Mémoire

Ultrastructural study of Pirhemocyton virus in lizard erythrocytes

Étude ultrastructurale du virus Pirhemocyton des érythrocytes de lézards

¹ Electron Microscopy Unit, Pathologic Anatomy Department, Curry Cabral Infectious Diseases Hospital, and Structural Biology and Development Section of the Department of Zoology and Anthropology, Lisbon University, Lisbon, Portugal.
² Department of Animal Sciences, Faculty of Agriculture of the Hebrew University of Jerusalem, Rehovot 76-100, Israel.

Accepted: 22 September 1992

Abstract

Ultrastructural study of Pirhemocyton infection in the lizard Agama impalearis, and the geckoes Tarentola mauritanica, Ptyodactylus hasselquistii, Gehyra australis and Heteronotia binoei confirmed is viral nature. Despite the apparent structural similarity, being all icosahedral iridovirus-like, virions from the diverse saurian hosts differed in size, nucleoid morphology and cytopathic effects on the erythocytes of their respective hosts. Virions from gecko infections were altogether larger than those found in A. impalearis. In the latter there was also no vacuole formation. The gecko infections are very different from one another in the pattern of their cytoplasmic membranes and the nature of their vacuoles. In P. hasselquistii virions became associated with the vacuole binding membrane. In the other geckoes the vacuole was an unbound inclusion of osmiophilic substance, very different from that found in the vacuole of P. hasselquistii.

Résumé

L’étude ultrastructurale de l’infection par Pirhemocyton du lézard Agama impalearis et des geckos Tarentola mauritanica, Ptyodactylus hasselquistii, Gehyra australis et Heteronotia binoei a permis de confirmer sa nature virale.

Malgré leur apparente similitude structurale, tous ayant le type iridovirus icosahédrique, les virions provenant de sauriens différents se différencient par leur taille, la morphologie nucléoïde et l’effet cytopathogène sur les érythrocytes.

Les infections des geckos diffèrent de façon importante l’une de l’autre par la morphologie de leurs membranes et la nature de leur vacuole. Chez P. hasselquistii les virions s’associent à la membrane limitante de la vacuole. Chez les autres geckos la vacuole est une inclusion de substance osmiophile non limitée par une membrane et très différente de celle qui est observée dans la vacuole de P. hasselquistii.