The yeast Mig1 transcriptional repressor is dephosphorylated by glucose-dependent and independent mechanisms

Tyrosine Phosphorylation ◽

Growth Medium ◽

Carbon Sources ◽

Transcriptional Repressor ◽

Altered Glucose ◽

Complex Manner ◽

Dependent Mechanism

AbstractSaccharomyces cerevisiae AMPK/Snf1 regulates glucose derepression of genes required for utilization of alternative carbon sources through the transcriptional repressor Mig1. It has been suggested that the Glc7-Reg1 phosphatase dephosphorylates Mig1. Here we report that Mig1 is dephosphorylated by Glc7-Reg1 in an apparently glucose-dependent mechanism but also by a mechanism independent of glucose and Glc7-Reg1. In addition to serine/threonine phosphatases another process including tyrosine phosphorylation seems crucial for Mig1 regulation. Taken together, Mig1 dephosphorylation appears to be controlled in a complex manner, in line with the importance for rapid and sensitive regulation upon altered glucose concentrations in the growth medium.

Regulation of phosphoenolpyruvate carboxykinase and pyruvate kinase in Saccharomyces cerevisiae grown in the presence of glycolytic and gluconeogenic carbon sources and the role of mitochondrial function on gluconeogenesis

Canadian Journal of Microbiology ◽

10.1139/m86-180 ◽

1986 ◽

Vol 32 (12) ◽

pp. 969-972 ◽

Cited By ~ 7

Author(s):

Albert J. Wilson ◽

J. K. Bhattacharjee

Keyword(s):

Pyruvate Kinase ◽

Growth Medium ◽

Phosphoenolpyruvate Carboxykinase ◽

Carbon Sources ◽

Absolute Requirement ◽

Fructose 1,6 Bisphosphatase ◽

Futile Cycling ◽

Respiratory Deficient

Phosphoenolpyruvate carboxykinase (PEPCKase) and pyruvate kinase (PKase) were measured in Saccharomyces cerevisiae grown in the presence of glycolytic and gluconeogenic carbon sources. The PEPCKase activity was highest in ethanol-grown cells. However, high PEPCKase activity was also observed in cells grown in 1% glucose, especially as compared with the activity of sucrose-, maltose-, or galactose-grown cells. Activity was first detected after 12 h when glucose was exhausted from the growth medium. The PKase activity was very high in glucose-grown cells; considerable activity was also present in ethanol- and pyruvate-grown cells. The absolute requirement of respiration for gluconeogenesis was demonstrated by the absence or significantly low levels of PEPCKase and fructose-1,6-bisphosphatase activities observed in respiratory deficient mutants, as well as in wild-type S. cerevisiae cells grown in the presence of glucose and antimycin A or chloramphenicol. Obligate glycolytic and gluconeogenic enzymes were present sumultaneously only in stationary phase cells, but not in exponential phase cells; hence futile cycling could not occur in log phase cells regardless of the presence of carbon source in the growth medium.

Mig1 localization exhibits biphasic behavior which is controlled by both metabolic and regulatory roles of the sugar kinases

Molecular Genetics and Genomics ◽

10.1007/s00438-020-01715-4 ◽

2020 ◽

Vol 295 (6) ◽

pp. 1489-1500

Author(s):

Gregor W. Schmidt ◽

Niek Welkenhuysen ◽

Tian Ye ◽

Marija Cvijovic ◽

Stefan Hohmann

Keyword(s):

Nuclear Localization ◽

Essential Role ◽

Carbon Sources ◽

Transcriptional Repressor ◽

Energy Sources ◽

Nucleocytoplasmic Shuttling

Abstract Glucose, fructose and mannose are the preferred carbon/energy sources for the yeast Saccharomyces cerevisiae. Absence of preferred energy sources activates glucose derepression, which is regulated by the kinase Snf1. Snf1 phosphorylates the transcriptional repressor Mig1, which results in its exit from the nucleus and subsequent derepression of genes. In contrast, Snf1 is inactive when preferred carbon sources are available, which leads to dephosphorylation of Mig1 and its translocation to the nucleus where Mig1 acts as a transcription repressor. Here we revisit the role of the three hexose kinases, Hxk1, Hxk2 and Glk1, in glucose de/repression. We demonstrate that all three sugar kinases initially affect Mig1 nuclear localization upon addition of glucose, fructose and mannose. This initial import of Mig1 into the nucleus was temporary; for continuous nucleocytoplasmic shuttling of Mig1, Hxk2 is required in the presence of glucose and mannose and in the presence of fructose Hxk2 or Hxk1 is required. Our data suggest that Mig1 import following exposure to preferred energy sources is controlled via two different pathways, where (1) the initial import is regulated by signals derived from metabolism and (2) continuous shuttling is regulated by the Hxk2 and Hxk1 proteins. Mig1 nucleocytoplasmic shuttling appears to be important for the maintenance of the repressed state in which Hxk1/2 seems to play an essential role.

