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Staudacher J, Rebnegger C, Gasser B. Treatment with surfactants enables quantification of translational activity by O-propargyl-puromycin labelling in yeast. BMC Microbiol 2021; 21:120. [PMID: 33879049 PMCID: PMC8056590 DOI: 10.1186/s12866-021-02185-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 04/08/2021] [Indexed: 11/10/2022] Open
Abstract
Background Translation is an important point of regulation in protein synthesis. However, there is a limited number of methods available to measure global translation activity in yeast. Recently, O-propargyl-puromycin (OPP) labelling has been established for mammalian cells, but unmodified yeasts are unsusceptible to puromycin. Results We could increase susceptibility by using a Komagataella phaffii strain with an impaired ergosterol pathway (erg6Δ), but translation measurements are restricted to this strain background, which displayed growth deficits. Using surfactants, specifically Imipramine, instead, proved to be more advantageous and circumvents previous restrictions. Imipramine-supplemented OPP-labelling with subsequent flow cytometry analysis, enabled us to distinguish actively translating cells from negative controls, and to clearly quantify differences in translation activities in different strains and growth conditions. Specifically, we investigated K. phaffii at different growth rates, verified that methanol feeding alters translation activity, and analysed global translation in strains with genetically modified stress response pathways. Conclusions We set up a simple protocol to measure global translation activity in yeast on a single cell basis. The use of surfactants poses a practical and non-invasive alternative to the commonly used ergosterol pathway impaired strains and thus impacts a wide range of applications where increased drug and dye uptake is needed. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02185-3.
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Affiliation(s)
- Jennifer Staudacher
- Christian Doppler Laboratory for Growth-decoupled Protein Production in Yeast, Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria.,Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria
| | - Corinna Rebnegger
- Christian Doppler Laboratory for Growth-decoupled Protein Production in Yeast, Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria.,Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria
| | - Brigitte Gasser
- Christian Doppler Laboratory for Growth-decoupled Protein Production in Yeast, Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Vienna, Austria. .,Institute of Microbiology and Microbial Biotechnology, Department of Biotechnology, BOKU University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.
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2
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Jungfleisch J, Nedialkova DD, Dotu I, Sloan KE, Martinez-Bosch N, Brüning L, Raineri E, Navarro P, Bohnsack MT, Leidel SA, Díez J. A novel translational control mechanism involving RNA structures within coding sequences. Genome Res 2016; 27:95-106. [PMID: 27821408 PMCID: PMC5204348 DOI: 10.1101/gr.209015.116] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 11/03/2016] [Indexed: 12/20/2022]
Abstract
The impact of RNA structures in coding sequences (CDS) within mRNAs is poorly understood. Here, we identify a novel and highly conserved mechanism of translational control involving RNA structures within coding sequences and the DEAD-box helicase Dhh1. Using yeast genetics and genome-wide ribosome profiling analyses, we show that this mechanism, initially derived from studies of the Brome Mosaic virus RNA genome, extends to yeast and human mRNAs highly enriched in membrane and secreted proteins. All Dhh1-dependent mRNAs, viral and cellular, share key common features. First, they contain long and highly structured CDSs, including a region located around nucleotide 70 after the translation initiation site; second, they are directly bound by Dhh1 with a specific binding distribution; and third, complementary experimental approaches suggest that they are activated by Dhh1 at the translation initiation step. Our results show that ribosome translocation is not the only unwinding force of CDS and uncover a novel layer of translational control that involves RNA helicases and RNA folding within CDS providing novel opportunities for regulation of membrane and secretome proteins.
