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Avian reoviruses belong to the genus ''Orthoreovirus'', and ''Reoviridae'' family. They are non-enveloped viruses that undergo replication in the cytoplasm of infected cells. It has icosahedral symmetry and contains a double-shelled arrangement of surface protein. Virus particles can range between 70-80 nm. Morphologically, the virus is a double stranded RNA virus that is composed of ten segments. The genome and proteins that are encoded by the genome can be separated into three different sizes ranging from small, medium, or large. Of the eleven proteins that are encoded for by the genome, two are nonstructural, while the remaining nine are structural. Avian reoviruses can withstand a pH range of 3.0-9.0. Ambient temperatures are suitable for the survival of these viruses, which become inactive at 56 C in less than an hour. Common areas where this virus can survive include galvanized metal, glass, rubber, feathers, and wood shavings. Avian reovirus can survive for up to ten days on these common areas in addition to up to ten weeks in water. Cultivation and observation of the effects of avian reovirus is most often performed in chicken embryos. If infected into the yolk sac, the embryo will succumb to death accompanied by hemorrhaging of the embryos and cause the foci on the liver to appear yellowish-green. There are several primary chicken cell cultures/areas that are susceptible to avian reoviruses, which include the lungs, liver, kidney, and fibroblasts of the chick embryo. Of the following susceptible areas, liver cells from the chick embryo have been found to be the most sensitive for primary isolation from clinical material. Typically, the CPE effect of avian reoviruses is the production of syncytia. CPE, or cytopathic effects are the visible changes in a host cell that takes place because of viral infection. Syncytia is a single cell or cytoplasmic mass containing several nuclei, formed by fusion of cells or by division of nuclei. ==Genome structure== The complete genome sequence of avian reovirus is 23,494 bp long and is broken up into 10 segments. The full lengths of each segment are L1 (3,959 nt), L2 (3,830 nt), L3 (3,907 nt), M1 (2,283 nt), M2 (2,158 nt), M3 (1,996 nt), S1 (1,643 nt), S2 (1,324 nt), S3 (1,202 nt), and S4 (1,192 nt). There are 10 proteins that are also involved in the composition of this virus. The lengths of these structural and non-structural proteins are λa (1,293 amino acids), λB (1,259 aa), λC (1,285 aa), μA (732 aa), μB (676 aa), μNS (635 aa), σC (326 aa), σA (416 aa), σB (367 aa), and σNS (367 aa). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Avian Reovirus」の詳細全文を読む スポンサード リンク
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