Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The metabolism of high-molecular-weight ribonucleic acid including polyadenylated species, in the developing rat brain.

ABSTRACT: High-molecular-weight RNA was isolated from rat brain at various times after the intracranial administration of [32P]Pi. The synthesis of 28S and 18S rRNA could be detected within 1h of the injection of the radioactive precursor and appeared to be more pronounced, relative to other high-molecular-weight RNA, in the brains of older rats compared with those of newborn rats. Polyadenylated RNA, representing most mRNA and their precursors, was isolated by chromatography on oligo(dT)-cellulose. The contribution of this polyadenylated RNA to total RNA synthesis was investigated in the cerebral cortex and the phylogenetically older brain stem at different stages in the development of the rats by using a 5h period of labelling as an arbitrary index of transcription. In the brain stem the proportion of labelled polyadenylated RNA comprised 27-30% of the total RNA. The corresponding values for the cortex decreased from 34% in newborn rats to 23% in 40-150-day-old rats. These data indicated that proportionately more polyadenylated RNA is synthesized in the cortex of the newborn than in the adult rat and that there is a progressive decrease in the synthesis of polyadenylated RNA relative to rRNA during development.

SUBMITTER: Berthold W

PROVIDER: S-EPMC1172732 | biostudies-other | 1976 Feb

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Nucleo-cytoplasmic relationships of high-molecular-weight ribonucleic acid, including polyadenylated species, in the developing rat brain.

Project description:The metabolism of high-molecular-weight RNA in the nuclear and cytoplasmic fractions of newborn and adult rat brain was investigated after the intracranial administration of [32P]Pi. In young brain, a considerable proportion of the newly synthesized radioactive RNA is transferred to the cytoplasm, in contrast with the adult brain, where there appears to be a high intranuclear turnover. Electrophoretic analysis of the newly synthesized RNA showed that processing of the rRNA precursor to yield the 28S and 18S rRNA may be more rapid in the adult than in the young, although most of the adult rRNA in the nucleus is not transferred to the cytoplasm. In young brain, processing is probably tightly coupled to transport of rRNA into the cytoplasm, so that 28S and 18S rRNA are not subjected to possible degradation within the nucleus. Polyadenylated RNA turns over in concert with high-molecular-weight RNA in the nuclei of the adult rat brain. In the cytoplasm the polyadenylated RNA has a higher turnover rate relative to rRNA. In the young brain the polyadenylated RNA is transferred to the cytoplasm along with rRNA, although polyadenylated RNA is transported into the cytoplasm at a faster rate. The nuclear and cytoplasmic polyadenylated RNA species of young brain are larger than their corresponding adult counterparts. These results suggest that there are considerable changes in the regulation of the nucleo-cytoplasmic relationship of rRNA and polyadenylated RNA during the transition of the brain from a developing replicative phase to an adult differentiated and non-dividing state.

| S-EPMC1172733 | biostudies-other

The metabolism of high-molecular-weight ribonucleic acid in hypothalamic and cortical regions of the developing female rat brain.

Project description:The regional metabolism of high-molecular-weight RNA in the developing female rat brain was investigated after the intracranial injection of [32P]P1. The synthesis of polyadenylated RNA relative to high-molecular-weight RNA was determined after oligo(dT)-cellulose chromatography of total cellular high-molecular-weight RNA labelled after 4h. In both hypothalamus and cortex this synthesis was significantly higher during the first 10 days post partum than at subsequent ages. In both regions apparently more mRNA is synthesized in the young. The ratio of the specific radioactivity of cytoplasmic high-molecular-weight RNA relative to that of the nucleus, measured after a 48 h period of labelling, was considered to be an index of the nucleocytoplasmic transport of newly synthesized RNA [Berthold & Lim (1976) Biochem. J. 154, 529--539]. In the cortex, nucleo-cytoplasmic RNA transport in rats aged up to 20 days was significantly higher than in older rats, with the maximal value being attained between 16 and 19 days post partum. In contrast, in the hypothalamus, nucleo-cytoplasmic transport of RNA was low during the neonatal period and comparable with that of the mature animal. However, there were two periods of increased transport at later stages of development, the first between 15 and 19 days post partum and the second between 25 and 29 days post partum. These prepubertal changes in the nucleo-cytoplasmic transport of RNA in the female hypothalamus during weeks 3 and 4 post partum are coincident with other reported changes occurring during sexual differentiation. Differences in the timing of the maturational changes of the two brain regions thus appear to be reflected in developmental changes in RNA transport.

| S-EPMC1186260 | biostudies-other

The fractionation of high-molecular-weight ribonucleic acid by polyacrylamide-gel electrophoresis.