Properties of particulate and solubilized phosphatidylserine synthase activity from Saccharomyces cerevisiae. Inhibitory effect of choline in the growth medium.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)34304-7 ◽

1982 ◽

Vol 257 (14) ◽

pp. 8115-8121 ◽

Cited By ~ 7

Author(s):

M A Carson ◽

K D Atkinson ◽

C J Waechter

Keyword(s):

Growth Medium ◽

Inhibitory Effect ◽

Phosphatidylserine Synthase

Underproduction of the Largest Subunit of RNA Polymerase II Causes Temperature Sensitivity, Slow Growth, and Inositol Auxotrophy in Saccharomyces cerevisiae

Genetics ◽

10.1093/genetics/142.3.737 ◽

1996 ◽

Vol 142 (3) ◽

pp. 737-747 ◽

Cited By ~ 7

Author(s):

Jacques Archambault ◽

David B Jansma ◽

James D Friesen

Keyword(s):

Steady State ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Reporter Gene ◽

Growth Medium ◽

Temperature Sensitivity ◽

Slow Growth ◽

Genes Encoding

Abstract In the yeast Saccharomyces cerevisiae, mutations in genes encoding subunits of RNA polymerase II (RNAPII) often give rise to a set of pleiotropic phenotypes that includes temperature sensitivity, slow growth and inositol auxotrophy. In this study, we show that these phenotypes can be brought about by a reduction in the intracellular concentration of RNAPII. Underproduction of RNAPII was achieved by expressing the gene (RPO21), encoding the largest subunit of the enzyme, from the LEU2 promoter or a weaker derivative of it, two promoters that can be repressed by the addition of leucine to the growth medium. We found that cells that underproduced RPO21 were unable to derepress fully the expression of a reporter gene under the control of the INO1 UAS. Our results indicate that temperature sensitivity, slow growth and inositol auxotrophy is a set of phenotypes that can be caused by lowering the steady-state amount of RNAPII; these results also lead to the prediction that some of the previously identified RNAPII mutations that confer this same set of phenotypes affect the assembly/stability of the enzyme. We propose a model to explain the hypersensitivity of INO1 transcription to mutations that affect components of the RNAPII transcriptional machinery.

Multicopy FZF1 (SUL1) Suppresses the Sulfite Sensitivity but Not the Glucose Derepression or Aberrant Cell Morphology of a grr1 Mutant of Saccharomyces cerevisiae

Genetics ◽

10.1093/genetics/144.2.511 ◽

1996 ◽

Vol 144 (2) ◽

pp. 511-521 ◽

Cited By ~ 3

Author(s):

Dorina Avram ◽

Alan T Bakalinsky

Keyword(s):

Transcription Factor ◽

Glucose Metabolism ◽

Cell Morphology ◽

Glucose Repression ◽

Carbon Sources ◽

Single Copy ◽

Aberrant Cell ◽

Growth Defects ◽

Putative Transcription Factor

Abstract An ssu2 mutation in Sacccharomyces cermisiae, previously shown to cause sulfite sensitivity, was found to be allelic to GRR1, a gene previously implicated in glucose repression. The suppressor rgt1, which suppresses the growth defects of grr1 strains on glucose, did not fully suppress the sensitivity on glucose or nonglucose carbon sources, indicating that it is not strictly linked to a defect in glucose metabolism. Because the Cln1 protein was previously shown to be elevated in grr1 mutants, the effect of CLN1 overexpression on sulfite sensitivity was investigated. Overexpression in GRR1 cells resulted in sulfite sensitivity, suggesting a connection between CLN1 and sulfite metabolism. Multicopy FZF1, a putative transcription factor, was found to suppress the sulfite sensitive phenotype of grr1 strains, but not the glucose derepression or aberrant cell morphology. Multicopy FZF1 was also found to suppress the sensitivity of a number of other unrelated sulfite-sensitive mutants, but not that of ssu1 or met20, implying that FZF1 may act through Ssulp and Met20p. Disruption of FZF1 resulted in sulfite sensitivity when the construct was introduced in single copy at the FZF1 locus in a GRR1 strain, providing evidence that FZF1 is involved in sulfite metabolism.