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Affiliation(s)
- Jennifer Jungfleisch
- Molecular Virology Group, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, 08003 Barcelona, Spain
| | - Danny D Nedialkova
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, 48149 Münster, Germany.,Cells-in-Motion Cluster of Excellence, University of Münster, 48149 Münster, Germany
| | - Ivan Dotu
- Research Programme on Biomedical Informatics (GRIB), Department of Experimental and Health Sciences, Universitat Pompeu Fabra, Hospital del Mar Medical Research Institute (IMIM), 08003 Barcelona, Spain
| | - Katherine E Sloan
- Institute for Molecular Biology, Göttingen University Medical Department, 37073 Göttingen, Germany
| | - Neus Martinez-Bosch
- Program of Cancer Research, Hospital del Mar Medical Research Institute (IMIM), 08003 Barcelona, Spain
| | - Lukas Brüning
- Institute for Molecular Biology, Göttingen University Medical Department, 37073 Göttingen, Germany
| | - Emanuele Raineri
- Statistical Genomics, Centro Nacional de Analisis Genomica, 08028 Barcelona, Spain
| | - Pilar Navarro
- Program of Cancer Research, Hospital del Mar Medical Research Institute (IMIM), 08003 Barcelona, Spain
| | - Markus T Bohnsack
- Institute for Molecular Biology, Göttingen University Medical Department, 37073 Göttingen, Germany.,Göttingen Center for Molecular Biosciences, Georg-August University, 37073 Göttingen, Germany
| | - Sebastian A Leidel
- Max Planck Research Group for RNA Biology, Max Planck Institute for Molecular Biomedicine, 48149 Münster, Germany.,Cells-in-Motion Cluster of Excellence, University of Münster, 48149 Münster, Germany.,Faculty of Medicine, University of Münster, 48149 Münster, Germany
| | - Juana Díez
- Molecular Virology Group, Department of Experimental and Health Sciences, Universitat Pompeu Fabra, 08003 Barcelona, Spain
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3
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Citterio B, Albertini MC, Ghibelli L, Falcieri E, Battistelli M, Canonico B, Rocchi MBL, Teodori L, Ciani M, Piatti E. Multiparameter analysis of apoptosis in puromycin-treated Saccharomyces cerevisiae. Arch Microbiol 2015; 197:773-80. [PMID: 25868793 DOI: 10.1007/s00203-015-1110-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 04/01/2015] [Accepted: 04/02/2015] [Indexed: 01/07/2023]
Abstract
In Saccharomyces cerevisiae, a typical apoptotic phenotype is induced by some stress factors such as sugars, acetic acid, hydrogen peroxide, aspirin and age. Nevertheless, no data have been reported for apoptosis induced by puromycin, a damaging agent known to induce apoptosis in mammalian cells. We treated S. cerevisiae with puromycin to induce apoptosis and evaluated the percentage of dead cells by using Hoechst 33342 staining, transmission electron microscopy (TEM) and Annexin V flow cytometry (FC) analysis. Hoechst 33342 fluorescence images were processed to acquire parameters to use for multiparameter analysis [and perform a principal component analysis, (PCA)]. Cell viability was evaluated by Rhodamine 123 (Rh 123) and Acridine Orange microscope fluorescence staining. The results show puromycin-induced apoptosis in S. cerevisiae, and the PCA analysis indicated that the increasing percentage of apoptotic cells delineated a well-defined graph profile. The results were supported by TEM and FC. This study gives new insights into yeast apoptosis using puromycin as inducer agent, and PCA analysis may complement molecular analysis facilitating further studies to its detection.
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Affiliation(s)
- Barbara Citterio
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
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4
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Cary GA, Yoon SH, Torres CG, Wang K, Hays M, Ludlow C, Goodlett DR, Dudley AM. Identification and characterization of a drug-sensitive strain enables puromycin-based translational assays in Saccharomyces cerevisiae. Yeast 2014; 31:167-78. [PMID: 24610064 DOI: 10.1002/yea.3007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 02/27/2014] [Accepted: 03/03/2014] [Indexed: 11/11/2022] Open
Abstract
Puromycin is an aminonucleoside antibiotic with structural similarity to aminoacyl tRNA. This structure allows the drug to bind the ribosomal A site and incorporate into nascent polypeptides, causing chain termination, ribosomal subunit dissociation and widespread translational arrest at high concentrations. In contrast, at sufficiently low concentrations, puromycin incorporates primarily at the C-terminus of proteins. While a number of techniques utilize puromycin incorporation as a tool for probing translational activity in vivo, these methods cannot be applied in yeasts that are insensitive to puromycin. Here, we describe a mutant strain of the yeast Saccharomyces cerevisiae that is sensitive to puromycin and characterize the cellular response to the drug. Puromycin inhibits the growth of yeast cells mutant for erg6∆, pdr1∆ and pdr3∆ (EPP) on both solid and liquid media. Puromycin also induces the aggregation of the cytoplasmic processing body component Edc3 in the mutant strain. We establish that puromycin is rapidly incorporated into yeast proteins and test the effects of puromycin on translation in vivo. This study establishes the EPP strain as a valuable tool for implementing puromycin-based assays in yeast, which will enable new avenues of inquiry into protein production and maturation.
