1
|
Cellini A, Scoarughi GL, Poggiali P, Santino I, Sessa R, Donini P, Cimmino C. Stringent control in the archaeal genus Sulfolobus. Res Microbiol 2004; 155:98-104. [PMID: 14990261 DOI: 10.1016/j.resmic.2003.11.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2003] [Accepted: 11/11/2003] [Indexed: 10/26/2022]
Abstract
Six Archaea belonging to the phylum Euryarchaeota were previously analyzed with respect to stringent control. Only one of the strains studied was shown to possess Bacteria-like stringent control over stable RNA accumulation; ppGpp and pppGpp production was totally lacking in all Archaea analyzed. To broaden our knowledge of stringent control in the Archaea, we examined here the accumulation of stable RNA and the production of ppGpp and pppGpp under amino acid starvation in three species of the genus Sulfolobus belonging to the Crenarchaeota, an archaeal phylum distant from the Euryarchaeota. In these species the accumulation of sRNA was arrested when aminoacylation of tRNA was inhibited by pseudomonic acid. Furthermore, stringent control of stable RNA accumulation was relaxed by some protein synthesis inhibitors that do not interfere with aminoacylation of tRNA, a feature typical of bacterial stringent control. Neither ppGpp nor pppGpp could be detected during growth or under amino acid starvation, and the intracellular GTP levels did not decrease in the course of the stringent response. These results show that: (1) stringency is widespread in wild-type thermoacidophilic archaea; (2) in the crenarchaeal species analyzed here SC depends on the deaminoacylation of tRNA; (3) in the strains analyzed ppGpp is not produced during normal growth nor during the stringent reaction; it is therefore not an effector either of SC over sRNA synthesis or of growth control. (p)ppGpp appears to be completely absent from the Archaea and thus constitutes an additional feature that distinguishes the Bacteria from the Archaea.
Collapse
Affiliation(s)
- Andrea Cellini
- Dipartimento di Biologia Cellulare e dello Sviluppo, Università La Sapienza, Via dei Sardi 70, 00185 Rome, Italy
| | | | | | | | | | | | | |
Collapse
|
2
|
Stoyanova BB, Dabeva MD. Ribosomal RNA precursor transcription in rat liver is not dependent on continuous synthesis of proteins. BIOCHIMICA ET BIOPHYSICA ACTA 1980; 608:358-67. [PMID: 7397190 DOI: 10.1016/0005-2787(80)90181-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effect of inhibition of protein synthesis by cycloheximide on rRNA precursor transcription in rat liver was analyzed. Two doses of the drug were studied: low, 5 mg/kg, and high, 20 mg/kg. Both doses of cycloheximide cause rapid, complete and continuous inhibition of protein synthesis. The low dose of the antibiotic does not alter the rRNA precursor transcription for at least 4 h, while the high dose, which is lethal to rats, leads gradually to suppression of rRNA precursor synthesis. It is shown that the high dose of cycloheximide causes profound changes in the metabolism of the free nucleotides and drastic inhibition of [14C]orotate and [32P]orthophosphate uptake into the pool of free nucleotides. It is supposed that the strong side-effects of cycloheximide, rather than the cessation of protein synthesis, are responsible for the observed inhibition of rRNA precursor synthesis. It is concluded that rRNA precursor transcription is not regulated by rapidly turning-over protein(s).
Collapse
|
3
|
Langford CJ, Scheffer JW, Jeffrey PL, Austin L. The in vitro synthesis of RNA within the rat nodose ganglion following vagotomy. J Neurochem 1980; 34:531-9. [PMID: 7354327 DOI: 10.1111/j.1471-4159.1980.tb11177.x] [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: 01/24/2023]
|
4
|
|
5
|
Ray DB, Butow RA. Regulation of mitochondrial ribosomal RNA synthesis in yeast. II. Effects of temperature sensitive mutants defective in cytoplasmic protein synthesis. MOLECULAR & GENERAL GENETICS : MGG 1979; 173:239-47. [PMID: 384148 DOI: 10.1007/bf00268634] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
6
|
Ray DB, Butow RA. Regulation of mitochondrial ribosomal RNA synthesis in yeast. I. In search of a relaxation of stringency. MOLECULAR & GENERAL GENETICS : MGG 1979; 173:227-38. [PMID: 384147 DOI: 10.1007/bf00268633] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Studies were undertaken to determine if mitochondrial rRNA synthesis in yeast is regulated by general cellular stringent control mechanism. Those variables affecting the relaxation of a cycloheximide-induced stringent response as a result of medium-shift-down or tyrosine limitation include: 1) the stage of cell growth, 2) carbon source, 3) strain differences and, 4) integrity of the cell wall. The extent of phenotypic relaxation decreased or was eliminated entirely in a strain dependent manner as cells entered stationary phase of growth or by growth of cells on galactose or in osmotically stabilized spheroplast cultures. Cytoplasmic and mitochondrial RNA species were extracted from regrowing spheroplast cultures subjected to different experimental regimens and analyzed by electrophoresis on 2.5% polyacrylamide gels. Relative rates of synthesis were determined in pulse experiments and normalized by double-label procedures to longterm label material. Tyrosine starvation was found to inhibit synthesis of the large and small rRNA species of both cytoplasmic and mitochondrial rRNAs to about 5-20% of the control values. Chloramphenicol inhibits mitochondrial and cytoplasmic rRNA synthesis to 60-80% of control; however, chloramphenicol addition does not relax the stringent inhibition of either class of rRNAs. Cycloheximide addition results in 70-80% inhibition of synthesis of both cellular speceis of rRNAs. As noted above, cycloheximide does not relax the stringent response of cytoplasmic rRNA synthesis in spheroplasts, and also does not relax the stringent inhibition of mitochondrial rRNA synthesis. From these studies, we conclude that both cytoplasmic and mitochondrial rRNA synthesis share common control mechanisms related to regulation of protein synthesis by shift-down or amino acid limitation.
