1
|
Affiliation(s)
- I F Zhimulev
- Institute of Cytology and Genetics, Siberian Division of Russian Academy of Sciences, Novosibirsk, Russia
| |
Collapse
|
2
|
Egyházi E, Ossoinak A, Pigon A, Holmgren C, Lee JM, Greenleaf AL. Phosphorylation dependence of the initiation of productive transcription of Balbiani ring 2 genes in living cells. Chromosoma 1996; 104:422-33. [PMID: 8601337 DOI: 10.1007/bf00352266] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Using polytene chromosomes of salivary gland cells of Chironomus tentans, phosphorylation state-sensitive antibodies and the transcription and protein kinase inhibitor 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB), we have visualized the chromosomal distribution of RNA polymerase II (pol II) with hypophosphorylated (pol IIA) and hyperphosphorylated (pol II0) carboxyl-terminal repeat domain (CTD). DRB blocks labeling of the CTD with 32Pi within minutes of its addition, and nuclear pol II0 is gradually converted to IIA; this conversion parallels the reduction in transcription of protein-coding genes. DRB also alters the chromosomal distribution of II0: there is a time-dependent clearance from chromosomes of phosphoCTD (PCTD) after addition of DRB, which coincides in time with the completion and release of preinitiated transcripts. Furthermore, the staining of smaller transcription units is abolished before that of larger ones. The staining pattern of chromosomes with anti-CTD antibodies is not detectably influenced by the DRB treatment, indicating that hypophosphorylated pol IIA is unaffected by the transcription inhibitor. Microinjection of synthetic heptapeptide repeats, anti-CTD and anti-PCTD antibodies into salivary gland nuclei hampered the transcription of BR2 genes, indicating the requirement for CTD and PCTD in transcription in living cells. The results demonstrate that in vivo the protein kinase effector DRB shows parallel effects on an early step in gene transcription and the process of pol II hyperphosphorylation. Our observations are consistent with the proposal that the initiation of productive RNA synthesis is CTD-phosphorylation dependent and also with the idea that the gradual dephosphorylation of transcribing pol II0 is coupled to the completion of nascent pol II gene transcripts.
Collapse
Affiliation(s)
- E Egyházi
- Karolinska Institutet, Department of Cell and Molecular Biology, Laboratory of Medical Cell Biology, S-171 77 Stockholm, Sweden
| | | | | | | | | | | |
Collapse
|
3
|
Microinjection of anti-topoisomerase I immunoglobulin G into nuclei of Chironomus tentans salivary gland cells leads to blockage of transcription elongation. Mol Cell Biol 1988. [PMID: 2449604 DOI: 10.1128/mcb.7.12.4308] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Purified anti-topoisomerase I immunoglobulin G (IgG) was microinjected into nuclei of Chironomus tentans salivary gland cells, and the effect on DNA transcription was investigated. Synthesis of nucleolar preribosomal 38S RNA by RNA polymerase I and of chromosomal Balbiani ring RNA by RNA polymerase II was inhibited by about 80%. The inhibitory action of anti-topoisomerase I IgG could be reversed by the addition of exogenous topoisomerase I. Anti-topoisomerase I IgG had less effect on RNA polymerase II-promoted activity of other less efficiently transcribing heterogeneous nuclear RNA genes. The pattern of inhibition of growing nascent Balbiani ring chains indicated that the transcriptional process was interrupted at the level of chain elongation. The highly decondensed state of active Balbiani ring chromatin, however, remained unaffected after injection of topoisomerase I antibodies. These data are consistent with the interpretation that topoisomerase I is an essential component in the transcriptional process but not in the maintenance of the decondensed state of active chromatin.
