Biomaterial Database

Two basic motifs of reovirus sigma 3 protein are involved in double-stranded RNA binding. 1995

T Mabrouk, and C Danis, and G Lemay

Département de microbiologie et immunologie, Université de Montréal, Canada.

It has been reported that the sigma 3 protein of reovirus can exert an inhibitory effect on the cellular double-stranded RNA (dsRNA) activated protein kinase. Activation of this kinase is thought to be a general mechanism mediating a cellular antiviral response. This enzyme can also be activated upon transfection, resulting in translational inhibition of plasmid-encoded mRNAs. sigma 3 has an affinity for dsRNA postulated to be responsible for antikinase activity. In the present study, site-directed mutagenesis was performed on two basic regions previously suggested as dsRNA-binding motifs and the mutant sigma 3 proteins were then expressed in COS cells. These experiments revealed that both motifs are involved in sigma 3 attachment to RNA. Expression of the mutants lacking RNA-binding capability is stimulated by coexpression of another dsRNA-binding protein, the E3L vaccinia virus protein. These results support a model in which the attachment to dsRNA is directly responsible for the trans-stimulating effect of sigma 3 on expression of cotransfected genes.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D012087	Reoviridae	A family of unenveloped RNA viruses with cubic symmetry. The twelve genera include ORTHOREOVIRUS; ORBIVIRUS; COLTIVIRUS; ROTAVIRUS; Aquareovirus, Cypovirus, Phytoreovirus, Fijivirus, Seadornavirus, Idnoreovirus, Mycoreovirus, and Oryzavirus.	Aquareovirus,Cypovirus,Cytoplasmic Polyhedrosis Viruses,Fijivirus,Idnoreovirus,Mycoreovirus,Oryzavirus,Phytoreovirus,Reoviruses, Aquatic,Respiratory Enteric Orphan Viruses,Seadornavirus,Aquareoviruses,Aquatic Reovirus,Aquatic Reoviruses,Cypoviruses,Cytoplasmic Polyhedrosis Virus,Fijiviruses,Idnoreoviruses,Mycoreoviruses,Oryzaviruses,Phytoreoviruses,Polyhedrosis Virus, Cytoplasmic,Polyhedrosis Viruses, Cytoplasmic,Reovirus, Aquatic,Seadornaviruses
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D012330	RNA, Double-Stranded	RNA consisting of two strands as opposed to the more prevalent single-stranded RNA. Most of the double-stranded segments are formed from transcription of DNA by intramolecular base-pairing of inverted complementary sequences separated by a single-stranded loop. Some double-stranded segments of RNA are normal in all organisms.	Double-Stranded RNA,Double Stranded RNA,RNA, Double Stranded
D014764	Viral Proteins	Proteins found in any species of virus.	Gene Products, Viral,Viral Gene Products,Viral Gene Proteins,Viral Protein,Protein, Viral,Proteins, Viral
D016297	Mutagenesis, Site-Directed	Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.	Mutagenesis, Oligonucleotide-Directed,Mutagenesis, Site-Specific,Oligonucleotide-Directed Mutagenesis,Site-Directed Mutagenesis,Site-Specific Mutagenesis,Mutageneses, Oligonucleotide-Directed,Mutageneses, Site-Directed,Mutageneses, Site-Specific,Mutagenesis, Oligonucleotide Directed,Mutagenesis, Site Directed,Mutagenesis, Site Specific,Oligonucleotide Directed Mutagenesis,Oligonucleotide-Directed Mutageneses,Site Directed Mutagenesis,Site Specific Mutagenesis,Site-Directed Mutageneses,Site-Specific Mutageneses
D016601	RNA-Binding Proteins	Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.	Double-Stranded RNA-Binding Protein,Double-Stranded RNA-Binding Proteins,ds RNA-Binding Protein,RNA-Binding Protein,ds RNA-Binding Proteins,Double Stranded RNA Binding Protein,Double Stranded RNA Binding Proteins,Protein, Double-Stranded RNA-Binding,Protein, ds RNA-Binding,RNA Binding Protein,RNA Binding Proteins,RNA-Binding Protein, Double-Stranded,RNA-Binding Protein, ds,RNA-Binding Proteins, Double-Stranded,ds RNA Binding Protein
D036022	Capsid Proteins	Proteins that form the CAPSID of VIRUSES.	Procapsid Protein,Procapsid Proteins,Viral Coat Protein,Viral Coat Proteins,Viral V Antigens,Viral V Proteins,Capsid Protein,Viral Outer Coat Protein,Antigens, Viral V,Coat Protein, Viral,V Antigens, Viral,V Proteins, Viral