Reovirus type 3

More recently, triple /1-spiral repeats have been identified in mammalian reovirus type 3 fiber (Chappell et al., 2002 Fig. 4A), avian reovirus fiber (Guardado Calvo et al., 2005 Fig. 4B), and bacteriophage PRD1 P5 protein (Merckel et al., 2005 Fig. 4C). In the latter two cases, it appears that only two repeats are present, just N-terminal to the head domain. Mammalian reovirus fiber contains eight putative triple /1-spiral repeats, of which three were resolved in the crystal structure (Chappell et al., 2002). 

Nibert, M. L., Chappell, J. D., and Dermody, T. S. (1995). Infectious subvirion particles of reovirus type 3 Dearing exhibit a loss in infectivity and contain a cleaved crl protein./. Virol. 69, 5057-5067. 

Spriggs, D. R., and Fields, B. N. (1982). Attenuated reovirus type 3 strains generated by selection of haemagglutinin antigenic variants. Nature 297, 68-70. 

The virus reduction studies of the three process steps discussed here were performed with HFV-l, Bovine viral diarrhea virus (BVDV), Pseudorabies virus (PRV), Reovirus type 3 (Reo), Hepatitis A virus (HAV), and Porcine parvovirus (PPV). HIV-1 was included as a relevant enveloped virus, while BVDV and PRV were tested as specific model viruses for HCV and HBV, respectively (Table 1). Reo was chosen as a non-specific model non-enveloped virus, HAV was included as a relevant virus and PPV was used as a surrogate for human parvovirus B19. All viruses were propagated using standard cell culture conditions. " The appropriate cell lines were infected, at a low multiplicity of infection, and incubated until 4-1- cytopathic effects were observed. The infected cells were frozen and thawed three times to release virus, centrifuged at low speed to remove cell debris and the clarified supernatants were removed for use as virus spikes. 

Reovirus type 3 (Reo) Hepatitis A virus (HAV) Porcine parvo virus (PPV)... 

Lymphocytic choriomeningitis virus Reovirus type 3 Sendai virus Ectromelia virus K virus... 

REOV-3 reovirus type 3 FVIII protein folding during biosynthesis. 

Whole hand Poliovirus type 1, echovirus 11 12, reovirus type 3, papovavirus SV40, adenovirus type 2, coxsackievirus type 4, vaccinia virus Alcohols, antiseptic products (V, VP 1, Desderman, Betaisodona) 66... 

Both of the above analyses were conducted on cells infected with the Bearing strain of reovirus, type 3. Sharpe and Fields (1982) showed that type 2 reovirus inhibits cellular protein synthesis more effectively than type 3. By isolating recombinant viruses containing various combinations of double-stranded RNA segments derived from both strains of reovirus, they demonstrated that the S4 RNA segment, which encodes the major outer capsid protein of the virion, is responsible for the ability of type 2 reovirus to inhibit L cell ma-cromolecular synthesis. Inactivation of type 2 reovirus by ultraviolet... 

In addition to the laboratory strains of type 1 and type 3, five field isolates collected by Rosen and co-workers of reovirus type 1 and 3 (Rosen and Abinanti, 1960 Rosen et al., 1963) were examined for their ability to inhibit L cell DNA synthesis. Two type 1 human isolates did not inhibit L cell DNA synthesis, whereas, three type 3 isolates (two bovine and one mouse) did inhibit L cell DNA synthesis (Sharpe and Fields, 1981). Thus, the capacity of type 3 reovirus to inhibit DNA synthesis is a serotype-specific property and not just peculiar to the laboratory strain of reovirus type 3 Dearing. This finding is consistent with the identification of the SI gene product as the determinant of serotype specificity (Weiner et al., 1977, 1978). 

With respect to cellular RNA synthesis, virtually no inhibition of host transcription has been observed following the infection of L cells with reovirus type 3 (Gomatos and Tamm, 1963 Kudo and Graham, 1965 Sharpe and Fields, 1982). Host mRNAs are present in type 3 reovirus-infected L cells late in the infectious cycle, although they are not translated, indicating host mRNA stability in the infected cell (Skup et ai, 1981). If the mechanism of reovirus inhibition of cellular protein synthesis does indeed involve a shift of the host translational machinery from cap dependence to cap independence, then the inhibition of protein synthesis does not require that reovirus induce an inhibition of host mRNA synthesis since all host mRNAs are capped. 

Fig. 4. Reovirus-infected monkey kidney CV-1 cells at 48 hr postinfection with reovirus type 3. Cells were stained with rabbit antireovirus serum and fluorescein-conjugated goat and rabbit serum according to the method of Sharpe et al. (1982). Cytoplasmic inclusions are represented by the numerous globular white areas within the cytoplasm. Note the gradation of size of inclusions, from small to large, as the inclusions approach the nucleus (bar = 20 fxm). From Sharpe et al. (1982), by permission of Virology.

Fields, B. N., Raine, C. S., and Baum, S. G., 1971, Temperature-sensitive mutants of reovirus type 3 Defects in viral maturation as studied by immunofluorescence and electron microscopy. Virology 43 569. 

Gomatos, P. J., Tamm, I., Dales, S., and Franklin, R. M., 1962, Reovirus type 3 Physical characteristics and interaction with L cells. Virology 17 441. 

McCrae, M. A., and Joklik, W. K., 1978, The nature of the polypeptide encoded by each of the 10 double-stranded RNA segments of reovirus type 3, Virology 89 578. 

Stanley, N. F., and Joske, R. A., 1975a, Animal model Chronic murine hepatitis induced by reovirus type 3, Am. J. Pathol. 80 181. 

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