Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Purification and some properties of a protein factor binding and deacylating initiator transfer ribonucleic acid.

ABSTRACT: 1. A protein factor promoting the binding of initiator tRNA to the 40S ribosomal subunit was purified to homogeneity (more than 2500-fold) from rat liver cytosol. It has a mol.wt. of 265000 and is composed of four subunits of identical molecular weight. 2. This factor directs the binding of methionyl-tRNA(fMet) and to a lesser extent also of N-acetylphenylalanyl-tRNA, but not of methionyl-tRNA(Met) or phenylalanyl-tRNA, to the smaller ribosomal subunit at high concentrations of GTP (8-10mm) with an optimum at pH4.0. As evidenced by sucrose-density-gradient centrifugation, initiator tRNA becomes bound to the 40S subunit or to 80S ribosomes. 3. A deacylase activity specific for methionyl-tRNA(fMet) is associated with the pure factor. The factor significantly stimulates the translation of natural message in systems containing polyribosomes and both purified peptide-elongation factors. 4. The factor binds initiator tRNA or GTP to form unstable binary complexes and forms a ternary complex with methionyl-tRNA(fMet) and GTP. This complex is relatively stable. 5. In the absence of any cofactors the factor forms a stable complex with 40S and 80S ribosomes. This preformed ribosomal complex binds efficiently initiator tRNA at pH7.5 and low concentrations of GTP (1-2mm). The ternary complex of the factor with methionyl-tRNA(fMet) and GTP may be liberated from this ribosomal complex. 6. A protein factor capable of promoting the binding and simultaneously the deacylation of initiator tRNA may apparently have a regulatory function in physiological gene translation by removing an excess of methionyl-tRNA(fMet) not required for translation.

SUBMITTER: Pohlreich P

PROVIDER: S-EPMC1186423 | biostudies-other | 1979 Feb

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Purification and properties of methionyl-transfer-ribonucleic acid synthetase from Escherichia coli.

Project description:1. Methionyl-t-RNA synthetase (where t-RNA denotes ;soluble' or transfer RNA) has been purified to apparent homogeneity from a ribonuclease I-free strain of Escherichia coli. Polyacrylamide-gel electrophoresis of the final product revealed a single band. The purified enzyme catalyses the exchange of 450mumoles of pyrophosphate into ATP/mg. in 15min. at 37 degrees . 2. Methionyl-t-RNA synthetase is specific for the l-isomer of methionine, but appears to catalyse the methionylation of two distinct species of t-RNA, both of which are specific for methionine, but only one of which may be subsequently formylated. 3. The Michaelis constant for l-methionine is 2x10(-4)m in the ATP-PP(i) exchange assay and 2x10(-5)m for the acylation of t-RNA. 4. Gel filtration of both crude and highly purified preparations of methionyl-t-RNA synthetase on Sephadex G-200 indicates that the active species of enzyme has a molecular weight of about 190000. The amino acid composition of the enzyme is similar to those reported for the isoleucine and tyrosine enzymes from E. coli.

| S-EPMC1198268 | biostudies-other

Mutations in ribonucleic acid binding protein gene cause familial dilated cardiomyopathy.

Project description:We sought to identify a novel gene for dilated cardiomyopathy (DCM).DCM is a heritable, genetically heterogeneous disorder that remains idiopathic in the majority of patients. Familial cases provide an opportunity to discover unsuspected molecular bases of DCM, enabling pre-clinical risk detection.Two large families with autosomal-dominant DCM were studied. Genome-wide linkage analysis was used to identify a disease locus, followed by fine mapping and positional candidate gene sequencing. Mutation scanning was then performed in 278 unrelated subjects with idiopathic DCM, prospectively identified at the Mayo Clinic.Overlapping loci for DCM were independently mapped to chromosome 10q25-q26. Deoxyribonucleic acid sequencing of affected individuals in each family revealed distinct heterozygous missense mutations in exon 9 of RBM20, encoding ribonucleic acid (RNA) binding motif protein 20. Comprehensive coding sequence analyses identified missense mutations clustered within this same exon in 6 additional DCM families. Mutations segregated with DCM (peak composite logarithm of the odds score >11.49), were absent in 480 control samples, and altered residues within a highly conserved arginine/serine (RS)-rich region. Expression of RBM20 messenger RNA was confirmed in human heart tissue.Our findings establish RBM20 as a DCM gene and reveal a mutation hotspot in the RS domain. RBM20 is preferentially expressed in the heart and encodes motifs prototypical of spliceosome proteins that regulate alternative pre-messenger RNA splicing, thus implicating a functionally distinct gene in human cardiomyopathy. RBM20 mutations are associated with young age at diagnosis, end-stage heart failure, and high mortality.

| S-EPMC2782634 | biostudies-literature

The purification and properties of the alanyl-transfer ribonucleic acid synthetase of tomato roots.

