Journal ArticleDOI
Biological Sciences: Specific Action of α-Amanitin on Mammalian RNA Polymerase Protein
TLDR
MOST inhibitors of RNA synthesis act on the DNA template rather than directly on the polymerizing enzyme, so the bacterial polymerase but not the animal polymerase is inhibited by the rifamycins11, streptovaricin12 and probably streptolydigin13.Abstract:
MOST inhibitors of RNA synthesis act on the DNA template rather than directly on the polymerizing enzyme. Antibiotics that inhibit RNA synthesis by binding to DNA include actinomycin D1, miracil D2, nogalomycin3, chromomycin A34, aflatoxin5, echinomycin, daunomycin, mithramycin and olivomycin6, ethidium bromide7, pro-flavine8, nitrogen mustard9 and acetylaminofluorene10. In each case tested, there is evidence that the antibiotic can inhibit RNA synthesis in both animal and bacterial cells, a finding to be expected because the site of the inhibitory action is the DNA template and not the enzyme. On the other hand, a few antibiotics are known to react with the enzyme molecule itself and these are more species selective. The bacterial polymerase but not the animal polymerase is inhibited by the rifamycins11, streptovaricin12 and probably streptolydigin13. Rifamycin has been shown to bind stoichiometrically to the bacterial enzyme molecule and to prevent initiation14, whereas streptolydigin appears to inhibit chain elongation13.read more
Citations
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Journal ArticleDOI
Specific Inhibition of Nuclear RNA Polymerase II by α-Amanitin
TL;DR: α-Amanitin, a toxic substance from the mushroom Amanita phalloides, is a potent inhibitor of DNA-dependent RNA polymerase II (the nucleoplasmic form) from sea urchin, rat liver, and calf thymus.
Journal ArticleDOI
Amatoxins, phallotoxins, phallolysin, and antamanide: the biologically active components of poisonous Amanita mushrooms.
Theodor Wieland,Heinz Faulstich +1 more
TL;DR: This review gives a comprehensive account of the molecular toxicology of the bicyclic peptides obtained from the poisonous mushrooms of the genus Amanita, also including the most important analytical data.
Journal ArticleDOI
Animal DNA-dependent RNA polymerases 11. Mechanism of the inhibition of RNA polymerases B by amatoxins
M. Cochet-Meilhac,Pierre Chambon +1 more
TL;DR: Hydrogen bonds seem to play an essential role in the stability of amatoxin—enzymes B complex as suggested by the values of the thermodynamic parameters and by the study of the dissociation rate constant of complexes between enzymes B and various amatoxins, differing only in the structure of their hydroxylated isoleucine side-chain.
Journal ArticleDOI
Transition from non-motile behaviour to directed migration during early PGC development in zebrafish.
Heiko Blaser,Silke Eisenbeiss,Marc Neumann,Michal Reichman-Fried,Bernard Thisse,Christine Thisse,Erez Raz +6 more
TL;DR: It is shown that the PGCs acquire competence to respond to the chemokine following discrete maturation steps, and this transition depends on zygotic transcription and on the function of the RNA-binding protein Dead end and is correlated with down regulation of the cell adhesion molecule E-cadherin.
Journal ArticleDOI
Triptolide is an inhibitor of RNA polymerase I and II–dependent transcription leading predominantly to down-regulation of short-lived mRNA
Stéphane Vispé,Luc DeVries,Laurent Créancier,Jérome Besse,Sophie Bréand,David J. Hobson,Jesper Q. Svejstrup,Jean-Philippe Annereau,Didier Cussac,Charles Dumontet,Nicolas Guilbaud,Jean-Marc Barret,Christian Bailly +12 more
TL;DR: It is concluded that triptolide is an original pharmacologic inhibitor of RNA polymerase activity, affecting indirectly the transcription machinery, leading to a rapid depletion of short-lived mRNA, including transcription factors, cell cycle regulators, and the oncogenes MYC and Src.
References
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Journal ArticleDOI
Complex formation between ethidium bromide and nucleic acids.
TL;DR: The interaction between ethidium bromide and nucleic acids shows a pronounced metachromatic effect which has been used to obtain quantitative data on the process of complex formation and is shown to be reversible in solution by demonstrating an exchange reaction between free and bound ethidium.
Journal ArticleDOI
Base Specificity in the Interaction of Polynucleotides with Antibiotic Drugs
TL;DR: Chromomycin and olivomycin form complexes with DNA, preferably in the helical form, but not with RNA, and none of the other antibiotics requires the presence of any single base in the template for its action.
Book ChapterDOI
Actinomycin and Nucleic Acid Function
E. Reich,Irving H. Goldberg +1 more
TL;DR: A model recently proposed for the reaction of actinomycin with DNA and to the implications of this model for the template function of helical nucleic acids for the role of RNA metabolism in many systems is related particularly to this discussion.
Journal ArticleDOI
Cyclic re-use of the RNA polymerase sigma factor.
TL;DR: The RNA polymerase σ factor is required for the initiation of RNA synthesis and may be re-used by another polymerase molecule to initiate a new RNA chain.
Journal ArticleDOI
Studies on the stimulation by ammonium sulphate of the DNA-dependent RNA polymerase of isolated rat-liver nuclei.
C.C. Widnell,Jamshed R. Tata +1 more
TL;DR: It is inferred that nuclei incubated in the absence of ammonium sulphate may synthesize ribosomal RNA, and that the action of ammonia sulphate is to induce the synthesis of an RNA more DNA-like in its base composition.