Collapse
|
7
|
Ramagopal S, Marcus A. RNA synthesis in growing and stationary cells of a culture of Scarlet Rose. Disproportionate synthesis of ribosomal subunits in the stationary state. J Cell Physiol 1979; 98:603-11. [PMID: 438304 DOI: 10.1002/jcp.1040980318] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
RNA synthesis has been investigated in resting and growing cells of a culture of Scarlet rose. The rates of messenger RNA (mRNA) and ribosomal RNA (rRNA) synthesis are five- and ten-fold higher, respectively, in the growing culture. In stationary phase cultures, newly synthesized 26S and 18S rRNA do not appear in the cytoplasm in equimolar amounts. Rather, the 26S/18S ratio of [3H]-uridine labeled rRNA of stationary cells ranged from 0.9 to 1.3 while the ratio of the corresponding fraction from growing cells was 1.6 to 2.0. A similar result was obtained when cells were labeled with [3H-CH3] methionine. Pulse chase experiments demonstrated that the nascent pre-rRNA in resting cells could be chased into polysomes. These data are interpreted to indicate that a major part of the regulation of rRNA synthesis in stationary cells is at the level of the processing of the rRNA transcript.
Collapse
|
8
|
Eikhom TS, Nissen-Meyer J, Vangdal E, Abraham KA. A growth-dependent excess of 40 S ribosomal subunits in plasmacytoma cells grown in suspension culture. Exp Cell Res 1978; 112:257-64. [PMID: 631220 DOI: 10.1016/0014-4827(78)90208-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
9
|
Grummt I. The effects of histidine starvation on the methylation of ribosomal RNA. EUROPEAN JOURNAL OF BIOCHEMISTRY 1977; 79:133-41. [PMID: 913415 DOI: 10.1111/j.1432-1033.1977.tb11791.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The effect of amino acid starvation on the control of ribosome biosynthesis at the post-transcriptional level has been studied in Ehrlich ascites cells. A comparison of the turnover rates of ribosomal precursor RNA (pre-rRNA) and the degree of methylation of ribosomal RNA after histidine deprivation revealed that the slow down of ribosome formation is accompanied by a significant inhibition of rRNA methylation. Analysis of nucleolar and cytoplasmic RNA double-labelled with L-[Me-3H]methionine and [14C]uridine, as well as a quantitative determination of alkali-stable dinucleotides on DEAE-Sephadex, showed that methylation of rRNA species was inhibited by about 50% under shift-down conditions. This decrease in RNA methylation does not reflect an inhibition of rRNA methylases caused by amino acid starvation but is rather brought about by a shrinkage in the pool size of S-adenosylmethionine, the donor of methyl groups. It is suggested that amino acid starvation might exert its blocking effect on proper ribosome maturation by affecting the methylation of 45-S RNA.
Collapse
|
10
|
Dehlinger PJ, Hamilton TA, Litt M. Amino acid control of stable RNA synthesis in Friend leukemia cells in relation to intracellular purine nucleoside triphosphate levels. EUROPEAN JOURNAL OF BIOCHEMISTRY 1977; 77:495-9. [PMID: 268284 DOI: 10.1111/j.1432-1033.1977.tb11691.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Histidinol is known to cause deacylation of histidyl-tRNA in cultured mammalian cells, thereby producing a functional deprivation of histidine. Such deprivation of an essential amino acid is known to produce various effects, including inhibition of tRNA synthesis and of nucleolar RNA synthesis and processing. It has been proposed [Grummt, F. & Grummt, I. (1976) Eur. J. Biochem. 64, 307-312] that this response to amino acid deprivation is mediated by decreases in GTP and ATP pool sizes caused by a deacylated-tRNA-dependent hydrolysis of GTP. In contrast, we find that Friend leukemia cells treated with histidinol show no significant changes in GTP or ATP pool sizes, although this treatment does produce the expected inhibition of rRNA and tRNA synthesis.
