Showing papers on "RNA published in 1979"
TL;DR: In this article, the rat pancreas RNA was used as a source for the purification of alpha-amylase messenger ribonucleic acid (RBA) using 2-mercaptoethanol.
Abstract: Intact ribonucleic acid (RNA) has been prepared from tissues rich in ribonuclease such as the rat pancreas by efficient homogenization in a 4 M solution of the potent protein denaturant guanidinium thiocyanate plus 0.1 M 2-mercaptoethanol to break protein disulfide bonds. The RNA was isolated free of protein by ethanol precipitation or by sedimentation through cesium chloride. Rat pancreas RNA obtained by these means has been used as a source for the purification of alpha-amylase messenger ribonucleic acid.
19,805 citations
TL;DR: Comparison of Hae III and Hpa II digestion of cereal rDNAs and the cloned repeats suggests that most methylated cytosines in natural rDNA are in -CpG-.
Abstract: Wheat and barley DNA enriched for ribosomal RNA genes was isolated from actinomycin D-CsCl gradients and used to clone the ribosomal repeating units in the plasmid pAC184. All five chimeric plasmids isolated which contained wheat rDNA and eleven of the thirteen which had barley rDNA were stable and included full length ribosomal repeating units. Physical maps of all length variants cloned have been constructed using the restriction endonucleases Eco Rl, Bam Hl, Bgl II, Hind III and Sal I. Length variation in the repeat units was attributed to differences in the spacer regions. Comparison of Hae III and Hpa II digestion of cereal rDNAs and the cloned repeats suggests that most methylated cytosines in natural rDNA are in -CpG-. Incomplete methylation occurs at specific Bam Hl sites in barley DNA. Detectable quantities of ribosomal spacer sequences are not present at any genomic locations other than those of the ribosomal RNA gene repeats.
1,413 citations
TL;DR: It is argued that each of the six snRNAs exists in a separate small nuclear ribonucleoprotein (snRNP) complex with a total molecular weight of about 175,000.
Abstract: Patients with systemic lupus erythematosus often possess antibodies against two nuclear antigens called Sm and RNP (ribonucleoprotein). We have established the molecular identity of these antigens by analyzing immune precipitates of nuclear extracts from mouse Ehrlich ascites cells labeled with 32P and 35S. Anti-Sm serum selectively precipitates six small nuclear RNA molecules (snRNAs); anti-RNP serum reacts with only two of these; and a third serum, characterized as mostly anti-RNP, precipitates a subset of three snRNA bands. Three of the six RNAs are identified by fingerprint analysis as the previously characterized and highly abundant nucleoplasmic snRNA species U1a (171 nucleotides), U1b, and U2 (196 nucleotides). The other three RNAs (U4, U5, and U6) likewise are uridine rich and contain modified nucleotides, but they are smaller, with lengths of about 145, 120, and 95 residues, respectively. Each of the six snRNAs is complexed with and apparently antigenic by virtue of association with specific proteins. All three sera precipitate an identical complement of seven different polypeptides ranging in molecular weight from 12,000 to 35,000; these proteins are abundant in nuclear extracts, but are neither histones nor the major polypeptides comprising the 30S heterogeneous nuclear RNP particles of mammalian nuclei. Our data argue that each of the six snRNAs exists in a separate small nuclear ribonucleoprotein (snRNP) complex with a total molecular weight of about 175,000. We find that human antisera also precipitate snRNAs from a wide range of vertebrate species and from arthropods. We discuss the antigenic snRNPs in relation to the published literature on snRNAs and nuclear RNPs and consider possible functions of snRNPs in nuclear processes.
1,002 citations
TL;DR: Relative rates of ovalbumin and conalbumin mRNA transcription were measured in isolated oviduct nuclei by allowing endogenous RNA polymerases to synthesize [32P]RNA that was then hybridized to immobilized recombinant DNA containing the respective gene sequences.
842 citations
TL;DR: Four different base-specific chemical reactions generate a means of directly sequencing RNA terminally labeled with 32P, which yields clean cleavage patterns for each purine and pyrimidine and allows a determination of the entire RNA sequence out to 100-200 bases from the labeled terminus.