Project description:1. The alanyl-s-RNA synthetase of tomato roots has been purified by ammonium sulphate precipitation, adsorption on calcium phosphate gel and DEAE-cellulose chromatography and its properties have been investigated. 2. Enzyme activity was measured by using the hydroxamate assay, the [(32)P]pyrophosphate-ATP-exchange assay and the [(14)C]alanyl-s-RNA assay. The purified enzyme was specific for l-alanine and was activated by Mg(2+) ions and to a smaller extent by Co(2+) and Mn(2+) ions. It was free from adenosine triphosphatase, pyrophosphatase and ribonuclease, and possessed a specific activity comparable with that of the most highly purified aminoacyl-s-RNA synthetases from animal and microbial systems. 3. The properties of the purified enzyme were similar in many respects to most other highly purified aminoacyl-s-RNA synthetases. It differed, however, in that the pH optimum of the hydroxamate assay was almost the same as that of the pyrophosphate-ATP-exchange assay and in requiring a high concentration of l-alanine for maximum activity (100mumoles/ml.). 4. The purified enzyme was not absolutely specific for tomato-root s-RNA; slight activity was also observed with yeast s-RNA. 5. The properties of this enzyme are fully consistent with the suggestion that the enzymic formation of alanyl-s-RNA proceeds via the intermediate formation of alanyl acyl-adenylate with the elimination of pyrophosphate from ATP. It remains to be shown the extent to which alanyl-s-RNA participates further in subsequent stages of protein synthesis in plants.

| S-EPMC1207195 | biostudies-other

Linking spermatid ribonucleic acid (RNA) binding protein and retrogene diversity to reproductive success.

Project description:Spermiogenesis is a postmeiotic process that drives development of round spermatids into fully elongated spermatozoa. Spermatid elongation is largely controlled post-transcriptionally after global silencing of mRNA synthesis from the haploid genome. Here, rats that differentially express EGFP from a lentiviral transgene during early and late steps of spermiogenesis were used to flow sort fractions of round and elongating spermatids. Mass-spectral analysis of 2D gel protein spots enriched >3-fold in each fraction revealed a heterogeneous RNA binding proteome (hnRNPA2/b1, hnRNPA3, hnRPDL, hnRNPK, hnRNPL, hnRNPM, PABPC1, PABPC4, PCBP1, PCBP3, PTBP2, PSIP1, RGSL1, RUVBL2, SARNP2, TDRD6, TDRD7) abundantly expressed in round spermatids prior to their elongation. Notably, each protein within this ontology cluster regulates alternative splicing, sub-cellular transport, degradation and/or translational repression of mRNAs. In contrast, elongating spermatid fractions were enriched with glycolytic enzymes, redox enzymes and protein synthesis factors. Retrogene-encoded proteins were over-represented among the most abundant elongating spermatid factors identified. Consistent with these biochemical activities, plus corresponding histological profiles, the identified RNA processing factors are predicted to collectively drive post-transcriptional expression of an alternative exome that fuels finishing steps of sperm maturation and fitness.

| S-EPMC3820935 | biostudies-literature

Intermediate reactions in the binding of aminoacyl-transfer ribonucleic acid to rat liver ribosomes. Formation and properties of an aminoacyl-transfer ribonucleic acid-transferase I complex.

Project description:1. Transferase I of rat liver binds aminoacyl-tRNA to form a relatively stable complex, which is retained on cellulose nitrate filters. This reaction proceeds at both 0 degrees C and 37 degrees C and is inhibited by GTP. The resulting product is stabilized by GTP and Mg(2+). 2. Only very low quantities of deacylated tRNA are bound by transferase I. 3. Methods are described for the preparative isolation of the transferase I-aminoacyl-tRNA complex from incubation mixtures by using ion-exchange procedures. 4. The transferase I-aminoacyl-tRNA complex becomes readily bound to ribosomes. The presence of Mg(2+) is essential for the binding. GTP stimulates this reaction but is not absolutely required. 5. It is concluded that the formation of the transferase I-aminoacyl-tRNA complex may be the primary reaction in the binding of aminoacyl-tRNA to mammalian ribosomes and that, unlike in bacterial systems, GTP is not absolutely required for this step.

| S-EPMC1178500 | biostudies-other

Short hairpin ribonucleic acid constructs targeting insulin-like growth factor binding protein-3 rehabilitated decreased testosterone concentrations in diabetic rats.

