Trisymmetrons and tubular forms of iridovirus from the mosquito Aedes (Ochlerotatus) cantans (Meigen, 1818) (Diptera: Culicidae)

Mosquito iridescent viruses (MIV) were isolated in Ukraine from the larvae of the bloodsucking mosquito Aedes (Ochlerotatus) cantans (Meigen, 1818) (Diptera: Culicidae) that were infected. Examination of ultrathin sections of infected mosquito fat body cells revealed that MIV virion maturation occurs in the cytoplasm. The virions were spherical with pentagonal and hexagonal outlines, indicating icosahedral symmetry. In addition to spherical virions with a diameter of 190 ± 5 nm, smaller tubular structures were present in the cytoplasm of infected cells. Upon destroying the purified virus, a large number of trisymmetrons were identified. Each trisymmetron consists of 55 hexagonally arranged subunits that form an isosceles triangle with an edge length of 60 nm