Abstract: Four different base-specific chemical reactions generate a means of directly sequencing RNA terminally labeled with 32P. After a partial, specific modification of each kind of RNA base, an amine-catalyzed strand scission generates labeled fragments whose lengths determine the position of each nucleotide in the sequence. Dimethyl sulfate modifies guanosine. Diethyl pyrocarbonate attacks primarily adenosine. Hydrazine attacks uridine and cytidine, but salt suppresses the reaction with uridine. In all cases, aniline induces a subsequent strand scission. The electrophoretic fractionation of the labeled fragments on a polyacrylamide gel, followed by autoradiography, determines the RNA sequence. RNA labeled at the 3' end yields clean cleavage patterns for each purine and pyrimidine and allows a determination of the entire RNA sequence out to 100-200 bases from the labeled terminus.
744 citations
TL;DR: The observation of the circular form of RNA extracted from the cytoplasm of several eukaryotic cells is reported.
Abstract: LINEAR single-stranded RNA genomes extracted from several RNA viruses were found to exist in a circular conformation when examined in the electron microscope in partially denaturing conditions1–4. The circular conformation of viral RNA presumably arises from base pairing between RNA sequences at the two ends of the RNA molecules. The biological significance of the circular structure of single-stranded RNA is still unknown. Here we report the observation of the circular form of RNA extracted from the cytoplasm of several eukaryotic cells.
726 citations
TL;DR: It is demonstrated that the expression of many early adenovirus mRNAs is dependent upon the activity of a pre-early viral product, which is defective in adanovirus 5 host range (Ad hr) group I mutants.
642 citations
TL;DR: Results are not consistent with negative control of late transcription through the action of a repressor and, taken together with other data, suggest that T antigen has an active role in late RNA synthesis.
Abstract: We have examined the discrete species of simian virus 40 (SV40) RNA present very early in infection of monkey cells with wild-type virus, with mutant tsA58 virus, and with the corresponding DNAs to distinguish between two classes of models for control of late transcription: (i) positive control mediated by large-T antigen and (ii) negative control mediated by a repressor protein associated with viral DNA in the virion. Total cytoplasmic or nuclear polyadenylated RNAs from infected cells were denatured with glyoxal, separated by electrophoresis on agarose gels, and transferred to diazobenzyloxymethyl paper. The positions of specific early and late RNA species were determined with region-specific SV40 DNA probes. The technique can detect individual RNAs present at the level of less than one copy per cell. After 9.5 h at 37 degrees C, appreciable amounts of two early RNAs (2.6 kilobases [kb] and 2.9 kb) were present in the cytoplasm of cells infected with wild-type virus or DNA, along with much smaller amounts of two late RNAs, 1.6 kb (16S) and 2.5 kb (19S). The amounts of the late RNAs were reduced, but they were still synthesized in the presence of cytosine arabinoside, an inhibitor of DNA synthesis. In comparable infections with tsA58 virus or DNA at nonpermissive temperature (41 degrees C), substantial amounts of the two early RNAs were again present, but the two late RNAs could not be detected. However, small amounts of the late RNAs were found when infections with tsA58 virus or DNA were prolonged to 30 h at 41 degrees C. These results are not consistent with negative control of late transcription through the action of a repressor and, taken together with other data, suggest that T antigen has an active role in late RNA synthesis. Specific early and late viral RNAs were also detected in the nuclear poly(A)(+) fractions and were similar in size to the RNA species found in the cytoplasmic polyadenylated fractions. The late nuclear RNAs (1.8 and 2.9 kb) were significantly larger than the late cytoplasmic species, possibly because they are precursors. The 2.6- and 2.9-kb early RNAs found in the cytoplasm are probably the messengers for large-T and small-t antigens, respectively.
517 citations
TL;DR: It is surprising that both complements of most repeat sequences are present in nuclear RNA, which leads to model for regulation of gene expression in which the formation of repetitive RNA-RNA duplexes controls the production of messenger RNA.
Abstract: Large contrasts are observed between the messenger RNA populations of different tissues and of embryos at different stages of development. Nevertheless, coding sequences for genes not expressed in a cell appear to be present in its nuclear RNA. Though many nuclear RNA transcripts of single copy DNA sequences are held in common between tissues, an additional set, probably consisting of non-message sequences, is not shared. Nuclear RNA also contains transcripts of repetitive DNA sequences. Certain repeat families are represented at high levels in the nuclear RNA of particular tissues and much lower levels in others. It is surprising that both complements of most repeat sequences are present in nuclear RNA. These observations lead to model for regulation of gene expression in which the formation of repetitive RNA-RNA duplexes controls the production of messenger RNA.
495 citations
TL;DR: From the large, complex arrays of composite RNA structures, numerous insights into the RNA splicing mechanisms were inferred.
