Cover photograph (Copyright © 2003, American Society for Microbiology. All Rights Reserved.): Immunofluorescence microscopy of a CV-1 cell coexpressing the μNS and σNS nonstructural proteins of mammalian orthoreovirus type 1 Lang. Cells transfected with vectors carrying the genes for μNS and σNS were coimmunostained for μNS (red) and σNS (green), and nuclei were counterstained with 4`,6-diamidino-2-phenylindole (blue). The μNS and σNS proteins colocalize (yellow) in viral factory-like inclusion bodies formed by μNS. (See related article on page 4566.)