Maintenance of Mitochondrial Morphology Is Linked to Maintenance of the Mitochondrial Genome in Saccharomyces cerevisiae

Genetics ◽

10.1093/genetics/162.3.1147 ◽

2002 ◽

Vol 162 (3) ◽

pp. 1147-1156 ◽

Cited By ~ 1

Author(s):

Theodor Hanekamp ◽

Mary K Thorsness ◽

Indrani Rebbapragada ◽

Elizabeth M Fisher ◽

Corrine Seebart ◽

...

Keyword(s):

Growth Rate ◽

Mitochondrial Dna ◽

Carbon Sources ◽

Mitochondrial Morphology ◽

Slow Growth Rate ◽

Dna Migration ◽

Mitochondrial Dna Stability ◽

Extragenic Suppressors

Abstract In the yeast Saccharomyces cerevisiae, certain mutant alleles of YME4, YME6, and MDM10 cause an increased rate of mitochondrial DNA migration to the nucleus, carbon-source-dependent alterations in mitochondrial morphology, and increased rates of mitochondrial DNA loss. While single mutants grow on media requiring mitochondrial respiration, any pairwise combination of these mutations causes a respiratory-deficient phenotype. This double-mutant phenotype allowed cloning of YME6, which is identical to MMM1 and encodes an outer mitochondrial membrane protein essential for maintaining normal mitochondrial morphology. Yeast strains bearing null mutations of MMM1 have altered mitochondrial morphology and a slow growth rate on all carbon sources and quantitatively lack mitochondrial DNA. Extragenic suppressors of MMM1 deletion mutants partially restore mitochondrial morphology to the wild-type state and have a corresponding increase in growth rate and mitochondrial DNA stability. A dominant suppressor also suppresses the phenotypes caused by a point mutation in MMM1, as well as by specific mutations in YME4 and MDM10.

The Cloning and Mapping of ADR6, a Gene Required for Sporulation and for Expression of the Alcohol Dehydrogenase II Isozyme From Saccharomyces cerevisiae

Genetics ◽

10.1093/genetics/116.4.531 ◽

1987 ◽

Vol 116 (4) ◽

pp. 531-540

Author(s):

Aileen K W Taguchi ◽

Elton T Young

Keyword(s):

Alcohol Dehydrogenase ◽

Single Gene ◽

Carbon Sources ◽

Transcription Unit ◽

Yeast Cells ◽

Recessive Mutation ◽

Upstream Activating Sequence ◽

A Site

ABSTRACT The alcohol dehydrogenase II (ADH2) gene of the yeast, Saccharomyces cerevisiae, is not transcribed during growth on fermentable carbon sources such as glucose. Growth of yeast cells in a medium containing only nonfermentable carbon sources leads to a marked increase or derepression of ADH2 expression. The recessive mutation, adr6-1, leads to an inability to fully derepress ADH2 expression and to an inability to sporulate. The ADR6 gene product appears to act directly or indirectly on ADH2 sequences 3' to or including the presumptive TATAA box. The upstream activating sequence (UAS) located 5' to the TATAA box is not required for the Adr6- phenotype. Here, we describe the isolation of a recombinant plasmid containing the wild-type ADR6 gene. ADR6 codes for a 4.4-kb RNA which is present during growth both on glucose and on nonfermentable carbon sources. Disruption of the ADR6 transcription unit led to viable cells with decreased ADHII activity and an inability to sporulate. This indicates that both phenotypes result from mutations within a single gene and that the adr6-1 allele was representative of mutations at this locus. The ADR6 gene mapped to the left arm of chromosome XVI at a site 18 centimorgans from the centromere.

Cloning and genetic mapping of SNF1, a gene required for expression of glucose-repressible genes in Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.4.1.49-53.1984 ◽

1984 ◽

Vol 4 (1) ◽

pp. 49-53

Author(s):

J L Celenza ◽

M Carlson

Keyword(s):

