The sigma 1 protein determines the extent of spread of reovirus from the gastrointestinal tract of mice.
After intragastric inoculation of adult mice, type 1 reovirus was initially concentrated in Peyer's patches over the first 4 hr after inoculation, then spread sequentially to the mesenteric lymph nodes and spleen. For type 3 reovirus, however, initial entry into Peyer's patches in adult mice was followed by loss of viral infectivity so that by 4 hr after inoculation virtually no infectious virus was detected in the intestine, and spread to extraintestinal tissues did not occur. In 10-day-old mice, type 3 was capable of spread to the mesenteric lymph nodes but not the spleen. Thus, as animals aged there was a greater restriction of the spread of type 3 from the intestine. Studies using a field isolate of type 3 reovirus that is resistant to intestinal proteases, and genetic studies utilizing type 1 x type 3 viral reassortants, revealed that the viral sigma 1 protein determined the capacity of reovirus to spread from the intestine in both adult and 10-day-old mice. Thus, the interaction of reovirus with host defense mechanisms, and the age-dependent restriction of spread of type 3 reovirus from the intestine are mediated by the viral sigma 1 protein.
D000375:Aging; D000818:Animals; D000833:Animals, Suckling; D002213:Capsid / Q000502:physiology; D006389:Hemagglutinins, Viral; D007422:Intestines / Q000382:microbiology*; D008198:Lymph Nodes / Q000382:microbiology*; D012089:Mammalian orthoreovirus 3 / Q000472:pathogenicity; D051379:Mice; D008809:Mice, Inbred C3H; D010581:Peyer's Patches / Q000382:microbiology; D012087:Reoviridae / Q000472:pathogenicity*; D013154:Spleen / Q000382:microbiology*; D014764:Viral Proteins / Q000502:physiology
D006389:Hemagglutinins, Viral; D014764:Viral Proteins