Iron regulation of triosephosphate isomerase transcript stability in the yeast Saccharomyces cerevisiae

Krieger, K.; Ernst, Joachim F.

doi:10.1099/13500872-140-5-1079

Cited by 10 publications

(8 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition, disruption of TPI1 enhances glycerol production (7) but not glycerol overexpression (S. Rodriguez-Vargas, F. Estruch, and F. RandezGil, unpublished data). It has been also reported previously that iron affects TPI1 expression in S. cerevisiae positively by stabilization of the TPI1 transcript and that this regulation stimulates glycerol production in iron-starved cells (20). Moreover, all the stresses that induce TPI1 have in common a temporary arrest of growth.…”

Section: Discussionmentioning

confidence: 92%

Gene Expression Analysis of Cold and Freeze Stress in Baker's Yeast

Rodríguez-Vargas

Estruch

Rández-Gil

2002

Appl Environ Microbiol

View full text Add to dashboard Cite

We used mRNA differential display to assess yeast gene expression under cold or freeze shock stress conditions. We found both up-and down-regulation of genes, although repression was more common. We identified and sequenced several cold-induced genes exhibiting the largest differences. We confirmed, by Northern blotting, the specificity of the response for TPI1, which encodes triose-phosphate isomerase; ERG10, the gene for acetoacetyl coenzyme A thiolase; and IMH1, which encodes a protein implicated in protein transport. These genes also were induced under other stress conditions, suggesting that this cold response is mediated by a general stress mechanism. We determined the physiological significance of the cold-induced expression change of these genes in two baker's yeast strains with different sensitivities to freeze stress. The mRNA level of TPI1 and ERG10 genes was higher in freeze-stressed than in control samples of the tolerant strain. In contrast, both genes were repressed in frozen cells of the sensitive strain. Next, we examined the effects of ERG10 overexpression on cold and freeze-thaw tolerance. Growth of wild-type cells at 10°C was not affected by high ERG10 expression. However, YEpERG10 transformant cells exhibited increased freezing tolerance. Consistent with this, cells of an erg10 mutant strain showed a clear phenotype of cold and freeze sensitivity. These results give support to the idea that a cause-and-effect relationship between differentially expressed genes and cryoresistance exists in Saccharomyces cerevisiae and open up the possibility of design strategies to improve the freeze tolerance of baker's yeast.Baker's yeast (Saccharomyces cerevisiae) responds to various stresses during its propagation and industrial application (3, 30). For example, extreme environmental conditions arise during freezing, frozen storage, and thawing of bread dough, resulting in yeast cells with reduced viability and dough-leavening capacity (11,14). These effects have a great technological and economic impact because the yeast gassing rate is critical in baking. Consequently, the improvement of the freeze tolerance in baker's yeast is of significant commercial importance.The response of S. cerevisiae to cold shock stress has not been characterized in detail, but it is generally accepted that freeze-thaw tolerance correlates with cellular factors including growth phase (39), respiratory metabolism (22), lipid composition of the membrane (10), and accumulation of trehalose (23,27,37). Cultural conditions that result in yeast cells with these characteristics, especially high trehalose content, are commonly employed in the production of baker's yeast (3, 30), even though they provide stress resistance only in the absence of fermentable sugars (37). Thus, an additional mechanism(s) is thought to be triggered in response to sharp downshift changes in temperature and to be required for the maintenance of freeze tolerance.Regulatory systems that control the stress response in S. cerevisiae act primarily at the transcr...

show abstract

Section: Discussionmentioning

confidence: 92%

Gene Expression Analysis of Cold and Freeze Stress in Baker's Yeast

Rodríguez-Vargas

Estruch

Rández-Gil

2002

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…Because ferrous ions were reported to stabilize the triose-phosphate isomeraze (Tpi) transcripts [22], the Tpi levels in transformants and wild-type strain were assessed by Western blot analysis. Results showed that a significantly lower amount of the enzyme was present in the sf PFKM strain than in the n PFKM and wild-type strains.…”