Collapse
|
4
|
Egyházi E, Durban E. Microinjection of anti-topoisomerase I immunoglobulin G into nuclei of Chironomus tentans salivary gland cells leads to blockage of transcription elongation. Mol Cell Biol 1987; 7:4308-16. [PMID: 2449604 PMCID: PMC368113 DOI: 10.1128/mcb.7.12.4308-4316.1987] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Purified anti-topoisomerase I immunoglobulin G (IgG) was microinjected into nuclei of Chironomus tentans salivary gland cells, and the effect on DNA transcription was investigated. Synthesis of nucleolar preribosomal 38S RNA by RNA polymerase I and of chromosomal Balbiani ring RNA by RNA polymerase II was inhibited by about 80%. The inhibitory action of anti-topoisomerase I IgG could be reversed by the addition of exogenous topoisomerase I. Anti-topoisomerase I IgG had less effect on RNA polymerase II-promoted activity of other less efficiently transcribing heterogeneous nuclear RNA genes. The pattern of inhibition of growing nascent Balbiani ring chains indicated that the transcriptional process was interrupted at the level of chain elongation. The highly decondensed state of active Balbiani ring chromatin, however, remained unaffected after injection of topoisomerase I antibodies. These data are consistent with the interpretation that topoisomerase I is an essential component in the transcriptional process but not in the maintenance of the decondensed state of active chromatin.
Collapse
Affiliation(s)
- E Egyházi
- Department of Medical Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | | |
Collapse
|
5
|
Abstract
We have used a microinjection technique to examine whether injected phosvitin, in its capacity as substrate for casein kinase NII, could compete out the endogenous phosphorylation of some nuclear phosphoproteins with regulatory potential and thereby interfere with the activity of RNA polymerase II. Phosphorylation, which utilizes ATP as phosphate donor, was separated from phosphorylation which uses GTP. Phosvitin introduced into nuclei of salivary gland cells becomes phosphorylated by the endogenous nuclear protein kinase(s) and incorporates phosphates from ATP as well as from GTP. The phosphorylation of nuclear proteins and phosvitin is heparin-sensitive, indicating that they are phosphorylated by casein kinase NII. Microinjected phosvitin does not seem to affect the incorporation of phosphate groups from ATP into nuclear proteins, but protein phosphorylation by GTP is influenced. Apart from a minor overall reduction of 32P-incorporation, the phosphorylation of a 42 kDa nuclear protein, a putative transcription stimulatory factor, and of a 115 kDa nuclear protein was competed out by 70%-80% compared with the control value obtained in the absence of phosvitin. Parallel analyses of DNA transcription in phosvitin-injected nuclei showed that the RNA polymerase II-mediated synthesis of hnRNA and Balbiani ring RNA was diminished by 80% and 90%, respectively. In contrast, the transcription of nucleolar pre-ribosomal 38 S RNA by RNA polymerase I remained unaffected. The inhibitory effect of injected phosvitin could be reversed by in vitro phosphorylation of phosvitin prior to injection, using isolated nuclei as source of protein kinase(s). Taken together, the results suggest a causal relationship between the modification of the GTP-dependent phosphorylation of specific non-histone proteins and the activity of RNA polymerase II.
Collapse
|
6
|
Egyházi E, Pigon A, Ossoinak A, Holst M, Tayip U. Phosphorylation of some chromosomal nonhistone proteins in active genes is blocked by the transcription inhibitor 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB). J Cell Biol 1984; 98:954-62. [PMID: 6699093 PMCID: PMC2113149 DOI: 10.1083/jcb.98.3.954] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The distribution of rapidly phosphorylated chromosomal proteins between chromosome I, chromosome II + III, chromosome IV, and nuclear sap including the matrix was investigated in salivary gland cells of Chironomus tentans. Chromosome IV, which carries most active nonribosomal genes in the cell, was found to be enriched in four rapidly phosphorylated nonhistone polypeptides (Mr = 25,000, 30,000, 33,000, and 42,000) in parallel with the transcriptional activity rather than with the DNA content of the chromosome. Also the histones H2A and H4 are rapidly phosphorylated but the phosphorylation is proportional to the DNA content of each chromosome sample. The 32P-labeled Mr = 42,000 polypeptide immunologically cross-reacted with an antibody elicited against the transcription stimulatory factor S-II isolated from Ehrlich ascites tumor cells (Sekimizu, K., D. Mizuno, and S. Natori, 1979, Exp. Cell Res., 124:63-72). In addition, indirect immunofluorescence studies on chromosome IV with antisera against the stimulatory factor II revealed a selective staining of the active gene loci. The incorporation of 32P into three chromosome IV nonhistone polypeptides, especially into the Mr = 42,000 polypeptide, was lowered by 70-85% shortly after administration of 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB), a likely inhibitor of heterogeneous nuclear RNA transcription at initiation level. The possibility of a causal relationship between inhibited phosphorylation of chromosomal proteins and blocked transcription of heterogeneous nuclear RNA genes by DRB is discussed.
