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RNA Biology 2015The Spot 42 RNA is a 109 nucleotide long (in Escherichia coli) noncoding small regulatory RNA (sRNA) encoded by the spf (spot fourty-two) gene. spf is found in... (Review)
Review
The Spot 42 RNA is a 109 nucleotide long (in Escherichia coli) noncoding small regulatory RNA (sRNA) encoded by the spf (spot fourty-two) gene. spf is found in gamma-proteobacteria and the majority of experimental work on Spot 42 RNA has been performed using E. coli, and recently Aliivibrio salmonicida. In the cell Spot 42 RNA plays essential roles as a regulator in carbohydrate metabolism and uptake, and its expression is activated by glucose, and inhibited by the cAMP-CRP complex. Here we summarize the current knowledge on Spot 42, and present the natural distribution of spf, show family-specific secondary structural features of Spot 42, and link highly conserved structural regions to mRNA target binding.
Topics: Carbohydrate Metabolism; Escherichia coli; Gene Expression Regulation, Bacterial; Nucleic Acid Conformation; RNA, Bacterial; RNA, Messenger; RNA, Small Untranslated; Regulatory Sequences, Ribonucleic Acid
PubMed: 26327359
DOI: 10.1080/15476286.2015.1086867 -
Pathogens and Disease Jun 2018Since the turn of the millenium, RNA-based control of gene expression has added an extra dimension to the central dogma of molecular biology. Still, the roles of... (Review)
Review
Since the turn of the millenium, RNA-based control of gene expression has added an extra dimension to the central dogma of molecular biology. Still, the roles of Mycobacterium tuberculosis regulatory RNAs and the proteins that facilitate their functions remain elusive, although there can be no doubt that RNA biology plays a central role in the baterium's adaptation to its many host environments. In this review, we have presented examples from model organisms and from M. tuberculosis to showcase the abundance and versatility of regulatory RNA, in order to emphasise the importance of these 'fine-tuners' of gene expression.
Topics: Aconitate Hydratase; Bacterial Proteins; Gene Expression Regulation, Bacterial; Host-Pathogen Interactions; Humans; Mycobacterium tuberculosis; Nucleic Acid Conformation; RNA Stability; RNA, Bacterial; RNA, Small Cytoplasmic; RNA, Small Nuclear; RNA, Small Untranslated; Regulatory Sequences, Ribonucleic Acid; Riboswitch; Tuberculosis
PubMed: 29796669
DOI: 10.1093/femspd/fty035 -
The Journal of Biological Chemistry Sep 1962
Topics: Adenine Nucleotides; Adenosine; Adenosine Monophosphate; Adipose Tissue; Insulin; Nucleosides; Nucleotides; RNA
PubMed: 13886991
DOI: No ID Found -
Nature Sep 1951
Topics: Nucleic Acids; RNA
PubMed: 14875103
DOI: 10.1038/168406a0 -
Journal of Bacteriology Nov 1962Suit, Joan C. (The University of Texas M. D. Anderson Hospital and Tumor Institute, Houston). Ribonucleic acid in a "membrane" fraction of Escherichia coli and its...
Suit, Joan C. (The University of Texas M. D. Anderson Hospital and Tumor Institute, Houston). Ribonucleic acid in a "membrane" fraction of Escherichia coli and its relation to cell-wall synthesis. J. Bacteriol. 84:1061-1070. 1962.-A small amount of ribonucleic acid (RNA) was found in a "membrane" fraction prepared from osmotically sensitized Escherichia coli. It exhibited an elevated metabolic activity in that it attained the highest specific activity of any RNA in subcellular fractions of logarithmic-phase cells or spheroplasts prepared from logarithmic-phase cells which had been allowed to incorporate P(32) briefly. The metabolic activity of this RNA, in terms of P(32) incorporation, was found to be independent of cell-wall synthesis in the diaminopimelic acid (DAP)-less mutant, E. coli W 173-25, but was inhibited by penicillin in both this strain and in E. coli B. The latter effect is considered to be a result of other complex inhibitions of cellular metabolism by the antibiotic. The development of sensitivity to osmotic shock, capability of recovery, and synthesis of macromolecules in penicillin-treated and DAP-starved cultures, under these conditions, is described.
Topics: Cytoplasm; DNA; DNA, Bacterial; Diaminopimelic Acid; Escherichia coli; Penicillin G; Pimelic Acids; RNA; RNA, Bacterial; Spheroplasts
PubMed: 13979166
DOI: 10.1128/jb.84.5.1061-1070.1962 -
The Journal of Biophysical and... Dec 1961A study has been made of the content and composition of RNA in cytoplasm, nucleoplasm, and nucleoli from growing oocytes of the starfish Asterias rubens. The...
A study has been made of the content and composition of RNA in cytoplasm, nucleoplasm, and nucleoli from growing oocytes of the starfish Asterias rubens. The determinations were carried out, using ultramicrochemical methods, on units isolated by microdissection from fixed sections. Macrochemical and interferometric control experiments show that RNA can be quantitatively evaluated in this way. The results show that the growing oocyte represents a system in which the relations between the quantities of nucleolar, nucleoplasmic, and cytoplasmic RNA undergo great changes. These changes are continuous for nucleolar and cytoplasmic RNA so that their amounts may be predicted from the size of the cell. Nucleoplasmic RNA, on the other hand, shows great variations among different cells, independent of cell size. Purine-pyrimidine analyses show that each cell component contains an RNA which differs significantly from that of the other two. Cytoplasmic and nucleolar RNA are closely related, the only difference being a slightly higher guanine/uracil quotient for the nucleolar RNA. They are both of the usual tissue RNA type, i.e., they show a preponderance of guanine and cytosine over adenine and uracil. Nucleoplasmic RNA deviates grossly from the RNA of the other two components. Here the concentrations of adenine and uracil are higher than those of guanine and cytosine, respectively. This RNA consequently shows some resemblance to the general type of animal DNA although the purine/pyrimidine ratio is far from unity. Our data favor a nucleolar origin for the stable part of the ribosomal RNA and a nucleoplasmic one for the unstable part (the messenger RNA).
