Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Deletions at the C-terminus of interferon gamma reduce RNA binding and activation of double-stranded-RNA cleavage by bovine seminal ribonuclease.

ABSTRACT: Recombinant interferon gamma (IFN-gamma) from three species activates the cleavage of double stranded (ds-) RNA by the dimeric RNAase isolated from bovine semen (BS-RNAase). Human and bovine IFN-gamma bind RNA tightly enough to inhibit cleavage by RNAase A [Schein, Haugg and Benner (1990) FEBS Lett. 270, 229-232]. Murine IFN-gamma and a proteolytic fragment of human IFN-gamma, both of which lack part of the positively charged C-terminus, bind RNA weakly and do not inhibit RNAase A. Their ability to activate BS-RNAase is proportional to their activity in the anti-viral assay. Two monoclonal antibodies that neutralize the anti-viral activity of human IFN-gamma inhibit the activation of BS-RNAase by both full-length and proteolysed human IFN-gamma. Our results demonstrate that the C-terminus of IFN-gamma contributes to RNA binding and activation of BS-RNAase, as well as to anti-viral activity.

SUBMITTER: Schein CH

PROVIDER: S-EPMC1136753 | biostudies-other | 1995 Apr

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Ribonuclease III mechanisms of double-stranded RNA cleavage.

Project description:Double-stranded(ds) RNA has diverse roles in gene expression and regulation, host defense, and genome surveillance in bacterial and eukaryotic cells. A central aspect of dsRNA function is its selective recognition and cleavage by members of the ribonuclease III (RNase III) family of divalent-metal-ion-dependent phosphodiesterases. The processing of dsRNA by RNase III family members is an essential step in the maturation and decay of coding and noncoding RNAs, including miRNAs and siRNAs. RNase III, as first purified from Escherichia coli, has served as a biochemically well-characterized prototype, and other bacterial orthologs provided the first structural information. RNase III family members share a unique fold (RNase III domain) that can dimerize to form a structure that binds dsRNA and cleaves phosphodiesters on each strand, providing the characteristic 2 nt, 3'-overhang product ends. Ongoing studies are uncovering the functions of additional domains, including, inter alia, the dsRNA-binding and PAZ domains that cooperate with the RNase III domain to select target sites, regulate activity, confer processivity, and support the recognition of structurally diverse substrates. RNase III enzymes function in multicomponent assemblies that are regulated by diverse inputs, and at least one RNase III-related polypeptide can function as a noncatalytic, dsRNA-binding protein. This review summarizes the current knowledge of the mechanisms of catalysis and target site selection of RNase III family members, and also addresses less well understood aspects of these enzymes and their interactions with dsRNA.

| S-EPMC3867540 | biostudies-literature

Functional role of glutamine 28 and arginine 39 in double stranded RNA cleavage by human pancreatic ribonuclease.

Project description:Human pancreatic ribonuclease (HPR), a member of RNase A superfamily, has a high activity on double stranded (ds) RNA. By virtue of this activity HPR appears to be involved in the host-defense against pathogenic viruses. To delineate the mechanism of dsRNA cleavage by HPR, we have investigated the role of glutamine 28 and arginine 39 of HPR in its activity on dsRNA. A non-basic residue glycine 38, earlier shown to be important for dsRNA cleavage by HPR was also included in the study in the context of glutamine 28 and arginine 39. Nine variants of HPR respectively containing Q28A, Q28L, R39A, G38D, Q28A/R39A, Q28L/R39A, Q28A/G38D, R39A/G38D and Q28A/G38D/R39A mutations were generated and functionally characterized. The far-UV CD-spectral analysis revealed all variants, except R39A, to have structures similar to that of HPR. The catalytic activity of all HPR variants on single stranded RNA substrate was similar to that of HPR, whereas on dsRNA, the catalytic efficiency of all single residue variants, except for the Q28L, was significantly reduced. The dsRNA cleavage activity of R39A/G38D and Q28A/G38D/R39A variants was most drastically reduced to 4% of that of HPR. The variants having reduced dsRNA cleavage activity also had reduction in their dsDNA melting activity and thermal stability. Our results indicate that in HPR both glutamine 28 and arginine 39 are important for the cleavage of dsRNA. Although these residues are not directly involved in catalysis, both arginine 39 and glutamine 28 appear to be facilitating a productive substrate-enzyme interaction during the dsRNA cleavage by HPR.

| S-EPMC3050822 | biostudies-literature

Identification of double-stranded RNA-binding domains in the interferon-induced double-stranded RNA-activated p68 kinase.