Collapse
|
11
|
Jacob ST, Rose KM, Munro HN. Response of poly(adenylic acid) polymerase in rat liver nuclei and mitochondria to stravation and re-feeding with amino acids. Biochem J 1976; 158:161-7. [PMID: 985420 PMCID: PMC1163955 DOI: 10.1042/bj1580161] [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: 12/25/2022]
Abstract
Poly(adenylic acid) polymerase was extracted from liver nuclei and mitochondria of rats either fed ad libitum, starved overnight or starved and then re-fed with a complete amino acid mixture for 1-3 h. The enzymes were partially purified and assayed by using exogenous primers. Starvation resulted in an 80% decrease in the total activity of the purified nuclear enzyme, and the mitochondrial enzyme activity diminished to almost zero after overnight starvation. Measurements of the protein content of whole nuclei or mitochondria and of the enzyme extracts from these organelles indicated that the decrease in enzyme activity on starvation was not caused by incomplete extraction of the enzyme from the starved animals. Re-feeding the animals with the complete amino acid mixture increased the total activity of poly(A) polymerase from the nuclei and mitochondria by 1.9-fold and 63-fold respectively. Under these conditions, the total protein content of the nuclei and mitochondria increased by only 13 and 32% respectively. These data indicate that poly(A) polymerase is one of the cellular proteins specifically regulated by amino acid supply.
Collapse
|
12
|
Hamilton TA, Litt M. Biosynthesis of mammalian transfer RNA. Evidence for regulation by deacylated transfer RNA. BIOCHIMICA ET BIOPHYSICA ACTA 1976; 435:362-75. [PMID: 986171 DOI: 10.1016/0005-2787(76)90202-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The rate of tRNA synthesis in cultured Friend leukemia cells has been examined as a function of the variation in polyribosome structure produced by treatment with a variety of inhibitors of protein synthesis. The results indicate, in contrast to the conclusions of Bölcsföldi (Bölcsföldi, G. (1974) Exp. Cell Res., 88, 231--240), that no necessary relationship exists between the ribosome distribution and the rate of tRNA synthesis. Alternatively, it is observed that inhibitors of tRNA aminoacylation cause, in all cases, a decrease in the rate of tRNA synthesis whereas drugs which may stimulate the aminoacylation of tRNA cause, in all cases, an elevation of the rate of tRNA synthesis. It is concluded that tRNA synthesis in mammalian cells may be regulated by the relative levels of acylated and deacylated tRNA.
Collapse
|
13
|
Scheer U, Trendelenburg MF, Franke WW. Regulation of transcription of genes of ribosomal rna during amphibian oogenesis. A biochemical and morphological study. J Cell Biol 1976; 69:465-89. [PMID: 1262400 PMCID: PMC2109682 DOI: 10.1083/jcb.69.2.465] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Natural changes in the transcription of rRNA genes were studied in nucleoli from three oogenic stages of the newt Triturus alpestris with electron microscope, auto-radiographic, and biochemical techniques. From determinations of the uridine triphosphate pool sizes and [3H]uridine uptake, phosphorylation, and incorporation into 28S and 18S rRNAs in vivo it was estimated that the rate of rRNA synthesis was about 0.01% in previtellogenic oocytes and 13% in mature oocytes when compared to midvitellogenesis. Spread preparations of nucleoli showed significant morphological changes in the transcriptional complexes. The total number of lateral fibrils, i.e., ribonucleoproteins containing the nascent rRNA precursor, were drastically decreased in stages of reduced synthetic activity. This indicates that rRNA synthesis is regulated primarily at the level of transcription. The resulting patterns of fibril coverage of the nucleolar chromatin axes revealed a marked heterogeneity. On the same nucleolar axis occurred matrix units that were completely devoid of lateral fibrils, matrix units that were almost fully covered with lateral fibrils, and various forms of matrix units with a range of lateral fibril densities intermediate between the two extremes. Granular particles that were tentatively identified as RNA polymerase molecules were not restricted to the transciptional complexes. They were observed, although less regularly and separated by greater distances, in untranscribed spacer regions as well as in untranscribed gene intercepts. The results show that the pattern of transcriptional control of rRNA genes differs widely in different genes, even in the same genetic unit.
Collapse
|
14
|
Nissen-Meyer J, Eikhom TS. An excess of the small ribosomal subunits and a higher rate of turnover of the 60 S than of the 40 S ribosomal subunits in L cells grown in suspension culture. J Mol Biol 1976; 101:211-21. [PMID: 1263258 DOI: 10.1016/0022-2836(76)90373-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|
15
|
|
16
|
Segal DJ, McCoy EE. Studies on Down's syndrome in tissue culture. I. Growth rates and protein contents of fibroblast cultures. J Cell Physiol 1974; 83:85-90. [PMID: 4273197 DOI: 10.1002/jcp.1040830112] [Citation(s) in RCA: 97] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
17
|
|