Collapse
|
7
|
Egyházi E, Ossoinak A, Tayip U, Kazimierczuk Z, Shugar D. Specific inhibition of hnRNA synthesis by 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole. Requirement of a free 3'-hydroxyl group, but not 2'- or 5'-hydroxyls. BIOCHIMICA ET BIOPHYSICA ACTA 1982; 697:213-20. [PMID: 7104357 DOI: 10.1016/0167-4781(82)90079-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Five structural analogues of 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB), all with modified sugar moieties, have been examined for their inhibitory activities on RNA transcription in salivary glands of Chironomus tentans. The well-known ability of the parent DRB at 65 microM concentration to selectively inhibit hnRNA/mRNA synthesis by approx. 90% was essentially abolished on methylation of the 3'-OH; but, at an overdose the analogue suppressed labeling of all RNA classes examined (hnRNA/mRNA, rRNA, 4-5 S RNA) by 70-80%. By contrast, the 2'-O-methyl derivative of DRB was almost as effective as DRB itself in blocking transcription of hnRNA/mRNA genes. Blocking of both the 2' and 3' hydroxyls (2',3'-O-isopropylidene-DRB) completely abolished inhibitory activity, irrespective of the concentration employed. The 5'-deoxy-5'-chloro derivative of DRB was only slightly less effective than the parent DRB. An unusual aspect of the activities of 2'-O-methyl-DRB and 5'-deoxy-5'-chloro-DRB was their ability to stimulate synthesis of 4-5 S RNA by 25-45%. Also investigated was the influence of the various analogues on the rate of formation of [3H]UTP from [3H]uridine used as an RNA precursor. The rate of such formation of [3H]UTP was suppressed 2-6-fold by treatment with 2'-O-methyl or 3'-O-methyl-DRB, but was unaffected by 5'-deoxy-5'-chloro-DRB or 5,6-dichloro-1-alpha-D-arabinofuranosylbenzimidazole. The overall data point to the importance of a free 3'-OH in the ribose moiety of DRB for selective inhibitory activity. The alpha-D-arabinofuranosyl analogue, although less selective in inhibition of RNA transcription, still exhibits about 50% of the activity of DRB.
Collapse
|
8
|
Egyházi E, Pigon A, Rydlander L. 5,6-Dichlororibofuranosylbenzimidazole inhibits the rate of transcription initiation in intact Chironomus cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 1982; 122:445-51. [PMID: 7060585 DOI: 10.1111/j.1432-1033.1982.tb06458.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
9
|
Sass H. Effects of DMSO on the structure and function of polytene chromosomes of Chironomus. Chromosoma 1981; 83:619-43. [PMID: 7297241 DOI: 10.1007/bf00328523] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Dimethylsulfoxide (DMSO) controlled puff induction and repression (or non-induction) in larval polytene chromosomes of Chironomus tentans were studied for the case of the Balbiani rings (BR). A characteristic reaction pattern, involving BR 1, BR 2, and BR 3, all in salivary gland chromosome IV was found. In vivo exposure of 4th instar larvae (not prepupae) to 10%n DMSO at 18 degrees C first evokes an over-stimulation of BR 3 while DMSO-stimulation of puffing at BR 1 and BR 2 always follows that of BR 3. After removal of the drug, a rapid uniform collapse of all puffs occurs, thus more or less restoring the banding pattern of all previously decondensed chromosome segments. Recovery proceeds as BR's and other puffs reappear. By observing the restoration, one can locate the site from which a BR (puff) originates. BR 2, which is normally the most active non-ribosomal gene locus in untreated larvae, here serves as an example. As the sizes of BR 3, BR 1 and BR 2 change, so do the quantities of the transcriptional products in these gene loci (and vice versa), as estimated electron-microscopically in ultrathin sections and autoradiographically in squash preparations. In autoradiograms, the DMSO-stimulated BRs exhibit the most dense concentration of silver grains and therefore the highest rate of transcriptional activity. In DMSO-repressed BRs (and other puffs) the transcription of the locus specific genes is not completely shut off. In chromosomes from nuclei with high labelling intensities the repressed BRs (and other puffs) always exhibit a low level of 3H-uridine incorporation in vivo. The absence of cytologically visible BR (puff) formation therefore does not necessarily indicate complete transcriptional inactivity. Typically, before the stage of puff formation the 3H-uridine labelling first appears in the interband-like regions.