Project description:The aim of this study was to determine if shRNA constructs targeting insulin-like growth factor binding protein-3 can rehabilitate decreased serum testosterone concentrations in streptozotocin-induced diabetic rats.After 12 weeks of intracavernous administration of IGFBP-3 shRNA, intracavernous pressure responses to electrical stimulation of cavernous nerves were evaluated. The expression of IGFBP-3 at mRNA and protein levels was detected by quantitative real-time PCR analysis and Western blot, respectively. The concentrations of serum testosterone and cavernous cyclic guanosine monophosphate were detected by enzyme-linked immunosorbent assay.After 12 weeks of intracavernous administration of IGFBP-3 shRNA, the cavernosal pressure was significantly increased in response to the cavernous nerves stimulation compared to the diabetic control group (p<0.01). Cavernous IGFBP-3 expression at both mRNA and protein levels was significantly inhibited. Both serum testosterone and cavernous cyclic guanosine monophosphate concentrations were significantly increased in the IGFBP-3 shRNA treatment group compared to the diabetic control group (p<0.01).These results suggest that IGFBP-3 shRNA may rehabilitate erectile function via increases of concentrations of serum testosterone and cavernous cyclic guanosine monophosphate in streptozotocin-induced diabetic rats.

| S-EPMC4289482 | biostudies-literature

Studies on the fractionation of total transfer ribonucleic acid and purification of an alanine transfer ribonucleic acid from chick embryo.

Project description:Chick embryo tRNA, prepared by a simple large-scale method, was fractionated on three different ion-exchange columns. In all cases simple chromatographic patterns for various tRNA species were observed, indicating the presence of only a few major species of tRNA for each amino acid. By repeated chromatography one species of alanine tRNA was purified to approx. 80% purity. T(1) ribonuclease digest of this purified tRNA gave a simple chromatographic pattern. Because of the simplicity of the method of preparation of tRNA from this readily available source and the presence of only a few species of tRNA for each amino acid, chick embryo is suited for the study of tRNA and its various functions in higher systems.

| S-EPMC1168169 | biostudies-other

Purification and properties of the ribonucleic acid-dependent ribonucleic acid polymerase from Halobacterium cutirubrum.

Project description:1. The RNA-dependent RNA polymerase from Halobacterium cutirubrum was purified to electrophoretic homogeneity. 2. It requires a single-stranded molecule of RNA or polyribonucleotide as template. 3. Nearest-neighbour analyses of the products formed on random poly(A,U) or alternating poly(A-U) templates and base analysis of the product of synthesis directed by wheat-germ RNA prove that the template is copied accurately. 4. The enzyme initiates new chains with purine ribonucleoside triphosphates. 5. Sucrose-density-gradient analysis of the product indicates that it has a size distribution similar to that of the template. 6. Preliminary amino acid analysis of the RNA-dependent polymerase shows that it contains much less serine than either of the subunits of H. cutirubrum DNA-dependent RNA polymerase. 7. The RNA-dependent enzyme is unable to substitute for either subunit of the DNA-dependent polymerase, and both the latter are devoid of RNA-dependent activity.

| S-EPMC1173895 | biostudies-other

The ribosomal binding site for peptidyl-transfer-ribonucleic acid.

Project description:The properties of a site, on Escherichia coli ribosomes, which binds peptidyl-s-RNA (where s-RNA refers to ;soluble' or transfer RNA) have been investigated. The binding is stable both in low Mg(2+) concentration (0.1mm), and in high Mg(2+) concentration (10mm) in the absence or presence of potassium chloride (86mm). Puromycin has been used to break the bond between the s-RNA and the polypeptide, and in the absence of further protein synthesis this technique exposes free s-RNA molecules on the ribosomes. The s-RNA exposed remains bound in high Mg(2+) concentration, but the binding is unstable in high Mg(2+) concentration with potassium chloride and the s-RNA can be freed completely from the ribosomes by lowering the Mg(2+) concentration. It can also be displaced by s-RNA in the medium. It is suggested that this ribosomal binding site for peptidyl-s-RNA is the site for peptide bond formation. Further, it is proposed that it is the same site that can be demonstrated on ribosomes not engaged in protein synthesis and that, in high Mg(2+) concentration, will bind s-RNA molecules charged or uncharged with amino acids.

| S-EPMC1271235 | biostudies-other

Purification and properties of a nuclear protein kinase associated with ribonucleic acid polymerase I.

Project description:A cyclic AMP-dependent nuclear protein kinase was found to be closely associated with rat liver nucleolar RNA polymerase I throughout most of its purification. This protein kinase was purified to near homogeneity. It exhibits a number of unusual catalytic properties, including the inability to utilize Mn2+ when RNA polymerase is the substrate and the ability to phosphorylate both acidic and basic substrates. Phosphorylation of RNA polymerase I by this protein kinase results in the formation of phosphoester bonds characteristic of phosphoserine and phosphothreonine. Radioautography of polyacrylamide-gel electrophoretograms of the phosphorylated RNA polymerase I revealed that the 32P was located primarily on enzyme subunits SA1, SA3, SA5, and SA6 [nomenclature of Kedinger, Gissinger & Chambon (1974) Eur. J. Biochem, 44, 421-436].

| S-EPMC1184174 | biostudies-other

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