Project description:1. Gels were prepared with recrystallized acrylamide and bisacrylamide. Electrophoresis was in tris-sodium acetate-EDTA buffer for 0.5 to 3hr. Gels were scanned at 280 or 265mmu. Techniques are described for slicing and radioactive counting. 2. The mobility of RNA was inversely related to the sedimentation coefficient and varied with gel concentration. Electrophoresis in 2.2-2.6% gels gives a fractionation similar to density-gradient centrifugation. It shows the two ribosomal RNA components, the 45s precursor, transfer RNA and minor components. In 5% and 7.5% gels, 4s and 5s RNA separated and ribosomal RNA was excluded. 3. The resolution is greater and more detailed than by centrifugation, and many samples can be analysed simultaneously and rapidly.

| S-EPMC1270235 | biostudies-other

Terminal sequence studies of high-molecular-weight ribonucleic acid. The 3' termini of rabbit globin messenger ribonucleic acid.

Project description:Haemoglobin mRNA isolated from EDTA-treated polyribosomes has an apparent molecular weight of 120000-180000 estimated by condensation with (3)H-labelled isoniazid after periodate oxidation. Analysis of the ribonuclease digests of isoniazid-labelled RNA by paper electrophoresis and column chromatography enables the amount of contaminating 18S, 7S, 5S and 4S RNA to be estimated, and a corrected molecular weight of globin mRNA as the acid is 161000 or 500 nucleotides in length. This molecule contains two groups of 3'-terminal sequences in equal yield; G-Y-A(6) and G-Y-A(7) in the ratio 3:2, and G-N(9-16)-Y-A(2) and G-N(9-16)-Y-N(3) in the ratio 3:2. The significance of these sequences is discussed in relation to the poly(A) content of globin mRNA, the specificity of the sequences, and possible function in processing and biosynthesis of mRNA.

| S-EPMC1177471 | biostudies-other

The distribution of individual miRNA species between high-molecular weight and low-molecular weight RISC complexes by small RNA sequencing in thyroid cancer cell lines

Project description:Thyroid cancer is the most prevalent malignancy of the endocrine system. We and others have shown that several microRNAs, which are ~21-24nt post-transcriptional gene regulators, are aberrantly expressed in anaplastic thyroid cancer (ATC) and papillary thyroid cancer (PTC) tissues and cell lines. In the cell, miRNAs are bound to Argonaute (AGO) proteins as low molecular weight RNA Induced Silencing Complexes (LMW-RISCs) that can then assemble into high molecular weight RISCs (HMW-RISCs) that also include additional proteins and mRNA. In this study, we sought to analyze the association of miRNAs across RISC complexity in ATC and PTC. For both ATC and PTC lines, miRNAs were enriched in HMW-RISC and LMW-RISC fractions compared with intermediate fractions or very low molecular weight (AGO-poor) fractions. Furthermore, 60% of all miRNAs were more abundant in LMW-RISC versus HMW- RISC fractions by ~2-4 fold. Surprisingly, miR-21-5p, one of the most abundant miRNAs in both ATC and PTC lines, was consistently one the least abundant miRNAs in HMW-RISC and the most enriched miRNA in LMW-RISC fractions. These findings suggest that miR-21 may be uniquely distributed in RISCs relative to other miRNAs. Furthermore, the methodology described here is a useful way to assess the relative magnitude of miR-21association with HMW and LMW-RISCs and may help to reveal the true roles of this miRNA in thyroid cancer development, progression, and treatment.

2020-02-28 | GSE146015 | GEO

TERMINAL-SEQUENCE STUDIES OF HIGH-MOLECULAR-WEIGHT RIBONUCLEIC. THE REACTION OF PERIODATE-OXIDIZED RIBONUCLEOSIDES , 5'-RIBONUCLEOTIDES AND RIBONUCLEIC ACID WITH ISONIAZID.

Project description:1. The reaction products of isoniazid with periodate-oxidized ribonucleosides and 5'-ribonucleotides have been characterized as the monohydrazones. 2. The stability, chromatographic and electrophoretic properties of the hydrazones are described. 3. (3)H-labelled isoniazid was shown to react with the 5'-linked terminal adenosine and cytidine groups of periodate-oxidized Escherichia coli transfer RNA. One mole of isoniazid reacts with 27x10(3)g. of the transfer RNA. 4. One mole of (3)H-labelled isoniazid reacts with approx. 10(6)g. of rabbit-reticulocyte ribosomal RNA. After fractionation of the RNA into its two components and treating the fractionated material with pancreatic ribonuclease and ribonuclease T(1) evidence is presented for the existence of two 5'-linked terminal sequences in the 30s fraction and only one sequence in the 17s fraction. 5. The application of this method to determining terminal sequences of high-molecular-weight RNA is discussed.

| S-EPMC1214355 | biostudies-other

The effect of thioacetamide on the maturation of high-molecular-weight ribonucleic acid in tumour cells.