Collapse
|
10
|
Egyházi E, Holst M. Adenosine selectively inhibits labeling of chromosomal RNA, especially hnRNA, probably by acting at or near the site of chain initiation. J Cell Biol 1981; 89:1-8. [PMID: 6164679 PMCID: PMC2111770 DOI: 10.1083/jcb.89.1.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The effects of adenosine on labeling of nucleolar preribosomal RNA, chromosomal plus nuclear sap hnRNA, and 4-5S RNA in explanted salivary gland cells of chironomus tentans has been studied. Of chromosomal transcripts it is the labeling of polymerase II-promoted RNA that is interrupted preferentially, but 4-5S RNA is influenced as well. The labeling of hnRNA and 4-5S RNA is diminished by 70-90 percent and 45-60 percent, repectively, while the incorporation into the nucleolar preribosomal RNA remains essentially unchanged. Labeled adenosine is transported efficiently across the plasma membrane and becomes phosphorylated to AMP, ADP, and ATP, of which ATP predominates at noninhibitory concentrations. The rate of the formation of [(3)H]AMP is, however, enhanced in response to the increase in external adenosine doses, whereas that of [(3)H]ATP increases only slowly or remains essentially unaltered. A rise in exogenous [(3)H] adenosine concentration to 200 muM yields a [(3)H]ATP/[(3)H]AMP ratio that is about one order of magnitude lower than that at 20 muM of the nucleoside. In parallel with this, there is a gradual repression of the labeling of chromosomal RNA. A similar treatment with guanosine produces only minor reduction in GTP/GMP quotient and does not influence significantly the labeling of any sizable RNA fraction. Thus the experimental data strongly indicate that the purine ribonucleoside adenosine, but not guanosine, gives rise to a markedly diminished triphosphate/monophosphate quotient simultaneously with a selective suppression of the labeling of chromosomal RNA, especially hnRNA, when applied in overdoses. The sequence of hnRNA events during inhibition by adenosine resembles the effect of the purine nucleoside analogue 5,6-dichloro-1-beta-D- ribofuranosylbenzimidazole, indicating that the site of inhibitory action is at or close to the initiation of transcription.
