Some features of nucleo-cytoplasmic RNA transport from isolated nuclei

1981 ◽  
Vol 7 (1-3) ◽  
pp. 25-30 ◽  
Author(s):  
A. V. Peskin ◽  
Y. M. Koen ◽  
I. B. Zbarsky
Keyword(s):  
Rna Transport ◽  
Isolated Nuclei ◽  
Cytoplasmic Rna

scholarly journals Importance of mammalian nuclear-envelope nucleoside triphosphatase in nucleo-cytoplasmic transport of ribonucleoproteins

1979 ◽  
Vol 182 (3) ◽  
pp. 811-819 ◽  
Author(s):  
P S Agutter ◽  
B McCaldin ◽  
H J McArdle
Keyword(s):  
Ionic Strength ◽  
Substrate Specificity ◽  
Nuclear Envelope ◽  
Nucleoside Triphosphate ◽  
Rna Transport ◽  
Isolated Nuclei ◽  
Cytoplasmic Rna ◽  
Cytoplasmic Transport ◽  
Nucleoside Triphosphatase

The nucleoside triphosphate-stimulated efflux of RNA from isolated nuclei was studied under a range of conditions, and the effects of these conditions on the process were compared with the properties of the nucleoside triphosphatase located in the pore complex. A marked similarity between the rate of efflux and the rate of nucleoside triphosphate hydrolysis was apparent, in terms of substrate specificity, sensitivity to treatment with insolubilized trypsin, kinetics and the effects of increased ionic strength and of many inhibitors. These results are taken, in view of earlier evidence, to suggest that the activity of the nucleoside triphosphatase is a prerequisite for nucleo-cytoplasmic RNA transport in vivo. There are some indications that the nuclear-envelope lipid is also involved in regulating the efflux process.

The ribosenucleic acid content of isolated cell nuclei

1952 ◽  
Vol 214 (1118) ◽  
pp. 427-427
Keyword(s):  
Nucleic Acids ◽  
Acid Content ◽  
Isolation Procedure ◽  
Cell Nuclei ◽  
Isolated Nuclei ◽  
Rna Content ◽  
Cytoplasmic Rna ◽  
Different Types ◽  
Isolated Cell

A method is described for the estimation, by furfural formation, of small amounts of ribosenucleic acid (RNA) in the presence of large amounts of deoxyribosenucleic acid. Evidence is produced to show that the Schmidt and Thannhauser method does not give a satisfactory separation of the two types of nucleic acids. The method has been applied to the estimation of the RNA content of nuclei isolated from a number of different types of cell, and the values reported. It is concluded that the nuclei as isolated contain small amounts of RNA, but the possibility of adsorption of cytoplasmic RNA by the nuclei during the isolation procedure cannot be excluded. No correlation was found between the RNA content of the isolated nuclei and the prominence of their nucleolar systems.

scholarly journals PTB/hnRNP I Is Required for RNP Remodeling during RNA Localization in Xenopus Oocytes

2007 ◽  
Vol 28 (2) ◽  
pp. 678-686 ◽  
Author(s):  
Raymond A. Lewis ◽  
James A. Gagnon ◽  
Kimberly L. Mowry
Keyword(s):  
Protein Interactions ◽  
Xenopus Oocytes ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Rna Localization ◽  
Rna Transport ◽  
Rna Sequences ◽  
Cytoplasmic Rna ◽  
Embryonic Polarity ◽  
Specific Mrnas

ABSTRACT Transport of specific mRNAs to defined regions within the cell cytoplasm is a fundamental mechanism for regulating cell and developmental polarity. In the Xenopus oocyte, Vg1 RNA is transported to the vegetal cytoplasm, where localized expression of the encoded protein is critical for embryonic polarity. The Vg1 localization pathway is directed by interactions between key motifs within Vg1 RNA and protein factors recognizing those RNA sequences. We have investigated how RNA-protein interactions could be modulated to trigger distinct steps in the localization pathway and found that the Vg1 RNP is remodeled during cytoplasmic RNA transport. Our results implicate two RNA-binding proteins with key roles in Vg1 RNA localization, PTB/hnRNP I and Vg1RBP/vera, in this process. We show that PTB/hnRNP I is required for remodeling of the interaction between Vg1 RNA and Vg1RBP/vera. Critically, mutations that block this remodeling event also eliminate vegetal localization of the RNA, suggesting that RNP remodeling is required for localization.

scholarly journals Nature of the facilitated messenger ribonucleic acid transport from isolated nuclei

1976 ◽  
Vol 154 (2) ◽  
pp. 379-385 ◽  
Author(s):  
A Yannarell ◽  
D E. Schumm ◽  
T E Webb
Keyword(s):  
Concentration Dependence ◽  
Ribonucleic Acid ◽  
High Specificity ◽  
Effective Concentration ◽  
Regulatory Proteins ◽  
Rna Transport ◽  
Acid Transport ◽  
Isolated Nuclei ◽  
Messenger Ribonucleic Acid ◽  
Quantitative Changes