Project description:1. Although thioacetamide treatment of Krebs II ascites-tumour cells did not markedly affect the rate of RNA synthesis in vivo, it caused the formation of an unusual single-stranded RNA component sedimenting at approx. 26s. 2. The maturation process leading to the formation of methylated RNA was examined by following the kinetics of incorporation into RNA of radioactivity from [G-(3)H]uridine and l-[Me-(14)C]methionine. In treated and untreated tumour cells extensive methylation was observed, not only of the ribosomal RNA species, but also of their precursors, especially the precursor species sedimenting at 35s. 3. Evidence is also presented to suggest that methylation of low-molecular-weight RNA species occurs both in the nucleus and in the cytoplasm of these tumour cells. 4. Thioacetamide did not appear to have an effect on RNA methylation in vivo, and in thioacetamide-treated cells the 26s RNA accumulated within the nucleus, where it was methylated. 5. It is postulated that the 26s RNA is most likely to arise as a result of a fault in the scission process that gives rise to the ribosomal RNA components from their high-molecular-weight precursors.

| S-EPMC1270560 | biostudies-other

Terminal-sequence studies of high-molecular-weight ribonucleic acid. The 3'-termini of rabbit reticulocyte ribosomal RNA.

Project description:Sequences of the polynucleotide chains of RNA found in the large and small ribosomal subunits of rabbit reticulocytes have been determined from the 3'-end by use of periodate oxidation and condensation with [(3)H]isoniazid and by stepwise degradation. By these methods the hexanucleotide sequences have been found as -pGpUpUpUpGpU for the 28S RNA and -pGpUpCpGpCpU for the 6S RNA of the large ribosomal subunit and the octanucleotide sequence -pGpApUpCpApUpUpA for the 18S rRNA of the small ribosomal subunit. These sequences are present in at least 70% of all the RNA molecules and are discussed in relation to the specific cleavage of rRNA from its precursors and the role of multiple cistrons for rRNA in the DNA of higher organisms. The feasibility of using the method for longer sequence determinations is discussed.

| S-EPMC1179605 | biostudies-other

High-molecular-weight nuclear polyadenylate-containing ribonucleic acid isolated from the lactating guniea-pig mammary gland contains milk-protein messenger ribonucleic acid sequences.

Project description:1. Steady-state poly(A)-containing nuclear RNA was isolated from the lactating guinea-pig mammary gland and analysed by sucrose-gradient centrifugation under denaturing conditions. 2. Nucleic acid-hybridization studies demonstrated the presence of small amounts of high-molecular-weight RNA species containing milk-protein mRNA sequences sedimenting at 25S. These were not found in the post-nuclear supernatant, where milk-protein sequences sedimented only between 12S and 15S; these were also the predominant species in the nuclear fraction. 3. The results are consistent with the transcription of milk-protein genes as high-molecular-weight precursor RNA species, 3-4 times as large as the active mRNA species isolated from the post-nuclear fraction.

| S-EPMC1161182 | biostudies-other

What Is the Molecular Weight of "High" Molecular Weight Dissolved Organic Matter?

Project description:The use of ultrafiltration to isolate high molecular weight dissolved organic matter (HMWDOM) from seawater is a fundamental tool in the environmental organic chemist's toolbox. Yet, important characteristics of HMWDOM relevant to its origin and cycling, such as its molecular weight distribution, remain poorly defined. We used diffusion-ordered NMR spectroscopy coupled with mixed-mode chromatography to separate and characterize two major components of marine HMWDOM: acylpolysaccharides (APS) and high molecular weight humic substances (HS). The molecular weights (MWs) of APS and HS both fell within distinct, narrow envelopes; 2.0-16 kDa for APS and 0.9-6.5 kDa for HS. In water samples from the North Pacific Ocean the average MW of both components decreased with depth through the mesopelagic. However, the minimum MW of APS was >2 kDa, well above the molecular weight cutoff of the ultrafilter, suggesting APS removal processes below 2 kDa are highly efficient. The MW distribution of APS shows only small variations with depth, while the MW distribution of HS narrowed due to removal of HMW components. Despite the narrowing of the MW distribution, the concentration of HS did not decrease with depth between 15 and 915 m. This suggests that HMW HS produced in surface waters was either degraded into lower MW compounds without significant remineralization, or that HMW HS was remineralized but replaced by an additional source of HS in the mesopelagic ocean. Based on these results, we propose potential pathways for the production and removal of these major components of HMWDOM.

| S-EPMC11339928 | 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