488 citations
TL;DR: Poly A containing RNA isolated from embryonic chick calvaria was transferred from 6% formaldehyde 0.75% agarose gels to diazobenzyloxymethyl paper and the paper was hybridized to either nick translated pro alpha 1 collagen cDNA clones, pCg1 or pCG54, or to the nick translation pro alpha 2 collagen c DNA clone,pCg45.
Abstract: Poly A containing RNA isolated from embryonic chick calvaria was transferred from 6% formaldehyde 075% agarose gels to diazobenzyloxymethyl paper and the paper then hybridized to either nick translated pro alpha 1 collagen cDNA clones, pCg1 or pCg54, or to the nick translated pro alpha 2 collagen cDNA clone, pCg45 From the mobilities of the bands hybridizing most strongly to each, pro alpha 2 collagen mRNA was shown to be slightly larger than pro alpha 1 mRNA; they are 5100 and 4900 nucleotides long respectively pCg54 also hybridized weakly to two bands of lower mobility, corresponding to RNAs 64 and 56 kb long Neither pCg54 nor pCg45 hybridized to type II procollagen mRNA in poly A containing RNA isolated from embryonic chick sterna
TL;DR: It is reported that this drug inhibits growth and cytopathology of several unrelated DNA and RNA viruses, while not affecting cell activity and ability to replicate, and inactivates herpes simplex virus particles irreversibly.
Abstract: Screening investigations in antiviral action of plant extracts have revealed that a component of Glycyrrhiza glabra roots, found to be glycyrrhizie acid, is active against viruses. We report here that this drug inhibits growth and cytopathology of several unrelated DNA and RNA viruses, while not affecting cell activity and ability to replicate. In addition, glycyrrhizic acid inactivates herpes simplex virus particles irreversibly.
TL;DR: The structure of S6 and conditions Altering the Phosphorylation of S 6 are modified and the number of Ribosomal Proteins is increased, leading to a higher concentration of ribosomal RNA.
Abstract: PERSPECTIVES AND SUMMARY . GENERAL CHARACTERISTICS OF EUKARYOTIC RIBOSOMES .. ISOLATION AND CHARACTERIZATION OF EUKARYOTIC RIBOSOMAL PROTEINS .. Purification . Characterization . The Number of Ribosomal Proteins .. Stoichiometry . Sequence Analyses . THE ASSOCIATION OF RIBOSOMAL PROTEINS AND RIBOSOMAL RNA PHOSPHORYLATION OF EUKARYOTIC RIBOSOMAL PROTEINS .. Structure of S6 . Conservation of S6 . Conditions Altering the Phosphorylation of S6 . Acidic Ribosomal Phosphoproteins .. Relation of Rat Liver PI and P2 to E. Coli L7/L12 .. Artemia Salina Acidic Ribosomal Phosphoproteins ..
TL;DR: The fine structure map of the yeast URA 3 gene was established by meiotic recombination, and amber nonsense mutations were located at different points on the map, and nonsense mutations reduce the messenger level without lowering its instantaneous rate of synthesis.
Abstract: The fine structure map of the yeast URA 3 gene was established by meiotic recombination, and amber nonsense mutations were located at different points on the map. The effect of the length of the labeling time on the specific radioactivity of ura 3 messenger RNA and on its repartition between poly(A)-RNA and RNA not containing poly(A) has been followed in nonsense mutants. Nonsense mutations reduce the messenger level without lowering its instantaneous rate of synthesis. The strength of the reduction depends on the position of the nonsense codon within the locus and concerns essentially the accumulation of polyadenylylated ura 3 mRNA.
TL;DR: A number of genes in higher organisms and in their viruses appear to be split, which means they have "nonsense" stretches of DNA interspersed within the sense DNA.
Abstract: A number of genes in higher organisms and in their viruses appear to be split. That is, they have "nonsense" stretches of DNA interspersed within the sense DNA. The cell produces a full RNA transcript of this DNA, nonsense and all, and then appears to splice out the nonsense sequences before sending the RNA to the cytoplasm. In this article what is known about these intervening sequences and about the processing of the RNA is outlined. Also discussed is their possible use and how they might have arisen in evolution.
TL;DR: A simple procedure for isolating specific mRNAs and for mapping them to the regions of the DNA from which they originate is described and eluted and translated in a cell-free system in order to identify their encoded polypeptides.