Collapse
|
11
|
Jendrisak J. The use of alpha-amanitin to inhibit in vivo RNA synthesis and germination in wheat embryos. J Biol Chem 1980. [DOI: 10.1016/s0021-9258(18)43529-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
12
|
Mukherjee AS, Duttagupta AK, Chatterjee SN, Chatterjee RN, Majumdar D, Chatterjee C, Ghosh M, Achary PM, Dey A, Banerjee I. Regulation of DNA replication in Drosophila. BASIC LIFE SCIENCES 1980; 16:57-83. [PMID: 6779808 DOI: 10.1007/978-1-4684-7968-3_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
13
|
Wells DJ, Stoddard LS, Getz MJ, Moses HL. alpha-Amanitin and 5-fluorouridine inhibition of serum-stimulated DNA synthesis in quiescent AKR-2B mouse embryo cells. J Cell Physiol 1979; 100:199-214. [PMID: 159908 DOI: 10.1002/jcp.1041000202] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AKR-2B mouse embryo cells undergoing the serum-stimulated transition from a quiescent to a proliferating state exhibit an increase in the rate of hnRNA synthesis which appears to be mediated through an increase in the actual number of RNA polymerase II molecules. alpha-Amanitin, administered early in the prereplication interval following stimulation, effectively inhibits hnRNA synthesis, polysomal mRNA accumulation, polyribosome formation, and subsequent DNA synthesis, and cell division. Unexpectedly, alpha-amanitin treatment also produces almost complete inhibition of the synthesis of 45S rRNA precursor and the increase in accumulation of cytoplasmic rRNA following serum stimulation. In order to determine whether the inhibition of new ribosomal synthesis might in itself be sufficient to prevent serum-stimulated DNA synthesis, the effects of 5-fluorouridine (5-FU), a specific inhibitor of 45S rRNA processing, were investigated. If added within eight hours following serum stimulation, 5-FU was found to completely inhibit subsequent DNA synthesis. These results suggest that quiescent AKR-2B cells do not contain a sufficient excess of ribosomes to support the synthesis of proteins which are required for DNA synthesis in response to serum growth factors. Furthermore, an early polymerase II mediated synthesis of mRNA(s) coding for some factor(s) necessary for ribosomal gene transcription may be an essential step in the serum-stimulated synthesis of new ribosomes.
Collapse
|
14
|
Wieland T, Faulstich H. Amatoxins, phallotoxins, phallolysin, and antamanide: the biologically active components of poisonous Amanita mushrooms. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1978; 5:185-260. [PMID: 363352 DOI: 10.3109/10409237809149870] [Citation(s) in RCA: 372] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review gives a comprehensive account of the molecular toxicology of the bicyclic peptides obtained from the poisonous mushrooms of the genus Amanita. The discussion of the biochemical events will be preceded by a consideration of the chemistry of the toxic peptides. The structural features essential for biological activities of both the amatoxins and the phallotoxins will be discussed, also including the most important analytical data. Similar consideration will be given to antamanide, a cyclic peptide, which counteracts phalloidin. In addition, the phallolysins, three cytolytic proteins from Amanita phalloides will be discussed. The report on the biological activity of the amatoxins will deal with the sensitivity of the different RNA-polymerases towards the toxins and with their action on various cell types. Consideration will also be given to systems in which alpha-amanitin was used and can be used as a molecular tool; in the past, many investigators used the inhibitor in molecular biology, genetics, and even in physiological research. As for the phallotoxins, discussion of the affinity of these toxins for actin is provied. Further discussion attempts to understand the course of intoxication by filling in the gap between the first molecular event, formation of microfilaments, and the various lesions in hepatocytes during the intoxication.
Collapse
|
15
|
Detke S, Paule MR. DNA-dependent RNA polymerase II from Acanthamoeba castellanii. Comparison of the catalytic properties and subunit architectures of the trophozoite and cyst enzymes. BIOCHIMICA ET BIOPHYSICA ACTA 1978; 520:376-92. [PMID: 708741 DOI: 10.1016/0005-2787(78)90235-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The actively growing cells (trophozoites) of the amoeba Acanthamoeba castellanii were found to contain three or perhaps four different forms of class II DNA-dependent RNA polymerase (EC 2.7.7.6). The chromatographic and catalytic properties of all forms of the Acanthamoeba class II polymerases suggest them to be cognates of the class II polymerases previously reported. The predominant form was purified to near homogeneity and its subunit composition determined. Nine different polypeptides were found associated with the purified enzyme: 21 000; 185 000; 140 000; 70 000; 35 000; 21 000; 19 000; 18 500 and 16 200. These polypeptides were interpreted in terms of two class II RNA polymerases which differ in the molecular weight of their largest subunit. When A. castellanii is transferred to a medium lacking nutrients, the cells undergo cellular differentiation resulting in the formation of metabolically inactive cells (cyst formation). During this process there are significant changes in the RNA sequences transcribed. In contrast to this, we find that the chromatographic and catalytic properties of all of the class II RNA polymerases remain unchanged. Further, the subunit architecture of the predominant form(s) of polymerase II is unaltered. These findings suggest that although new RNA sequences are transcribed during encystment their appearance is not a consequence of extensive alterations in the subunit composition of the major class II RNA polymerase.
