Regulation of glutamine-repressible gene products by the GLN3 function in Saccharomyces cerevisiae

1984 ◽  
Vol 4 (12) ◽  
pp. 2758-2766
Author(s):  
A P Mitchell ◽  
B Magasanik
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Glutamine Synthetase ◽  
Glutamate Dehydrogenase ◽  
Opposite Effect ◽  
Nuclear Gene ◽  
Yeast Saccharomyces Cerevisiae ◽  
Two Dimensional Gel Electrophoresis ◽  
Regulatory Circuit ◽  
Glutamate Dehydrogenase Activity ◽  
Glutamine Limitation

Mutants of the yeast Saccharomyces cerevisiae have been isolated which fail to derepress glutamine synthetase upon glutamine limitation. The mutations define a single nuclear gene, GLN3, which is located on chromosome 5 near HOM3 and HIS1 and is unlinked to the structural gene for glutamine synthetase, GLN1. The three gln3 mutations are recessive, and one is amber suppressible, indicating that the GLN3 product is a positive regulator of glutamine synthetase expression. Four polypeptides, in addition to the glutamine synthetase subunit are synthesized at elevated rates when GLN3+ cultures are shifted from glutamine to glutamate media as determined by pulse-labeling and one- and two-dimensional gel electrophoresis. The response of all four proteins is blocked by gln3 mutations. In addition, the elevated NAD-dependent glutamate dehydrogenase activity normally found in glutamate-grown cells is not found in gln3 mutants. Glutamine limitation of gln1 structural mutants has the opposite effect, causing elevated levels of NAD-dependent glutamate dehydrogenase even in the presence of ammonia. We suggest that there is a regulatory circuit that responds to glutamine availability through the GLN3 product.

scholarly journals Regulation of glutamine-repressible gene products by the GLN3 function in Saccharomyces cerevisiae.

1984 ◽  
Vol 4 (12) ◽  
pp. 2758-2766 ◽  
Author(s):  
A P Mitchell ◽  
B Magasanik
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Glutamine Synthetase ◽  
Glutamate Dehydrogenase ◽  
Opposite Effect ◽  
Nuclear Gene ◽  
Yeast Saccharomyces Cerevisiae ◽  
Two Dimensional Gel Electrophoresis ◽  
Regulatory Circuit ◽  
Glutamate Dehydrogenase Activity ◽  
Glutamine Limitation

Mutants of the yeast Saccharomyces cerevisiae have been isolated which fail to derepress glutamine synthetase upon glutamine limitation. The mutations define a single nuclear gene, GLN3, which is located on chromosome 5 near HOM3 and HIS1 and is unlinked to the structural gene for glutamine synthetase, GLN1. The three gln3 mutations are recessive, and one is amber suppressible, indicating that the GLN3 product is a positive regulator of glutamine synthetase expression. Four polypeptides, in addition to the glutamine synthetase subunit are synthesized at elevated rates when GLN3+ cultures are shifted from glutamine to glutamate media as determined by pulse-labeling and one- and two-dimensional gel electrophoresis. The response of all four proteins is blocked by gln3 mutations. In addition, the elevated NAD-dependent glutamate dehydrogenase activity normally found in glutamate-grown cells is not found in gln3 mutants. Glutamine limitation of gln1 structural mutants has the opposite effect, causing elevated levels of NAD-dependent glutamate dehydrogenase even in the presence of ammonia. We suggest that there is a regulatory circuit that responds to glutamine availability through the GLN3 product.

scholarly journals Role of the complex upstream region of the GDH2 gene in nitrogen regulation of the NAD-linked glutamate dehydrogenase in Saccharomyces cerevisiae.