Abstract: We describe a simple procedure for isolating specific mRNAs and for mapping them to the regions of the DNA from which they originate. The method involves hybridization of total cytoplasmic RNA to restriction fragments of DNA that have been fractionated in agarose gels and immobilized on nitrocellulose filters. The hybridization-selected RNAs are eluted and translated in a cell-free system in order to identify their encoded polypeptides. Optimal hybridization and filter washing conditions are given for selection of mRNAs from adenovirus 2-infected cells and transformed cells.
TL;DR: Recent work has focused on the enzymatic differences between extracts of interferon-treated and control cells reported by several investigators, and studies examining the stability of 2,5A in cell extracts are described, which may help to understand how the endoribonuclease functions in virus-infected interferons-treated cells.
TL;DR: The hybridization of a DNA oligonucleotide a specific tetramer or longer will direct a cleavage by RNase H to a specific site in RNA, which can then be labeled at their 5' or 3' ends, purified, and sequenced directly.
Abstract: The hybridization of a DNA oligonucleotide a specific tetramer or longer) will direct a cleavage by RNase H (EC 3.1.4.34) to a specific site in RNA. The resulting fragments can then be labeled at their 5' or 3' ends, purified, and sequenced directly. This procedure is demonstrated with two RNA molecules of known sequence: 5.8S rRNA from yeast (158 nucleotides) and satellite tobacco necrosis virus (STNV) RNA (1240 nucleotides).
TL;DR: Results indicate that a relatively long stretch of base pairs, uninterrupted by either a mismatch or a discontinuity in one of the complementary strands, is required for the activation of the two enzymes studied.
TL;DR: By comparing the nucleotide alignments, this work proposes a phylogenic tree of the 54 5S RNA species and suggests a possible mechanism for the conversion of the prokaryotic 116-N type to the 120-Ntype 5S RNAs (or vice versa), which may be further classified into two types.
Abstract: Secondary structure models of 54 5S RNA species are constructed based on the comparative analyses of their primary structure. All 5S RNAs examined have essentially the same secondary structure. However, there are revealing characteristic differences between eukaryotic and prokaryotic types. The prokaryotic 5S RNAs may be further classified into two types, one having 120 nucleotides (120-N type) and another having 116 (116-N type). A possible mechanism for the conversion of the prokaryotic 116-N type to the 120-N type 5S RNAs (or vice versa) is discussed on the basis of their nucleotide alignments. Finally, by comparing the nucleotide alignments, we propose a phylogenic tree of the 54 5S RNA species.
TL;DR: All three properties (58K protein, phosphoprotein, in vitro phosphorylation) are closely correlated with transformation in cells transformed by temperature-sensitive viruses.
TL;DR: Denaturation--renaturation studies indicate that sigma is capable of an unusually rapid and complete recovery of activity after being subjected to denaturing conditions.
Abstract: An improved purification procedure is described for the sigma subunit of escherichia coli DNA-dependent RNA polymerase [ribonucleoside triphosphate:RNA nucleotidyl-transferase, EC 2.7.7.6]. The method involves chromatography of purified RNA polymerase on single-stranded DNA-agarose, Bio-Rex 70, and finally Ultragel AcA44. The sigma factor obtained is electrophoretically pure with a yield of about 40%. A number of the chemical--physical properties of sigma are presented. A molecular weight of 82,000 was determined by phosphate buffered sodium dodecyl sulfate--polyacrylamide gel electrophoresis. Ultraviolet absorption spectra were used to determine an E280nm 1% of 8.4. The amino acid composition and 12-residue N-terminal sequence (Met-Glx-Glx-Asx-Pro-Glx-(Ser or Cys)-Glx-Leu-Lys-Leu-Leu) of sigma have been determined. The isoelectric focusing properties of sigma are presented. Denaturation--renaturation studies indicate that sigma is capable of an unusually rapid and complete recovery of activity after being subjected to denaturing conditions. A stable, 40,000-dalton fragment is generated from sigma by mild trypsin treatment.
TL;DR: Cloned DNA sequences complementary to unselected mRNAs from Chinese hamster ovary cells are constructed and used in RNA:DNA hybridization experiments, suggesting the synthesis of many hnRNA molecules that are qualitatively different from those which eventually contribute mRNA to the cytoplasm.
TL;DR: The inhibition of reverse transcriptase activity by suramin was competitive with the template-primer, (A) n · oligo(dT), suggesting that the drug may interact with the Template Primer binding site of the enzyme.