Topics: Adenine; Animals; Cell Nucleolus; Cell Nucleus; Cytoplasm; Cytosine; DNA; Guanine; Oocytes; Ovum; RNA; RNA, Messenger; RNA, Ribosomal; Starfish; Uracil
PubMed: 13889253
DOI: 10.1083/jcb.11.3.549 -
Correlations between ribonucleic acid and deoxyribonucleic acid metabolism during spore germination.Journal of Bacteriology Dec 1960
Topics: Animals; Bacillus; DNA; Insecta; RNA; Spores
PubMed: 13786172
DOI: 10.1128/jb.80.6.811-817.1960 -
The Journal of Experimental Medicine Nov 1960A relatively sensitive and adequately reproducible assay of infectious enteroviral RNA was obtained by exposing calf serum-grown HeLa cells to RNA suspended in 2 M...
A relatively sensitive and adequately reproducible assay of infectious enteroviral RNA was obtained by exposing calf serum-grown HeLa cells to RNA suspended in 2 M magnesium sulfate solution. Highly purified enteroviral preparations yielded RNA exhibiting more than 0.1 per cent of the infectivity of whole original virus and infectivity regressed linearly with dilution. Radioisotope experiments with P(32)-labeled RNA and spectrophotometric studies demonstrated that Gierer-Schramm phenol extraction permits almost quantitative recovery of high molecular weight RNA from poliovirus. Intact chromatography-purified type 2 poliovirus in the analytical ultracentrifuge showed a sharp boundary and a sedimentation coefficient of S(20, w) = 147 +/- 5S. Phenol-extracted poliovirus RNA exhibited a heterodisperse sedimentation pattern with a large proportion of homogeneous, rapidly sedimenting material having a coefficient of S(20, w) = 37 +/- 2S. Although the bulk of extracted poliovirus RNA as measured by radiophosphorus labeling was not taken up by cells, the infectious fraction of RNA was adsorbed rapidly by HeLa-cell or L strain mouse fibroblast monolayers, indicating a possible dissimilarity between the bulk of extracted virus RNA and a relatively small fraction responsible for infectivity. Enhancement of poliovirus RNA infectivity for HeLa cells by high ionic-strength magnesium sulfate solution appeared due partly to an effect of hypertonicity on cells, and partly to an effect of high-concentration divalent cation on RNA itself, but not to enhancement of adsorption. Poliovirus RNA adsorbed by HeLa cells apparently was rapidly received within the cells since it became quickly insusceptible to ribonuclease. Heterologous nucleic acids and degradation products to the level of oligoribonucleotides inhibited infectivity of poliovirus RNA for HeLa cells. This inhibitory activity appeared due to intermolecular complexing, since exposure of cells to heterologous RNA immediately before or after exposure to virus RNA failed to reduce infectivity. Ultraviolet absorption spectra demonstrated that the RNA within intact poliovirus is more hypochromic (and thus more extensively hydrogen-bonded) than is the same RNA isolated by phenol extraction, and suspended in 0.02 M phosphate buffer.
Topics: HeLa Cells; Humans; Poliovirus; RNA; RNA, Viral; Viruses
PubMed: 13715281
DOI: 10.1084/jem.112.5.821 -
RNA (New York, N.Y.) Oct 2010Four recent studies suggest that cleavages of transfer RNAs generate products with microRNA-like features, with some evidence of function. If their regulatory functions... (Review)
Review
Four recent studies suggest that cleavages of transfer RNAs generate products with microRNA-like features, with some evidence of function. If their regulatory functions were to be confirmed, these newly revealed RNAs would add to the expanding repertoire of small noncoding RNAs and would also provide new perspectives on the coevolution of transfer RNA and messenger RNA.
Topics: Animals; Evolution, Molecular; Humans; MicroRNAs; Models, Biological; RNA, Messenger; RNA, Transfer; RNA, Untranslated; Regulatory Sequences, Ribonucleic Acid
PubMed: 20719919
DOI: 10.1261/rna.2266510 -
Current Opinion in Microbiology Apr 2007Riboswitches are segments of the 5'-untranslated region of certain bacterial mRNAs that upon recognition of specific ligands modify the expression of a protein(s)... (Review)
Review
Riboswitches are segments of the 5'-untranslated region of certain bacterial mRNAs that upon recognition of specific ligands modify the expression of a protein(s) encoded in the message. These proteins are responsible for the biosynthesis or transport of ligands, which are typically organic molecules but could also be metal ions. Riboswitch-mediated control of gene expression might be thermodynamic or kinetic, depending on the rate of transcription elongation by RNA polymerase and the structures adopted by the riboswitch RNA. Certain 5'-untranslated regions harbor two riboswitches in tandem that bind to different ligands. Thus, RNA sensors can respond to metabolic changes by modifying gene expression in ways previously thought to be exclusive of proteins.
Topics: 5' Untranslated Regions; Bacteria; Gene Expression Regulation, Bacterial; Kinetics; Ligands; Magnesium; RNA, Bacterial; RNA, Messenger; Regulatory Sequences, Ribonucleic Acid; Thermodynamics
PubMed: 17383225
DOI: 10.1016/j.mib.2007.03.006