. Paris amined in a Philips 300 electron microscope. Ser. D, 263, 742-744, 1966). No evidence Extracellular virus-like particles were has been found for pathogenicity in our found between glial folds and in the colla- cultures. Size alone suggests that the genous neural lamella (Fig. 1). In both loca- particles may be paroviruses or enterotions they appeared to be randomly ori- viruses. ented. Their density was greatest between We thank Dr. R. A. Cloney, Department of Zoology glial folds (Fig. 2). In contrast, intracellular and Dr. E. S. Boatman, Department of Pathoparticles were less numerous and formed biology, for their comments on the material. Supordered matrices within organelles that we ported in part by NIH Grant NB 07778. tentatively consider to be lysosomes (Fig. R. E. MORRISSEY 1). Similar particles may be arranged like J. S. EDWARDS stacks of coins (Figs. 3, 4); still others are Department of Zoology found free in the cytoplasm but have a ranUniversity of Washington dom orientation similar to that of the extraSeattle, Washington 98195 Received June 23, 1976 cellular particles (Fig. 2, inset). In no case
247 Copyright 0 I977 by Academic Press, Inc. All rights of reproduction in any form reserved
ISSN WDL?Ol I
248
NOTES
FIG. 1. Electron micrograph of the margin of the cereal nerve of the cricket. Arrows indicate like particles in the neural lamella (nl), between the @aI folds, and associated with what may bea lysosome (1~s). Scale = 1 pm. FIG. 2. High magnification of virus-like materiai between glial folds. Inset shows intracellular pat-tides randomly oriented in the cytoplasm of a glial cell. Microtubules (mt) provide a size comparison. Scale = 0.1 Frn for both micrographs.
249
FIG, 3. Margin of a cereal nerve showing part of a g&al nucieus (ttucf and what appear to be Iysosomes containing stacks of virus-like particles (arrowheads). Neural lamella, nl. Scale = 3 pm. FIG, 4. Higher rn~n~~cation of matrices (arrow) of virus-like material. space occi Ipied by acid mucopolysaccharide material. Scale = 0.1 pm.
Stars denote
extraceltular
OP INVERTEBRATE
PATHOLOGY
29, 241-249 (1977)
Viruslike Particles in Peripheral Nerve of the House Cricket In the course of ultrastructural studies were any particles observed in glial nuclei on the cereal sensory nerve on the house or within neurons. cricket, Acheta domesticus, we have occaThe particles themselves are about 16sionally encountered virus-like inclusions in 20 by 50-55 nm and in cross section appear nerves of apparently healthy animals from to contain a central density. They are of normal populations. Since reports of viral similar dimension but are readily disinfection of orthopteroid insects are rela- tinguishable from microtubules (Fig. 2). tively rare, we record here preliminary obPrevious reports of viruses in Orthoptera servations in a widely used experimental are few [W. A. L. David, Zn “Annual orthopteran which is raised on a commercial Review of Entomology” (R. F. Smith et al., scale as a food source for vivaria and as eds.), pp. 97-149, Annual Reviews, Palo fresh bait. Alto, Calif., 19751; until 1966 they were Adult animals from bulk cultures (> 10001 unknown (K. M. Smith, “Insect Virology,” m3) purchased from Flukers Cricket Farm, 256 pp., Academic Press, New York, 1967). Baton Rouge, Louisiana, and maintained in The intracellular particles in the matrices laboratory cultures on lettuce and dried described above most closely resemble the cat food were used. Lengths of cereal nonoccluded viruses observed in field nerve were dissected out and fixed in 2% crickets (C. Reinganum, G. T. O’Loughlin, paraformaldehyde and 0.5% glutaraIdehyde and T. W. Hogan, J. Znvertebr. Pathol. 16, in Millonig phosphate buffer, PH 7.3, post214-220, 1970). This virus causes a fatal fixed in 2% osmium, and embedded in paralysis, usually in the nymphs, as does Epon. Thin sections were doubly stained the virus reported from Grylius bimaculatus in uranyl acetate and lead citrate and ex- by G. Meynadier (C. R. Acad. Sci. Paris amined in a Philips 300 electron microscope. Ser. D, 263, 742-744, 1966). No evidence Extracellular virus-like particles were has been found for pathogenicity in our found between glial folds and in the colla- cultures. Size alone suggests that the genous neural lamella (Fig. 1). In both loca- particles may be paroviruses or enterotions they appeared to be randomly ori- viruses. ented. Their density was greatest between We thank Dr. R. A. Cloney, Department of Zoology glial folds (Fig. 2). In contrast, intracellular and Dr. E. S. Boatman, Department of Pathoparticles were less numerous and formed biology, for their comments on the material. Supordered matrices within organelles that we ported in part by NIH Grant NB 07778. tentatively consider to be lysosomes (Fig. R. E. MORRISSEY 1). Similar particles may be arranged like J. S. EDWARDS stacks of coins (Figs. 3, 4); still others are Department of Zoology found free in the cytoplasm but have a ranUniversity of Washington dom orientation similar to that of the extraSeattle, Washington 98195 Received June 23, 1976 cellular particles (Fig. 2, inset). In no case
247 Copyright 0 I977 by Academic Press, Inc. All rights of reproduction in any form reserved
ISSN WDL?Ol I
248
NOTES
FIG. 1. Electron micrograph of the margin of the cereal nerve of the cricket. Arrows indicate like particles in the neural lamella (nl), between the @aI folds, and associated with what may bea lysosome (1~s). Scale = 1 pm. FIG. 2. High magnification of virus-like materiai between glial folds. Inset shows intracellular pat-tides randomly oriented in the cytoplasm of a glial cell. Microtubules (mt) provide a size comparison. Scale = 0.1 Frn for both micrographs.
249
FIG, 3. Margin of a cereal nerve showing part of a g&al nucieus (ttucf and what appear to be Iysosomes containing stacks of virus-like particles (arrowheads). Neural lamella, nl. Scale = 3 pm. FIG, 4. Higher rn~n~~cation of matrices (arrow) of virus-like material. space occi Ipied by acid mucopolysaccharide material. Scale = 0.1 pm.
Stars denote
extraceltular