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Affiliation(s)
- Gregory A Cary
- Institute for Systems Biology, Seattle, WA, USA; Molecular and Cellular Biology Program, University of Washington, Seattle, WA, USA
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5
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Ding B, LeJeune D, Li S. The C-terminal repeat domain of Spt5 plays an important role in suppression of Rad26-independent transcription coupled repair. J Biol Chem 2009; 285:5317-26. [PMID: 20042611 DOI: 10.1074/jbc.m109.082818] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
In eukaryotic cells, transcription coupled nucleotide excision repair (TCR) is believed to be initiated by RNA polymerase II (Pol II) stalled at a lesion in the transcribed strand of a gene. Rad26, the yeast homolog of the human Cockayne syndrome group B (CSB) protein, plays an important role in TCR. Spt4, a transcription elongation factor that forms a complex with Spt5, has been shown to suppress TCR in rad26Delta cells. Here we present evidence that Spt4 indirectly suppresses Rad26-independent TCR by protecting Spt5 from degradation and stabilizing the interaction of Spt5 with Pol II. We further found that the C-terminal repeat (CTR) domain of Spt5, which is dispensable for cell viability and is not involved in interactions with Spt4 and Pol II, plays an important role in the suppression. The Spt5 CTR is phosphorylated by the Bur kinase. Inactivation of the Bur kinase partially alleviates TCR in rad26Delta cells. We propose that the Spt5 CTR suppresses Rad26-independent TCR by serving as a platform for assembly of a multiple protein suppressor complex that is associated with Pol II. Phosphorylation of the Spt5 CTR by the Bur kinase may facilitate the assembly of the suppressor complex.
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Affiliation(s)
- Baojin Ding
- Department of Comparative Biomedical Sciences, Louisiana State University, Baton Rouge, Louisiana 70803, USA
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6
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Teng J, Goto R, Iida K, Kojima I, Iida H. Ion-channel blocker sensitivity of voltage-gated calcium-channel homologue Cch1 in Saccharomyces cerevisiae. Microbiology (Reading) 2008; 154:3775-3781. [DOI: 10.1099/mic.0.2008/021089-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Jinfeng Teng
- Laboratory of Cell Biology, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma 371-8510, Japan
- Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei-shi, Tokyo 184-8501, Japan
| | - Rika Goto
- Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei-shi, Tokyo 184-8501, Japan
| | - Kazuko Iida
- Biomembrane Signaling Project 2, Tokyo Metropolitan Institute of Medical Science, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo 113-8613, Japan
| | - Itaru Kojima
- Laboratory of Cell Biology, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi, Gunma 371-8510, Japan
| | - Hidetoshi Iida
- Department of Bioenvironmental Science, Okazaki Institute for Integrative Bioscience, National Institutes of Natural Sciences, Higashiyama 5-1, Myodaiji, Okazaki, Aichi 444-8787, Japan
- Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei-shi, Tokyo 184-8501, Japan
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7
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Chen X, Ruggiero C, Li S. Yeast Rpb9 plays an important role in ubiquitylation and degradation of Rpb1 in response to UV-induced DNA damage. Mol Cell Biol 2007; 27:4617-25. [PMID: 17452455 PMCID: PMC1951484 DOI: 10.1128/mcb.00404-07] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Revised: 04/09/2007] [Accepted: 04/11/2007] [Indexed: 01/28/2023] Open
Abstract
Rpb9, a nonessential subunit of RNA polymerase II (Pol II), has multiple transcription-related functions in Saccharomyces cerevisiae, including transcription elongation and transcription-coupled repair (TCR). Here we show that, in response to UV radiation, Rpb9 also functions in promoting ubiquitylation and degradation of Rpb1, the largest subunit of Pol II. This function of Rpb9 is not affected by any pathways of nucleotide excision repair, including TCR mediated by Rpb9 itself and by Rad26. Rpb9 is composed of three distinct domains: the N-terminal Zn1, the C-terminal Zn2, and the central linker. The Zn2 domain, which is dispensable for transcription elongation and TCR functions, is essential for Rpb9 to promote Rpb1 degradation, whereas the Zn1 and linker domains, which are essential for transcription elongation and TCR functions, play a subsidiary role in Rpb1 degradation. Coimmunoprecipitation analysis suggests that almost the full length of Rpb9 is required for a strong interaction with the core Pol II: deletion of the Zn2 domain causes dramatically weakened interaction, whereas deletion of Zn1 and the linker resulted in undetectable interaction. Furthermore, we show that Rpb1, rather than the whole Pol II complex, is degraded in response to UV radiation and that the degradation is primarily mediated by the 26S proteasome.