TL;DR: Multiple nitrocellulose DNA filter replicas of plaques of in vitro generated recombinants of phage lambda and Saccharomyces cerevisiae have been screened by hybridization with 32P-labeled cDNA probes to allow the use of specific differences in total RNA populations as probes for gene isolation.
TL;DR: The data suggest that evolution of oncogenic retroviruses has frequently involved a mechanism whereby incorporation and perhaps modification of different host genes provides each virus with the ability to induce its characteristic tumors.
Abstract: The avian carcinoma virus MC29 (MC29V) contains a sequence of approximately 1,500 nucleotides which may represent a gene responsible for tumorigenesis by MC29V. We present evidence that MC29V has acquired this nucleotide sequence from the DNA of its host. The host sequence which has been incorporated by MC29V is transcribed into RNA in uninfected chicken cells and thus probably encodes a cellular gene. We have prepared radioactive DNA complementary to the putative MC29V transforming gene (cDNA(mc) (29)) and have found that sequences homologous to cDNA(mc) (29) are present in the genomes of several uninfected vertebrate species. The DNA of chicken, the natural host for MC29V, contains at least 90% of the sequences represented by cDNA(mc) (29). DNAs from other animals show significant but decreasing amounts of complementarity to cDNA(mc) (29) in accordance with their evolutionary divergence from chickens; the thermal stabilities of duplexes formed between cDNA(mc) (29) and avian DNAs also reflect phylogenetic divergence. Sequences complementary to cDNA(mc) (29) are transcribed into approximately 10 copies per cell of polyadenylated RNA in uninfected chicken fibroblasts. Thus, the vertebrate homolog of cDNA(mc) (29) may be a gene which has been conserved throughout vertebrate evolution and which served as a progenitor for the putative transforming gene of MC29V. Recent experiments suggest that the putative transforming gene of avian erythroblastosis virus, like that of MC29V, may have arisen by incorporation of a host gene (Stehelin et al., personal communication). These findings for avian erythroblastosis virus and MC29V closely parallel previous results, suggesting a host origin for src (D. H. Spector, B. Baker, H. E. Varmus, and J. M. Bishop, Cell 13:381-386, 1978; D. H. Spector, K. Smith, T. Padgett, P. McCombe, D. Roulland-Dussoix, C. Moscovici, H. E. Varmus, and J. M. Bishop, Cell 13:371-379, 1978; D. H. Spector, H. E. Varmus, and J. M. Bishop, Proc. Natl. Acad. Sci. U.S.A. 75:4102-4106, 1978; D. Stehelin, H. E. Varmus, J. M. Bishop, and P. K. Vogt, Nature [London] 260:170-173, 1976), the gene responsible for tumorigenesis by avian sarcoma virus. Avian sarcoma virus, avian erythroblastosis virus, and MC29V, however, induce distinctly different spectra of tumors within their host. The putative transforming genes of these viruses share no detectable homology, although sequences homologous to all three types of putative transforming genes occur and are highly conserved in the genomes of several vertebrate species. These data suggest that evolution of oncogenic retroviruses has frequently involved a mechanism whereby incorporation and perhaps modification of different host genes provides each virus with the ability to induce its characteristic tumors.
TL;DR: A synthetic fowl plague virus (FPV) haemagglutinin gene has been cloned in bacteria and the complete sequence of the RNA gene deduced.
Abstract: A synthetic fowl plague virus (FPV) haemagglutinin gene has been cloned in bacteria and the complete sequence of the RNA gene deduced. It is 1,742 nucleotides long and the mRNA codes for 563 amino acids in an uninterrupted sequence. The nature of some of the important domains in the haemagglutinin has been established, and their structure is discussed in relation to their function. Extensive amino acid sequence homologies exist between FPV and human influenza haemagglutinins.
TL;DR: The RNA of infectious bursal disease virus was reexamined in a detailed analysis and it could be established that its genome consists of two segments of double-stranded RNA.
Abstract: The RNA of infectious bursal disease virus was reexamined in a detailed analysis. It could be established that its genome consists of two segments of double-stranded RNA. The RNA is RNase resistant and has a sedimentation coefficient of 14S and a buoyant density of 1.62 g/ml. The purine/pyrimidine ratio is nearly 1; the guanine plus cytosine content is 55.3%; the Tm is 95.5 degrees C. The molecular weights of the two double-stranded segments were determined to be 2.2 x 10(6) and 2.5 x 10(6).