Genetic Mapping ◽

Gene Product ◽

Structural Gene ◽

Glucose Repression ◽

Carbon Sources ◽

Recombinant Plasmids ◽

The Right ◽

Integrating Vector

A functional SNF1 gene product is required to derepress expression of many glucose-repressible genes in Saccharomyces cerevisiae. Strains carrying a snf1 mutation are unable to grow on sucrose, galactose, maltose, melibiose, or nonfermentable carbon sources; utilization of these carbon sources is regulated by glucose repression. The inability of snf1 mutants to utilize sucrose results from failure to derepress expression of the structural gene for invertase at the RNA level. We isolated recombinant plasmids carrying the SNF1 gene by complementation of the snf1 defect in S. cerevisiae. A 3.5-kilobase region is common to the DNA segments cloned in five different plasmids. Transformation of S. cerevisiae with an integrating vector carrying a segment of the cloned DNA resulted in integration of the plasmid at the SNF1 locus. This result indicates that the cloned DNA is homologous to sequences at the SNF1 locus. By mapping a plasmid marker linked to SNF1 in this transformant, we showed that the SNF1 gene is located on chromosome IV. We then mapped snf1 to a position 5.6 centimorgans distal to rna3 on the right arm; snf1 is not extremely closely linked to any previously mapped mutation.

The Identification and Characterization of ADR6, a Gene Required for Sporulation and for Expression of the Alcohol Dehydrogenase II Isozyme From Saccharomyces cerevisiae

Genetics ◽

10.1093/genetics/116.4.523 ◽

1987 ◽

Vol 116 (4) ◽

pp. 523-530

Author(s):

Aileen K W Taguchi ◽

Elton T Young

Keyword(s):

Alcohol Dehydrogenase ◽

Isocitrate Lyase ◽

Carbon Sources ◽

Recessive Mutation ◽

Identification And Characterization

Upstream Activating Sequence ◽

Adh Activity ◽

ABSTRACT The alcohol dehydrogenase II isozyme (enzyme, ADHII; structural gene, ADH2) of the yeast, Saccharomyces cerevisiae, is under stringent carbon catabolite control. This cytoplasmic isozyme exhibits negligible activity during growth in media containing fermentable carbon sources such as glucose and is maximal during growth on nonfermentable carbon sources. A recessive mutation, adr6-1, and possibly two other alleles at this locus, were selected for their ability to decrease Ty-activated ADH2-6 c expression. The adr6-1 mutation led to decreased ADHII activity in both ADH2-6c and ADH2+ strains, and to decreased levels of ADH2 mRNA. Ty transcription and the expression of two other carbon catabolite regulated enzymes, isocitrate lyase and malate dehydrogenase, were unaffected by the adr6-1 mutation. adr6-1/adr6-1strains were defective for sporulation, indicating that adr6 mutations may have pleiotropic effects. The sporulation defect was not a consequence of decreased ADH activity. Since the ADH2-6c mutation is due to insertion of a 5.6-kb Ty element at the TATAA box, it appears that the ADR6+-dependent ADHII activity required ADH2 sequences 3′ to or including the TATAA box. The ADH2 upstream activating sequence (UAS) was probably not required. The ADR6 locus was unlinked to the ADR1 gene which encodes another trans-acting element required for ADH2 expression.

Screening and directed evolution of transporters to improve xylodextrin utilization in the yeast Saccharomyces cerevisiae

10.1101/166678 ◽

2017 ◽

Author(s):

Chenlu Zhang ◽

Ligia Acosta-Sampson ◽

Vivian Yaci Yu ◽

Jamie H. D. Cate

Keyword(s):

Directed Evolution ◽

Plant Biomass ◽

Carbon Sources ◽

Industrial Applications ◽

Cellulosic Biofuel ◽

Economic Production ◽

Report Analysis ◽

Selection Medium

AbstractThe economic production of cellulosic biofuel requires efficient and full utilization of all abundant carbohydrates naturally released from plant biomass by enzyme cocktails. Recently, we reconstituted the Neurospora crassa xylodextrin transport and consumption system in Saccharomyces cerevisiae, enabling growth of yeast on xylodextrins aerobically. However, the consumption rate of xylodextrin requires improvement for industrial applications, including consumption in anaerobic conditions. As a first step in this improvement, we report analysis of orthologues of the N. crassa transporters CDT-1 and CDT-2. Transporter ST16 from Trichoderma virens enables faster aerobic growth of S. cerevisiae on xylodextrins compared to CDT-2. ST16 is a xylodextrin-specific transporter, and the xylobiose transport activity of ST16 is not inhibited by cellobiose. Other transporters identified in the screen also enable growth on xylodextrins including xylotriose. Taken together, these results indicate that multiple transporters might prove useful to improve xylodextrin utilization in S. cerevisiae. Efforts to use directed evolution to improve ST16 from a chromosomally-integrated copy were not successful, due to background growth of yeast on other carbon sources present in the selection medium. Future experiments will require increasing the baseline growth rate of the yeast population on xylodextrins, to ensure that the selective pressure exerted on xylodextrin transport can lead to isolation of improved xylodextrin transporters.