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Affiliation(s)
- Xuefeng Chen
- Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
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8
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Smutok OV, Os’mak GS, Gaida GZ, Gonchar MV. Screening of yeasts producing stable L-lactate cytochrome c oxidoreductase and study of the regulation of enzyme synthesis. Microbiology (Reading) 2006. [DOI: 10.1134/s0026261706010048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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9
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Large-scale Phenotypic Analysis in Microtitre Plates of Mutants with Deleted Open Reading Frames from Yeast Chromosome III: Key-step Between Genomic Sequencing and Protein Function. J Microbiol Methods 1999. [DOI: 10.1016/s0580-9517(08)70206-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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10
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Park JI, Grant CM, Attfield PV, Dawes IW. The freeze-thaw stress response of the yeast Saccharomyces cerevisiae is growth phase specific and is controlled by nutritional state via the RAS-cyclic AMP signal transduction pathway. Appl Environ Microbiol 1997; 63:3818-24. [PMID: 9327544 PMCID: PMC168690 DOI: 10.1128/aem.63.10.3818-3824.1997] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The ability of cells to survive freezing and thawing is expected to depend on the physiological conditions experienced prior to freezing. We examined factors affecting yeast cell survival during freeze-thaw stress, including those associated with growth phase, requirement for mitochondrial functions, and prior stress treatment(s), and the role played by relevant signal transduction pathways. The yeast Saccharomyces cerevisiae was frozen at -20 degrees C for 2 h (cooling rate, less than 4 degrees C min-1) and thawed on ice for 40 min. Supercooling occurred without reducing cell survival and was followed by freezing. Loss of viability was proportional to the freezing duration, indicating that freezing is the main determinant of freeze-thaw damage. Regardless of the carbon source used, the wild-type strain and an isogenic petite mutant ([rho 0]) showed the same pattern of freeze-thaw tolerance throughout growth, i.e., high resistance during lag phase and low resistance during log phase, indicating that the response to freeze-thaw stress is growth phase specific and not controlled by glucose repression. In addition, respiratory ability and functional mitochondria are necessary to confer full resistance to freeze-thaw stress. Both nitrogen and carbon source starvation led to freeze-thaw tolerance. The use of strains affected in the RAS-cyclic AMP (RAS-cAMP) pathway or supplementation of an rca1 mutant (defective in the cAMP phosphodiesterase gene) with cAMP showed that the freeze-thaw response of yeast is under the control of the RAS-cAMP pathway. Yeast did not adapt to freeze-thaw stress following repeated freeze-thaw treatment with or without a recovery period between freeze-thaw cycles, nor could it adapt following pretreatment by cold shock. However, freeze-thaw tolerance of yeast cells was induced during fermentative and respiratory growth by pretreatment with H2O2, cycloheximide, mild heat shock, or NaCl, indicating that cross protection between freeze-thaw stress and a limited number of other types of stress exists.
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Affiliation(s)
- J I Park
- School of Biochemistry and Molecular Genetics, University of New South Wales, Sydney, Australia
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11
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Genetic regulation of the qa gene cluster of Neurospora crassa: induction of qa messenger ribonucleic acid and dependency on qa-1 function. Mol Cell Biol 1997. [PMID: 9279395 DOI: 10.1128/mcb.1.9.829] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An in vitro protein-synthesizing system (rabbit reticulocyte) was programmed with total polyadenylated messenger ribonucleic acid from wild type and various mutants in the qa gene cluster of Neurospora crassa. The products of two of the qa genes, quinate dehydrogenase (qa-3+) and dehydroshikimate dehydratase (qa-4+), were identified by specific immunoprecipitation and sodium dodecyl sulfate-slab gel electrophoresis. The results indicated that for both genes induction of a specific enzyme activity by quinic acid depends on the de novo synthesis of a specific polypeptide and on the de novo appearance of specific messenger ribonucleic acid detectable by the in vitro translation assay. Furthermore, the results indicated that the appearance of this messenger ribonucleic acid is under the control of the qa-1 gene. The simplest interpretation of these results appears to be that induction of enzyme activity in the qa system is mediated by events at the transcriptional level.