Project description:The double-stranded RNA (dsRNA)-binding domain of the human p68 kinase has been localized to the N-terminal half of the enzyme by using progressive deletion analysis and in vitro binding assays. To further define the domains responsible for binding to dsRNA, we cloned the mouse dsRNA-activated p65 kinase and used sequence alignment to identify conserved domains in the N-terminal region. Deletions in either of two 12-amino-acid-long and arginine- or lysine-rich regions abrogated binding to dsRNA. Moreover, in an in vivo growth inhibition assay in the yeast Saccharomyces cerevisiae, these mutants failed to exhibit a slow-growth phenotype.

| S-EPMC49309 | biostudies-other

Pellino1 is required for interferon production by viral double-stranded RNA.

Project description:Viral double-stranded RNA, a ligand for Toll-like Receptor 3 (TLR3) and the cytoplasmic RNA receptors RIG1 and MDA5, activate a signaling network in which the IKK-related protein kinase TBK1 phosphorylates the transcription factor Interferon Regulatory Factor 3 (IRF3) and the E3 ubiquitin ligase Pellino1. IRF3 then translocates to the nucleus where it stimulates transcription of the interferon? (IFN?) gene, but the function of Pellino1 in this pathway is unknown. Here, we report that myeloid cells and embryonic fibroblasts from knock-in mice expressing an E3 ligase-deficient mutant of Pellino1 produce reduced levels of IFN? mRNA and secrete much less IFN? in response to viral double-stranded RNA because the interaction of IRF3 with the IFN? promoter is impaired. These results identify Pellino1 as a novel component of the signal transduction network by which viral double-stranded RNA stimulates IFN? gene transcription.

| S-EPMC3464584 | biostudies-literature

Ebolavirus VP35 coats the backbone of double-stranded RNA for interferon antagonism.

Project description:Recognition of viral double-stranded RNA (dsRNA) activates interferon production and immune signaling in host cells. Crystal structures of ebolavirus VP35 show that it caps dsRNA ends to prevent sensing by pattern recognition receptors such as RIG-I. In contrast, structures of marburgvirus VP35 show that it primarily coats the dsRNA backbone. Here, we demonstrate that ebolavirus VP35 also coats the dsRNA backbone in solution, although binding to the dsRNA ends probably constitutes the initial binding event.

| S-EPMC3753998 | biostudies-literature

Single-molecule analysis of processive double-stranded RNA cleavage by Drosophila Dicer-2.

Project description:Drosophila Dicer-2 (Dcr-2) produces small interfering RNAs from long double-stranded RNAs (dsRNAs), playing an essential role in antiviral RNA interference. The dicing reaction by Dcr-2 is enhanced by Loquacious-PD (Loqs-PD), a dsRNA-binding protein that partners with Dcr-2. Previous biochemical analyses have proposed that Dcr-2 uses two distinct-processive or distributive-modes of cleavage by distinguishing the terminal structures of dsRNAs and that Loqs-PD alters the terminal dependence of Dcr-2. However, the direct evidence for this model is lacking, as the dynamic movement of Dcr-2 along dsRNAs has not been traced. Here, by utilizing single-molecule imaging, we show that the terminal structures of long dsRNAs and the presence or absence of Loqs-PD do not essentially change Dcr-2's cleavage mode between processive and distributive, but rather simply affect the probability for Dcr-2 to undergo the cleavage reaction. Our results provide a refined model for how the dicing reaction by Dcr-2 is regulated.

| S-EPMC8277814 | biostudies-literature

Mechanism of interferon action: functionally distinct RNA-binding and catalytic domains in the interferon-inducible, double-stranded RNA-specific adenosine deaminase.

