Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.1.4 (deaminase)
 5,113 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
 ...
PMID:Mechanism of interferon action: functionally distinct RNA-binding and catalytic domains in the interferon-inducible, double-stranded RNA-specific adenosine deaminase. 862 22

RNAs encoding subunits of glutamate-gated ion channel receptors are posttranscriptionally modified by RNA editing and alternative splicing. The change in amino acid sequence caused by RNA editing can affect both the kinetics and the permeability of the ion channel receptors to cations. Here, we report the purification of a 90-kDa double-stranded RNA-specific adenosine deaminase from HeLa cell nuclear extract that specifically edits the glutamine codon at position 586 in the pre-mRNA of the glutamate receptor B subunit. Site-specific deamination of an adenosine to an inosine converts the glutamine codon to that of arginine. Recently, a gene encoding a double-stranded-specific editase (RED1) was cloned from a rat brain cDNA library. Antibodies generated against the deaminase domain of its human homolog specifically recognized and inhibited the activity of the 90-kDa enzyme, indicating that we have purified hRED1 the human homolog of rat RED1. This enzyme is distinct from double-stranded RNA-specific adenosine deaminase which we and others have previously purified and cloned.
 ...
PMID:Purification of human double-stranded RNA-specific editase 1 (hRED1) involved in editing of brain glutamate receptor B pre-mRNA. 899 85

The past year has witnessed major progress in the field of mammalian nuclear RNA editing. Two new sequence-related RNA-dependent adenosine deaminases, distantly related to the previously characterized double-stranded RNA adenosine deaminase DRADA/dsRAD, have been molecularly characterized. One of these deaminases edits in vitro with precision for the molecular determinant that controls the Ca2+ permeability of fast synaptic glutamate-gated cation channels. This deaminase, like DRADA, is expressed in many tissues and the search is now on for more substrates of these RNA-editing enzymes. Moreover, the physiological role of the apolipoprotein B RNA editing enzyme APOBEC-1 has been investigated in genetically manipulated mice.
 ...
PMID:Mammalian RNA-dependent deaminases and edited mRNAs. 915 72

Dyschromatosis symmetrica hereditaria (OMIM127400) is a rare autosomal dominant pigmentary genodermatosis caused by mutations in the RNA-specific adenosine deaminase (ADAR) gene. This study investigated 5 families and 3 sporadic patients with dyschromatosis symmetrica hereditaria in the Chinese Han population from Anhui province, China. By direct sequencing, 5 novel ADAR gene mutations (c.982C>T, c.1491insA, c.2568_2571delTAAC, c.2969C>G and c.3040G>T) and 3 mutations described previously (c.3203-2A>G, c.3247C>T and c.3286C>T) were identified, all of which were heterozygous. We reviewed a total of 48 mutations in the ADAR gene in patients with dyschromatosis symmetrica hereditaria by previous reports and speculated that the mutation hotspots on the ADAR gene might be located in exons 9-15. The tRNA-specific and double-stranded RNA adenosine deaminase domain is essential for the deaminase activity of the ADAR encoded protein.
 ...
PMID:Five novel mutations of RNA-specific adenosine deaminase gene with dyschromatosis symmetrica hereditaria. 1722 10

ADAR2 is a double-stranded RNA-specific adenosine deaminase involved in the editing of mammalian RNAs by the site-specific conversion of adenosine to inosine. To examine the physiologic consequences resulting from ADAR2 misexpression, we have generated mutant mice expressing either wild-type or deaminase-deficient ADAR2 transgenes under the control of the human cytomegalovirus promoter. Transgenic mice expressing either wild-type or inactive ADAR2 isoforms demonstrated adult onset obesity characterized by hyperglycemia, hyperleptinemia, and increased adiposity. Paired feeding analysis revealed that mutant mice on caloric restriction had a growth rate and body composition indistinguishable from wild-type littermates, indicating that the observed obesity predominantly results from hyperphagia rather than a metabolic derangement. The observation that expression of catalytically inactive ADAR2 also is capable of producing an obese phenotype in mutant animals suggests that ADAR2 may possess additional biological activities beyond those required for the site-selective deamination of adenosine or may interfere with the actions of other double-stranded RNA-specific binding proteins in the cell.
 ...
PMID:Hyperphagia-mediated obesity in transgenic mice misexpressing the RNA-editing enzyme ADAR2. 1756 73

Dyschromatosis symmetrica hereditaria (DSH) is a rare autosomal dominant cutaneous disorder characterized by a mixture of hyperpigmented and hypopigmented macules of various sizes on the limbs. Genetic studies have identified mutations in the DSRAD gene, encoding double-stranded RNA-specific adenosine deaminase, to be responsible for this disorder. In this study, we identified a novel mutation of DSRAD gene in a Chinese family with DSH. The mutation is a novel heterozygous nucleotide T-->C transition at position 3617 in exon 15 of the DSRAD gene, which induces a M1206T change in the putative deaminase domain of DSRAD. Our study expands the database on the DSRAD gene mutations in DSH.
 ...
PMID:Identification of a novel DSRAD gene mutation in a Chinese family with dyschromatosis symmetrica hereditaria. 1862 85