Collapse
|
16
|
Detke S, Stein JL, Stein GS. Synthesis of histone messenger RNAs by RNA polymerase II in nuclei from S phase HeLa S3 cells. Nucleic Acids Res 1978; 5:1515-28. [PMID: 662692 PMCID: PMC342100 DOI: 10.1093/nar/5.5.1515] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Nuclei were isolated from synchronized HeLa S3 cells and transcribed utilizing their endogenous RNA polymerases. Our data suggest that S phase nuclei are capable of synthesizing histone mRNA sequences while nuclei from G1 phase cells are not. Transcription of histone mRNA sequences by S phase nuclei can be abolished completely by low levels of alpha-amanitin (1.0 microgram/ml, a concentration which completely inhibits RNA polymerase II). From these results it appears that transcription of the histone mRNA sequences occurs during the S phase but not during the G1 phase of the cell cycle and that RNA polymerase II is responsible for histone gene readout.
Collapse
|
17
|
Detke S, Paule MR. DNA-dependent RNA polymerase I from Acanthamoeba castellanii: comparison of the catalytic properties and subunit architectures of the trophozoite and cyst enzymes. Arch Biochem Biophys 1978; 185:333-43. [PMID: 626499 DOI: 10.1016/0003-9861(78)90175-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
18
|
Sinclair GD, Brasch K. The reversible action of alpha-amanitin on nuclear structure and molecular composition. Exp Cell Res 1978; 111:1-14. [PMID: 620689 DOI: 10.1016/0014-4827(78)90230-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
19
|
|
20
|
|
21
|
Dinowitz M, Lindell TJ, O'Malley A. Altered sensitivity of Rous sarcoma virus transformed cells to inhibition of RNA synthesis by alpha-amanitin. Arch Virol 1977; 53:109-19. [PMID: 192178 DOI: 10.1007/bf01314852] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Chick embryo cells transformed by Rous sarcoma virus (RSV) continue to synthesize 40--50 percent of control amounts of RNA following 12--24 hour exposure to 2 microng/ml of the toxin whereas normal chick embryo cells similarly treated synthesize less than 5 percent of control amounts of RNA. Analysis of cells treated with alpha-amanitin, or the resistant forms I and III polymerase, do not increase in infected cells over the levels found in uninfected control cells during the first 24 hours following infection indicating that increase in polymerase levels in infected cells does not account for the observed resistance. No significant difference was detected in the sensitivity to alpha-amanitin in the form II polymerase isolated from normal and transformed cells; The greater sensitivity of normal cells to alpha-amanitin can be reduced by growing the cells at low cell density but the resistance of RSV transformed cells is not significantly altered by changes in cell density. The results suggest that the resistance of RSV transformed cells may be related to altered control of density dependent contact-inhibition of the transformed cells.
Collapse
|
22
|
Holland MJ, Hager GL, Rutter WJ. Transcription of yeast DNA by homologous RNA polymerases I and II: selective transcription of ribosomal genes by RNA polymerase I. Biochemistry 1977; 16:16-24. [PMID: 318852 DOI: 10.1021/bi00620a003] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Purified yeast DNA was transcribed by homologous RNA polymerases I and II and Escherichia coli RNA polymerase. Transcripts synthesized in vitro were analyzed by molecular hybridization with complementary DNA (cDNA) synthesized from yeast poly(A)-containing mRNA with viral reverse transcriptase and ribosomal DNA labeled in vitro by nick translation with E. coli DNA polymerase I. RNA synthesized by polymerase I and II in the presence of Mn2+ contained sequences complementary to cDNA and rDNA at a frequency consistent with random transcription of the template. Similarly, E. coli RNA polymerase synthesized an apparently random transcript in the presence of either Mn2+ or Mg2+. In contrast to these results, RNA polymerase I but not polymerase II transcripts were markedly enriched in sequences complementary to rDNA when transcription was carried out in the presence of Mg2+. The observed enrichment was 15-30-fold higher than observed for polymerase II or E. coli polymerase transcripts and is consistent with the transcript being comprised of 6-10% ribosomal sequences. These data strongly suggest that RNA polymerase I plays a critical role in selective transcription of ribosomal cistrons.