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12
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François J, Neves MJ, Hers HG. The control of trehalose biosynthesis in Saccharomyces cerevisiae: evidence for a catabolite inactivation and repression of trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase. Yeast 1991; 7:575-87. [PMID: 1662849 DOI: 10.1002/yea.320070605] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
During diauxic growth of yeast in glucose-rich medium, the accumulation of trehalose started well after complete exhaustion of glucose from the medium. The accumulation of the disaccharide was concomitant with a resumption of cell growth on the ethanol accumulated in the medium, but not with a degradation of glycogen which occurred as soon as glucose had been consumed. In contrast, in a mutant deficient in phosphoenolpyruvate carboxykinase, the synthesis of trehalose coincided exactly with the degradation of glycogen. Upon inoculation of stationary phase wild-type cells into a glucose medium, the activities of trehalose-6-phosphate (Tre6P) synthase and Tre6P phosphatase dropped in parallel to reach only 15% of their initial values after 3 h, and only recovered their original values as cells re-entered stationary phase. In the presence of cycloheximide, the decrease in Tre6P synthase and Tre6P phosphatase activities was restricted to 50-60%, the remaining decrease being inhibited by the drug. Furthermore, the reappearance of the enzyme activities following transfer of cells to an acetate medium was blocked by cycloheximide. It was also shown that loss of activity of these two enzymes required a combination of metabolizable sugars together with a nitrogen source. Low activities of Tre6P synthase and Tre6P phosphatase were measured in mutants with increased adenylate cyclase activity (RAS2ala18val19 mutants). Moreover, derepression of these enzymes at the approach of stationary phase was prevented in a pde2 mutant when it was cultivated in the presence of exogenous cyclic nucleotide. The mechanism of this effect is not clear, but may involve a transcriptional regulation by cAMP of the genes encoding these proteins.
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Affiliation(s)
- J François
- Laboratoire de Chimie Physiologique Université Catholique de Louvain, Belgium
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14
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Sosinsky G, Schekman R, Glaeser RM. Morphological observations on the formation and stability of the crystalline arrays in the plasma membrane of Saccharomyces cerevisiae. JOURNAL OF ULTRASTRUCTURE AND MOLECULAR STRUCTURE RESEARCH 1986; 94:37-51. [PMID: 3534113 DOI: 10.1016/0889-1605(86)90050-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Two-dimensional crystalline arrays of freeze-fracture particles are known to occur in abundant quantities in the plasma membrane of stationary state yeast cells. Although these crystalline arrays are seen only infrequently in cells during mid-exponential growth, we now observe that formation of crystalline arrays can be induced in such cells by a "metabolic starvation" protocol. Surprisingly, starvation-induced formation of crystalline patches can be prevented by inhibition of new protein synthesis during the starvation period. The size and quantity of crystalline arrays can be increased by removal of the cell wall prior to starvation. Induction of crystalline arrays in protoplasts has made it possible to investigate the surface morphology of the crystalline particles in isolated membranes as well as at the extracellular surface of intact protoplasts. The stability of isolated crystalline arrays to several detergents has been investigated and conditions have been found that result in improved morphological purity of the isolated crystalline patches.