Cytoplasmic macromolecules were previously identified which regulate both qualitatively and quantitatively the release of messenger-like RNA from isolated nuclei. These macromolecules are now shown to be denatured at 45-50 degrees C and their synthesis is sensitive to pactamycin or cycloheximide. The putative regulatory proteins are essentially quantitatively precipitated with high specificity from the cytosol by streptomycin at a concentration 10-fold higher than that used to precipitate RNA. The nuclear concentration-dependence of RNA transport from successive samples of nuclei strongly suggests that the regulatory factors are recycled. Quantitative changes in the sequences transported at various dilutions of the cytosol suggest that not all the different classes of the putative regulatory macromolecules are present in an effective concentration at any one dilution.

scholarly journals Role of cytosol in the stimulation of RNA transport in vitro during cardiac hypertrophy in rats

1990 ◽  
Vol 267 (1) ◽  
pp. 133-140 ◽  
Author(s):  
A Subramaniam ◽  
M Thirunavukkarasu ◽  
C Rajamanickam
Keyword(s):  
Myosin Heavy Chain ◽  
Heavy Chain ◽  
Deae Cellulose ◽  
Gene Probe ◽  
Rna Transport ◽  
Transport Activity ◽  
Isolated Nuclei ◽  
Stimulation Of

The 100,000 g supernatant isolated from hypertrophic hearts on fractionation by (NH4)2SO4 and DEAE-cellulose chromatography showed an enhanced RNA-transport activity when incubated with isolated nuclei from sham-operated hearts in vitro. Proteins of Mr 73,000, 68,000, 43,000 and 32,000 are enriched in the DEAE-cellulose fractions exhibiting maximal transport activity, and they are phosphorylatable. Pretreatment of the cytosol with antibodies to the Mr-68,000 and -32,000 proteins decreases the transport activity of the cytosol from 14% to 4.25%. Proteins of Mr 73,000, 68,000, 43,000 and 32,000 are translocated from the cytosol to the nuclear envelope under conditions of RNA transport in vitro. Our results here suggest that at least two of these proteins, those of Mr 68,000 and 32,000, play an indispensible role in the nucleocytoplasmic RNA transport in vitro. By making use of a specific myosin heavy-chain B-gene probe and hybridization, we have also shown the effect of cytosol on the transport of myosin heavy-chain mRNA from nucleus to cytosol.

scholarly journals Cis-acting determinants of asymmetric, cytoplasmic RNA transport

RNA ◽  
2007 ◽  
Vol 13 (5) ◽  
pp. 625-642 ◽  
Author(s):  
A. Jambhekar ◽  
J. L. DeRisi
Keyword(s):  
Rna Transport ◽  
Cis Acting ◽  
Cytoplasmic Rna

scholarly journals Evidence for Two Metabolically Distinct Types of Ribonucleic Acid in Chromatin and Nucleoli

1958 ◽  
Vol 4 (1) ◽  
pp. 5-11 ◽  
Author(s):  
Rachel McMaster-Kaye ◽  
J. Herbert Taylor
Keyword(s):  
Maximum Activity ◽  
The Other ◽  
Precise Localization ◽  
Isolated Nuclei ◽  
Metabolic Characteristics ◽  
Nucleolar Activity ◽  
Cytoplasmic Rna ◽  
Nuclear Rna ◽  
Time Courses ◽  
Nucleolar Rna

Patterns of radioisotope incorporation are useful characteristics in describing cellular RNA fractions, and have indicated a distinctive "nuclear" RNA. In order to characterize the RNA fractions of the two nuclear components, nucleoli and chromatin, and to determine thereby the precise localization of the RNA typical of isolated nuclei, time-courses of P32 incorporation into nucleolar, chromosomal, and cytoplasmic RNA of Drosophila salivary glands have been determined from autoradiograms. Two experiments are reported which cover 12 and 18 hour periods, including an initial 2 hour feeding on P32. Concentrations of RNA-P32 (identified by ribonuclease digestion) were determined by grain counts. After 1 hour only the nucleolar RNA is labelled. Activity is detectible in chromosomal and cytoplasmic RNA after the 2nd hour. The nucleolar fraction reaches its maximum activity shortly after transfer of the larvae to non-radioactive food, the other fractions several hours later. Maximum activities persist in the chromosomal and cytoplasmic fractions; nucleolar activity decreases after the 9th hour. The observed differences in times at which incorporation begins and maximum activities are reached, and in maintenance of maximum activities indicate that chromosomal and nucleolar RNA are distinct fractions. The metabolic characteristics which have been ascribed to "nuclear" RNA apply only to the nucleolar fraction.

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