1991 ◽  
Vol 11 (12) ◽  
pp. 6229-6247 ◽  
Author(s):  
S M Miller ◽  
B Magasanik
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Glutamine Synthetase ◽  
Nitrogen Source ◽  
Glutamate Dehydrogenase ◽  
Regulatory System ◽  
Sole Source ◽  
Lacz Fusion ◽  
Upstream Region ◽  
In Cells

We analyzed the upstream region of the GDH2 gene, which encodes the NAD-linked glutamate dehydrogenase in Saccharomyces cerevisiae, for elements important for the regulation of the gene by the nitrogen source. The levels of this enzyme are high in cells grown with glutamate as the sole source of nitrogen and low in cells grown with glutamine or ammonium. We found that this regulation occurs at the level of transcription and that a total of six sites are required to cause a CYC1-lacZ fusion to the GDH2 gene to be regulated in the same manner as the NAD-linked glutamate dehydrogenase. Two sites behaved as upstream activation sites (UASs). The remaining four sites were found to block the effects of the two UASs in such a way that the GDH2-CYC1-lacZ fusion was not expressed unless the cells containing it were grown under conditions favorable for the activity of both UASs. This complex regulatory system appears to account for the fact that GDH2 expression is exquisitely sensitive to glutamine, whereas the expression of GLN1, coding for glutamine synthetase, is not nearly as sensitive.

Isolation and characterization of STI1, a stress-inducible gene from Saccharomyces cerevisiae

1989 ◽  
Vol 9 (9) ◽  
pp. 3638-3646
Author(s):  
C M Nicolet ◽  
E A Craig
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Yeast Saccharomyces Cerevisiae ◽  
Two Dimensional Gel Electrophoresis ◽  
Reading Frame ◽  
Hsp70 Family ◽  
Isolation And Characterization ◽  
Isoelectric Points ◽  
Amino Acid Analog ◽  
Inducible Gene

We have isolated a gene from the yeast Saccharomyces cerevisiae that encodes a 2.0-kilobase heat-inducible mRNA. This gene, which we have designated STI1, for stress inducible, was also induced by the amino acid analog canavanine and showed a slight increase in expression as cells moved into stationary phase. The STI1 gene encodes a 66-kilodalton protein, as determined from the sequence of the longest open reading frame. The putative STI1 protein, as identified by two-dimensional gel electrophoresis, migrated in the region of 73 to 75 kilodaltons as a series of four isoforms with different isoelectric points. STI1 is not homologous to the other conserved HSP70 family members in yeasts, despite similarities in size and regulation. Cells carrying a disruption mutation of the STI1 gene grew normally at 30 degrees C but showed impaired growth at higher and lower temperatures. Overexpression of the STI1 gene resulted in substantial trans-activation of SSA4 promoter-reporter gene fusions, indicating that STI1 may play a role in mediating the heat shock response of some HSP70 genes.

The alpha subunit of initiation factor 2 is phosphorylated in vivo in the yeast Saccharomyces cerevisiae

1986 ◽  
Vol 6 (4) ◽  
pp. 1044-1049
Author(s):  
D P Romero ◽  
A E Dahlberg
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Carbon Sources ◽  
Relative Increase ◽  
Initiation Factor ◽  
Alpha Subunit ◽  
Yeast Saccharomyces Cerevisiae ◽  
Two Dimensional Gel Electrophoresis ◽  
Initiation Factor 2 ◽  
Reticulocyte Lysates

The phosphorylation state of the alpha subunit of initiation factor 2 (eIF-2 alpha) in Saccharomyces cerevisiae has been determined by two-dimensional gel electrophoresis and autoradiography of lysates from cultures grown under a variety of conditions. The alpha subunit was maintained in a phosphorylated state during logarithmic growth on fermentable and nonfermentable carbon sources, during starvation for an essential amino acid, during heat shock, during stationary phase, and during sporulation. Only when cells were starved for a carbon source for 2 h in 1 M sorbitol was eIF-2 alpha isolated in the nonphosphorylated state. This is in contrast with the studies in rabbit reticulocyte lysates, in which arrested protein synthesis was correlated with a relative increase in the extent of phosphorylation of eIF-2 alpha.

Use of lycorine and DAPI staining in Saccharomyces cerevisiae to differentiate between rho0 and rho- cells in a cce1/Δcce1 nuclear background

2000 ◽  
Vol 46 (11) ◽  
pp. 1058-1065 ◽  
Author(s):  
Domenica Rita Massardo ◽  
Stephan G Zweifel ◽  
Norio Gunge ◽  
Isamu Miyakawa ◽  
Nobundo Sando ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Mitochondrial Genome ◽  
Large Fraction ◽  
Nuclear Gene ◽  
Mitochondrial Genomes ◽  
Recognition Sequence ◽  
Dapi Staining ◽  
Yeast Saccharomyces Cerevisiae ◽  
Daughter Cells ◽  
Large Deletions