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15
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Betancourt S, Torres-Bauzá LJ, Rodríguez-Del Valle N. Molecular and cellular events during the yeast to mycelium transition in Sporothrix schenckii. SABOURAUDIA 1985; 23:207-18. [PMID: 4023887 DOI: 10.1080/00362178585380311] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Unbudded singlets from exponentially growing yeast cells of Sporothrix schenckii were harvested, selected by filtration and allowed to form germ tubes in a basal medium with glucose at pH 4.0 and 25 degrees C. These conditions supported only the development of the mycelial form of S. schenckii in a reproducible manner which allowed further analysis of the early cellular events occurring during the yeast-to-mycelium transition. The relationship between macromolecular synthesis (DNA and RNA synthesis) and nuclear division, hyphal growth and septum formation were investigated during germ tube formation. RNA synthesis started 0 to 3 h after the induction of germ tube formation, followed by DNA synthesis and the first nuclear division, which took place between 3 and 6 h. Germ tube formation followed nuclear division and was first evidenced 6 h after the induction of germ tube formation, but was not completed until 12 h after inoculation. Septation was first observed in these germ tubes at the mother cell-germ tube junction 6 h after induction. Addition of hydroxyurea, an inhibitor of DNA synthesis, to the medium, also inhibited nuclear division and germ tube growth, suggesting that these processes in S. schenckii are dependent upon DNA synthesis.
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16
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Abstract
We have analyzed the cell cycle kinetics of Aspergillus nidulans by using the DNA synthesis inhibitor hydroxyurea (HU) and a temperature-sensitive cell cycle mutant nimT that blocks in G2. HU rapidly inhibits DNA synthesis (S), and as a consequence progression beyond S to mitosis (M) is blocked. Upon removal of HU the inhibition is rapidly reversible. Conidia (asexual spores) of nimT were germinated at restrictive temperature to synchronize germlings in G2 and then downshifted to permissive temperature in the presence of HU. This procedure synchronizes the germlings at the beginning of S in the second cell cycle after spore germination. We have measured the total duration of S, G2, and M as the time required for these cells to recover from the HU block and undergo the next nuclear division. The duration of S was defined by the time course of sensitivity to reintroduction of HU during recovery from the initial HU block. The cell cycle time was measured as the nuclear doubling time, and the duration of mitosis was determined from the mitotic index. The duration of G1 was calculated by subtracting the combined durations of S, G2, and M from the nuclear doubling time, and the length of G2 was calculated by subtracting S and M from the aggregate length of S, G2, and M. We have also determined the duration of the phases of the cell cycle during the first cycle after spore germination. In these experiments spores were germinated directly in HU without first being blocked in G2. Because the durations of G1, S, G2, and M for the first cell cycle after spore germination were identical with those previously determined for spores presynchronized at the beginning of S in the second cell cycle, we conclude that dormant conidia of A. nidulans are arrested at, or before, the start of S.
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17
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Reinert WR, Patel VB, Giles NH. Genetic regulation of the qa gene cluster of Neurospora crassa: induction of qa messenger ribonucleic acid and dependency on qa-1 function. Mol Cell Biol 1981; 1:829-35. [PMID: 9279395 PMCID: PMC369366 DOI: 10.1128/mcb.1.9.829-835.1981] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
An in vitro protein-synthesizing system (rabbit reticulocyte) was programmed with total polyadenylated messenger ribonucleic acid from wild type and various mutants in the qa gene cluster of Neurospora crassa. The products of two of the qa genes, quinate dehydrogenase (qa-3+) and dehydroshikimate dehydratase (qa-4+), were identified by specific immunoprecipitation and sodium dodecyl sulfate-slab gel electrophoresis. The results indicated that for both genes induction of a specific enzyme activity by quinic acid depends on the de novo synthesis of a specific polypeptide and on the de novo appearance of specific messenger ribonucleic acid detectable by the in vitro translation assay. Furthermore, the results indicated that the appearance of this messenger ribonucleic acid is under the control of the qa-1 gene. The simplest interpretation of these results appears to be that induction of enzyme activity in the qa system is mediated by events at the transcriptional level.
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Affiliation(s)
- W R Reinert
- Department of Molecular and Population Genetics, University of Georgia, Athens 30602, USA
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18
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Inderlied CB, Cihlar RL, Sypherd PS. Regulation of ornithine decarboxylase during morphogenesis of Mucor racemosus. J Bacteriol 1980; 141:699-706. [PMID: 6245054 PMCID: PMC293678 DOI: 10.1128/jb.141.2.699-706.1980] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
During the yeast-to-hyphae transition of the dimorphic phycomycete Mucor racemosus, there was a 30- to 50-fold increase in the activity of ornithine decarboxylase. Increased enzyme activity preceded the emergence of germ tubes and reached a maximum before conversion was completed. Subsequently, enzyme levels rapidly declined, despite the continuation of mycelial growth. Both putrescine and spermidine blocked the enzyme activity response. Protein synthesis was required for the increase in enzyme activity during morphogenesis. A combination of actinomycin D and netropsin inhibited ribonucleic acid synthesis but failed to inhibit the increase in ornithine decarboxylase activity. There was a twofold increase in the enzyme half-life during morphogenesis with either trichodermin or verrucarin to inhibit protein synthesis.