Collapse
|
23
|
Plagens U, Greenleaf AL, Bautz EK. Distribution of RNA polymerase on Drosophila polytene chromosomes as studied by indirect immunofluorescence. Chromosoma 1976; 59:157-65. [PMID: 827428 DOI: 10.1007/bf00328484] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Using indirect immunofluorescence visualization techniques we investigated the in situ distribution of RNA polymerase B on Drosophila melanogaster polytene chromosomes. The enzyme was found at many sites distributed throughout the genome in a pattern clearly distinct from that observed for histone H1, but it was especially concentrated in puffs induced by heat shock.
Collapse
|
24
|
Santelli RV, Machado-Santelli GM, Lara FJ. In vitro transcription by isolated nuclei of Rhynchosciara americana salivary glands. Characteristics of incorporation and inhibition by alpha-amanitin. Chromosoma 1976; 56:69-84. [PMID: 976015 DOI: 10.1007/bf00293731] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A method for the isolation of polytene nuclei from salivary glands cells of the Diptera Rhynchosciara americana is described. The stage-specific morphological pattern of the chromosome is maintained during the isolation. The isolated nuclei show two distinct RNA polymerase activities, namely I and II, characterized on the basis of ionic requirements and alpha-amanitin sensitivity. Studies of the product under the incubation conditions show that the system allows the synthesis of high-molecular weight RNA, beside a low molecular weight peak which may comprise pre-4S and 5S RNAs. Autoradiographic studies carried out in the presence or absence of the toxin alpha-amanitin showed that micronucleoli contain products of RNA polymerase type I activity (ribosomal RNA) and that the DNA puffs are engaged in alpha-amanitin sensitive RNA synthesis and thus are sites of polymerase type II activity.
Collapse
|
25
|
Dinowitz M. Inhibition of rous sarcoma virus by alpha-amanitin: possible role of cell DNA-dependent RNA polymerase form II. Virology 1975; 66:1-9. [PMID: 166495 DOI: 10.1016/0042-6822(75)90174-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
26
|
Egyházi E. The inhibition of nuclear RNA synthesis by the rifampicin derivative AF/013 in living cells. BIOCHIMICA ET BIOPHYSICA ACTA 1975; 378:205-15. [PMID: 1125226 DOI: 10.1016/0005-2787(75)90108-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The rifampicin derivative, AF/013, completely inhibits synthesis of the nucleolar and chromosomal RNA in explanted salivary gland cells of Chironomus tentans. When the glands are preincubated in rifampicin AF/013 for a short period before the addition of the radioactive precursors, labelling of RNA is depressed in all size classes to the same extent. In contrast, if rifampicin is replaced by the nucleoside analogue, 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole, a tentative initiation inhibitor of heterogeneous nuclear RNA, the label is reduced preferentially in the lower molecular weight region of the heterogeneous nuclear RNA spectrum. In chase type experiments, when rifampicin AF/013 is added after an initial labelling period, the synthesis of heterogeneous nuclear RNA is suppressed equally in all size classes, a result analogous to that obtained with the elongation inhibitor, alpha-amanitin. 5,6-Dichloro-1-beta-D-ribofuranosylbenzimidazole, under similar chase conditions, preferentially inhibits the labelling of smaller heterogeneous nuclear RNA molecules, but later on abolishes labelling of molecules with higher S values, also. Rifampicin AF/013 prevents or affects seriously the normal processing of the prelabelled preribosomal RNA in the nucleolus. It further interferes with the export of nuclear RNA to the cytoplasm, and/or promotes a non-physiological breakdown of cytoplasmic RNA. The experimental data suggest that rifampicin AF/013 acts on RNA synthesis in living cells by interference with chain elongation.