In the yeast Saccharomyces cerevisiae, mutants are viable with large deletions (rho-), or even complete loss of the mitochondrial genome (rho0). One class of rho- mutants, which is called hypersuppressive, is characterised by a high transmission of the mutated mitochondrial genome to the diploid progeny when mated to a wild-type (rho+) haploid. The nuclear gene CCE1 encodes a cruciform cutting endonuclease, which is located in the mitochondrion and is responsible for the highly biased transmission of the hypersuppressive rho- genome. CCE1 is a Holliday junction specific endonuclease that resolves recombination intermediates in mitochondrial DNA. The cleavage activity shows a strong preference for cutting after a 5'-CT dinucleotide. In the absence of the CCE1 gene product, the mitochondrial genomes remain interconnected and have difficulty segregating to the daughter cells. As a consequence, there is an increase in the fraction of daughter cells that are rho0. In this paper we demonstrate the usefulness of lycorine, together with staining by 4',6-diamidino-2-phenylindole (DAPI), to assay for the mitotic stability of a variety of mitochondrial genomes. We have found that rho+ and rho- strains that contain CT sequences produce a large fraction of rho0 progeny in the absence of CCE1 activity. Only those rho- mitochondrial genomes lacking the CT recognition sequence are unaffected by the cce1 allele.Key words: yeast, mitochondria, hypersuppressive, Saccharomyces cerevisiae, lycorine.

scholarly journals Human Mitochondrial Pathologies of the Respiratory Chain and ATP Synthase: Contributions from Studies of Saccharomyces cerevisiae

Life ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 304
Author(s):  
Leticia V. R. Franco ◽  
Luca Bremner ◽  
Mario H. Barros
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Respiratory Chain ◽  
Atp Synthase ◽  
Molecular Genetic ◽  
Nuclear Gene ◽  
Mitochondrial Diseases ◽  
Basic Knowledge ◽  
Yeast Saccharomyces Cerevisiae ◽  
Catalytic Subunits ◽  
Combined Use

The ease with which the unicellular yeast Saccharomyces cerevisiae can be manipulated genetically and biochemically has established this organism as a good model for the study of human mitochondrial diseases. The combined use of biochemical and molecular genetic tools has been instrumental in elucidating the functions of numerous yeast nuclear gene products with human homologs that affect a large number of metabolic and biological processes, including those housed in mitochondria. These include structural and catalytic subunits of enzymes and protein factors that impinge on the biogenesis of the respiratory chain. This article will review what is currently known about the genetics and clinical phenotypes of mitochondrial diseases of the respiratory chain and ATP synthase, with special emphasis on the contribution of information gained from pet mutants with mutations in nuclear genes that impair mitochondrial respiration. Our intent is to provide the yeast mitochondrial specialist with basic knowledge of human mitochondrial pathologies and the human specialist with information on how genes that directly and indirectly affect respiration were identified and characterized in yeast.

scholarly journals The alpha subunit of initiation factor 2 is phosphorylated in vivo in the yeast Saccharomyces cerevisiae.

1986 ◽  
Vol 6 (4) ◽  
pp. 1044-1049 ◽  
Author(s):  
D P Romero ◽  
A E Dahlberg
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Carbon Sources ◽  
Relative Increase ◽  
Initiation Factor ◽  
Alpha Subunit ◽  
Yeast Saccharomyces Cerevisiae ◽  
Two Dimensional Gel Electrophoresis ◽  
Initiation Factor 2 ◽  
Reticulocyte Lysates

The phosphorylation state of the alpha subunit of initiation factor 2 (eIF-2 alpha) in Saccharomyces cerevisiae has been determined by two-dimensional gel electrophoresis and autoradiography of lysates from cultures grown under a variety of conditions. The alpha subunit was maintained in a phosphorylated state during logarithmic growth on fermentable and nonfermentable carbon sources, during starvation for an essential amino acid, during heat shock, during stationary phase, and during sporulation. Only when cells were starved for a carbon source for 2 h in 1 M sorbitol was eIF-2 alpha isolated in the nonphosphorylated state. This is in contrast with the studies in rabbit reticulocyte lysates, in which arrested protein synthesis was correlated with a relative increase in the extent of phosphorylation of eIF-2 alpha.

Sign in / Sign up

Export Citation Format

Share Document