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19
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Gorenstein C, Atkinson KD, Falkes EV. Isolation and characterization of an actinomycin D-sensitive mutant of Saccharomyces cerevisiae. J Bacteriol 1978; 136:142-7. [PMID: 361685 PMCID: PMC218643 DOI: 10.1128/jb.136.1.142-147.1978] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
A single mutation in Saccharomyces cerevisiae conferred sensitivity to low concentrations of actinomycin D. Treatment with actinomycin D preferentially inhibited synthesis of rRNA's. Residual rRNA synthesized was processed normally. Total protein synthesis and inducibility of the enzyme maltase were relatively unaffected at concentrations of actinomycin D which severely inhibited rRNA synthesis.
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Gupta RS, Siminovitch L. Mutants of CHO cells resistant to the protein synthesis inhibitors, cryptopleurine and tylocrebrine: genetic and biochemical evidence for common site of action of emetine, cryptopleurine, tylocrebine, and tubulosine. Biochemistry 1977; 16:3209-14. [PMID: 560858 DOI: 10.1021/bi00633a026] [Citation(s) in RCA: 75] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Stable mutants resistant to the protein synthesis inhibitors cryptopleurine and tylocrebine can be isolated in Chinese hamster ovary (CHO) cells, in a single step. The frequency of occurrence of cryptopleurine (CryR) and tylocrebrine (TylR) resistant mutants in normal and mutagenized cell populations is similar to that observed for emetine resistant (EmtR) mutants. The CryR, TylR, and EmtR mutants exhibit strikingly similar cross-resistance to the three drugs used for selection, to tubulosine and also to two emetine derivatives cephaeline and dehydroemetine, based on assays of in vivo cytotoxicity and on assays of protein synthesis in cell-free extracts. The identity of cross-resistance patterns of the CryR, TylR, and EmtR mutants indicates that the resistance to all these compounds results from the same primary lesion, which in the case of EmtR cells has been shown to affect the 40S ribosomal subunit. This conclusion is strongly supported by the failure of EmtR, TylR, and CryR mutants to complement each other in somatic cell hybrids. Based on these results it is suggested that the above group of compounds possesses common structural determinants which are responsible for their activity. The above mutants, however, do not show any cross-resistance to other inhibitors of protein synthesis such as cycloheximide, trichodermin, anisomycin, pactamycin, and sparsomycin, either in vivo or in vitro, indicating that the site of action of these inhibitors is different from that of the emetine-like compounds.
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Bandlow W, Metzke R, Klein A, Kotzias K, Doxiadis I, Bechmann H, Schweyen RJ, Kaudewitz F. Macromolecular synthesis and energy level in a mitochondrial conditional yeast mutant, tsm-8. EUROPEAN JOURNAL OF BIOCHEMISTRY 1977; 76:373-82. [PMID: 330160 DOI: 10.1111/j.1432-1033.1977.tb11605.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Mitochondrial DNA, protein and ATP syntheses persist at non-permissive temperature (35 degrees C) in the mitochondrial, conditionally rho- petites forming yeast mutant, tsm8. Protein and ATP syntheses, however, are diminished during prolonged incubation at 35 degrees C in non-fermentable substrate. Mitochondrial RNA synthesis decreases rapidly to a residual constant level of about 10% of the initial value after the shift to 35 degrees C. The decrease is reversed by returning to permissive conditions. Evidence is presented that this temperature-induced decrease in mitochondrial transcription rate is effected by a mutationally altered regulatory process rather than by temperature sensitivity of mitochondrial RNA polymerase. It is concluded that rho- petite formation in mutant tsm8 is not effected by complete inhibition of macromolecular and ATP syntheses but is correlated with a reduction in mitochondrial transcription.
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Selective inhibition of protein synthesis initiation in Saccharomyces cerevisiae by low concentrations of cycloheximide. J Biol Chem 1976. [DOI: 10.1016/s0021-9258(17)32970-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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