Collapse
|
27
|
|
28
|
Kedinger C, Simard R. The action of alpha-amanitin on RNA synthesis in Chinese hamster ovary cells. Ultrastructural and biochemical studies. J Cell Biol 1974; 63:831-42. [PMID: 4474178 PMCID: PMC2109362 DOI: 10.1083/jcb.63.3.831] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
alpha-Amanitin acts in vitro as a selective inhibitor of the nucleoplasmic form B RNA polymerases. Treatment of Chinese hamster ovary (CHO) cells with this drug leads principally to a severe fragmentation of the nucleoli. While the ultrastructural lesions induced by alpha-amanitin in CHO cells and in rat or mouse liver are quite similar, the results diverge concerning the effect on RNA synthesis. It has been shown that in rat or mouse liver alpha-amanitin blocks both extranucleolar and nucleolar RNA synthesis. Our autoradiographic and biochemical evidence indicates that in CHO cells high molecular weight extranucleolar RNA synthesis (HnRNA) is blocked by the alpha-amanitin treatment, whereas nucleolar RNA (preribosomal RNA) synthesis remains unaffected even several hours after the inhibition of extranucleolar RNA synthesis. Furthermore, the processing of this RNA as well as its transport to the cytoplasm seem only slightly affected by the treatment. Finally, under these conditions, the synthesis of the low molecular RNA species (4-5S) still occurs, though less actively. The results are interpreted as evidence for a selective impairment of HnRNA synthesis by alpha-amanitin in CHO cells.
Collapse
|
29
|
|
30
|
|
31
|
|
32
|
Mauck JC, Green H. Regulation of RNA synthesis in fibroblasts during transition from resting to growing state. Proc Natl Acad Sci U S A 1973; 70:2819-22. [PMID: 4517934 PMCID: PMC427116 DOI: 10.1073/pnas.70.10.2819] [Citation(s) in RCA: 101] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Addition of serum, containing fibroblast growth factors, to a culture of resting 3T6 cells stimulates a transition to the growing state. Studies of ghost monolayers prepared with the aid of detergent at intervals after stimulation showed an increase in the rate of ribosomal RNA synthesis within 10 min. The rate continued to increase for many hours and reached a level 2.5- to 3.5-fold higher by the time DNA synthesis began. The increasing rate of ribosomal RNA synthesis appeared independent of an increase in the number of ribosomal genes, since it was not affected by prevention of DNA synthesis with cytosine arabinoside. In contrast to ribosomal RNA, the overall rate of transscription of heterogeneous nuclear RNA was not directly affected by serum growth factors and does not appear to be regulated during the transition from resting to growing state. It seems, instead, to be fixed in relation to the amount of template, for it increases proportionally to DNA content.
Collapse
|
33
|
Brändle E, Zetsche K. [Localisation of the α-amanitin-sensitive RNA-polymerase in nuclei of Acetabularia]. PLANTA 1973; 111:209-217. [PMID: 24469574 DOI: 10.1007/bf00385105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/1973] [Indexed: 06/03/2023]
Abstract
An isolation medium for nuclei of Acetabularia mediterranea is described. The medium offers the possibility to keep nuclei alive (verified by reimplantation) for at least 10 min and to obtain nuclei with radioactively labelled RNA.The influence of α-amanitin on nucleolar and nucleoplasmatic RNA-synthesis is investigated autoradiographically. Amanitin inhibits the incorporation of uridine into the nucleoplasmatic RNA, whereas incorporation into the RNA of nucleoli is hardly or not at all influenced.We conclude that, in agreement with findings on animal cells, α-amanitin inhibits at least one of the RNA-polymerases localized in the nucleoplasm but does not markedly influence the RNA-polymerase of the nucleoli.
Collapse
Affiliation(s)
- E Brändle
- Institut für Biologie, Universität, Auf der Morgenstelle, D-7400, Tübingen, Federal Republic of Germany
| | | |
Collapse
|
34
|
Schmid W, Sekeris CE. Sequential stimulation of extranucleolar and nucleolar RNA synthesis in rat liver by cortisol. FEBS Lett 1972; 26:109-12. [PMID: 4636718 DOI: 10.1016/0014-5793(72)80553-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
|