Project description:The 1,226-amino-acid sequence of the interferon-inducible double-stranded RNA-specific adenosine deaminase (dsRAD) contains three copies (RI, RII, and RIII) of the highly conserved subdomain R motif commonly found in double-stranded RNA-binding proteins. We have examined the effects of equivalent site-directed mutations in each of the three R-motif copies of dsRAD on RNA-binding activity and adenosine deaminase enzyme activity. Mutations of the R motifs were analyzed alone as single mutants and in combination with each other. The results suggest that the RIII copy is the most important of the three R motifs for dsRAD activity and that the RII copy is the least important. The RIII mutant lacked detectable enzymatic activity and displayed greatly diminished RNA-binding activity. Site-directed mutations within the highly conserved CHAE sequence of the postulated C-terminal deaminase catalytic domain destroyed enzymatic activity but did not affect RNA-binding activity. These results indicate that the three copies of the RNA-binding R subdomain are likely functionally distinct from each other and also from the catalytic domain of dsRAD.

| S-EPMC190025 | biostudies-other

Cleavage of double-stranded RNA by RNase HI from a thermoacidophilic archaeon, Sulfolobus tokodaii 7.

Project description:ST0753, the orthologous gene of Type 1 RNase H found in a thermoacidophilic archaeon, Sulfolobus tokodaii, was analyzed. The recombinant ST0753 protein exhibited RNase H activity in both in vivo and in vitro assays. The protein expressed in an RNase H-deficient mutant Escherichia coli strain functioned to suppress the temperature-sensitive phenotype associated with the lack of RNase H. The in vitro characteristics of the gene's RNase H activity were similar to those of Halobacterium RNase HI, the first archaeal Type 1 RNase H to be characterized. Surprisingly, the S.tokodaii RNase HI cleaved not only the RNA strand of an RNA/DNA hybrid but also an RNA strand of an RNA/RNA duplex in the presence of Mn2+ or Co2+. The result of gel filtration column chromatography showed this double-stranded RNA-dependent RNase (dsRNase) activity was coincident with S.tokodaii RNase HI. A site-directed mutagenesis study of essential amino acids for RNase H activity indicated that this activity also affected dsRNase activity. A single amino acid replacement of Asp-125 by Asn resulted in loss of dsRNase activity but not RNase H activity, suggesting that amino acid residues required for dsRNase activity seemed slightly different from those of RNase H activity. Some reverse transcriptases from retroelements can cleave double-stranded RNA, and this activity requires the RNase H domain. Similarities in primary structure and biochemical characteristics between S.tokodaii RNase HI and reverse transcriptases imply that the S.tokodaii enzyme might be derived from the RNase H domain of reverse transcriptase.

| S-EPMC528802 | biostudies-other

Inactivation of the type I interferon pathway reveals long double-stranded RNA-mediated RNA interference in mammalian cells.

Project description:RNA interference (RNAi) elicited by long double-stranded (ds) or base-paired viral RNA constitutes the major mechanism of antiviral defence in plants and invertebrates. In contrast, it is controversial whether it acts in chordates. Rather, in vertebrates, viral RNAs induce a distinct defence system known as the interferon (IFN) response. Here, we tested the possibility that the IFN response masks or inhibits antiviral RNAi in mammalian cells. Consistent with that notion, we find that sequence-specific gene silencing can be triggered by long dsRNAs in differentiated mouse cells rendered deficient in components of the IFN pathway. This unveiled response is dependent on the canonical RNAi machinery and is lost upon treatment of IFN-responsive cells with type I IFN Notably, transfection with long dsRNA specifically vaccinates IFN-deficient cells against infection with viruses bearing a homologous sequence. Thus, our data reveal that RNAi constitutes an ancient antiviral strategy conserved from plants to mammals that precedes but has not been superseded by vertebrate evolution of the IFN system.

| S-EPMC5167344 | biostudies-other

Analysis of double-stranded RNA from microbial communities identifies double-stranded RNA virus-like elements.

Project description:Double-stranded RNA (dsRNA) can function as genetic information and may have served as genomic material before the existence of DNA-based life. By developing a method to purify dsRNA, we have investigated the diversity of dsRNA in microbial populations. We detect large dsRNAs in multiple microbial populations. Analysis of an aquatic microbial population reveals that some dsRNA sequences match metagenomic DNA, suggesting that microbes contain pools of sense-antisense transcripts. In addition, ?30% of the dsRNA sequences are not present in the corresponding DNA pool and are strongly biased toward encoding novel proteins. Of these "dsRNA unique" sequences, only a small percentage share similarity to known viruses, a large fraction assemble into RNA virus-like contigs, and the remaining fraction has an unexplained origin. These results have uncovered dsRNA virus-like elements and underscore that dsRNA potentially represents an additional reservoir of genetic information in microbial populations.

| S-EPMC4117469 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data