Section: Resultsmentioning

confidence: 99%

“…The addition of ferrous ions to the medium in the form of FeSO 4 resulted in a significant increase in the growth rate coefficient of the sf PFKM transformant but not that of the n PFKM strain. The stability of the triose-phosphate isomerase ( TPI1 ) transcripts has been reported to be iron-regulated in S. cerevisiae [22] and to be present at levels at least three times higher in iron-supplemented media. Ferrous ions added at 10 μM to the medium led to a higher level of Tpi, especially in sf PFKM cells, in which a significantly lower amount of Tpi was detected with immunoblotting compared with the n PFKM and wild-type strains (Additional file 5: Figure S5).…”

Section: Discussionmentioning

confidence: 99%

Effect of the cancer specific shorter form of human 6-phosphofructo-1-kinase on the metabolism of the yeast Saccharomyces cerevisiae

2017

View full text Add to dashboard Cite

BackgroundAt first glance, there appears to be a high degree of similarity between the metabolism of yeast (the Crabtree effect) and human cancer cells (the Warburg effect). At the root of both effects is accelerated metabolic flow through glycolysis which leads to overflows of ethanol and lactic acid, respectively. It has been proposed that enhanced glycolytic flow in cancer cells is triggered by the altered kinetic characteristics of the key glycolytic regulatory enzyme 6-phosphofructo-1-kinase (Pfk). Through a posttranslational modification, highly active shorter Pfk-M fragments, which are resistant to feedback inhibition, are formed after the proteolytic cleavage of the C-terminus of the native human Pfk-M. Alternatively, enhanced glycolysis is triggered by optimal growth conditions in the yeast Saccharomyces cerevisiae. ResultsTo assess the deregulation of glycolysis in yeast cells, the sfPFKM gene encoding highly active human shorter Pfk-M fragments was introduced into pfk-null S. cerevisiae. No growth of the transformants with the sfPFKM gene was observed on glucose and fructose. Glucose even induced rapid deactivation of Pfk1 activities in such transformants. However, Pfk1 activities of the sfPFKM transformants were detected in maltose medium, but the growth in maltose was possible only after the addition of 10 mM of ethanol to the medium. Ethanol seemed to alleviate the severely unbalanced NADH/NADPH ratio in the sfPFKM cells. However, the transformants carrying modified Pfk-M enzymes grew faster than the transformants with the human native human Pfk-M enzyme in a narrow ecological niche with a low maltose concentration medium that was further improved by additional modifications. Interestingly, periodic extracellular accumulation of phenylacetaldehyde was detected during the growth of the strain with modified Pfk-M but not with the strain encoding the human native enzyme.ConclusionsHighly active cancer-specific shorter Pfk-M fragments appear to trigger several controlling mechanisms in the primary metabolism of yeast S. cerevisiae cells. These results suggest more complex metabolic regulation is present in S. cerevisiae as free living unicellular eukaryotic organisms in comparison to metazoan human cells. However, increased productivity under broader growth conditions may be achieved if more gene engineering is performed to reduce or omit several controlling mechanisms.Electronic supplementary materialThe online version of this article (doi:10.1186/s12896-017-0362-5) contains supplementary material, which is available to authorized users.

show abstract

“…In any case, the high-affinity iron transport system seems to be the essential one operating both in respiratory and fermentative conditions, which explains that even in SD-glucose medium Aft1-lacking cells grow slower than wild-type ones. Besides affecting such diverse physiological processes as cytochrome or deoxyribonucleotide biosynthesis (Wrigglesworth and Baum, 1980), low intracellular iron levels could also alter glycolysis flux through the posttranscriptional positive regulatory role of this metal on TPI3-coded triosephosphate isomerase and THD3-coded glyceraldehyde-3-phosphate isomerase (Krieger and Ernst, 1994).…”

Section: Discussionmentioning

confidence: 99%

The AFT1 Transcriptional Factor is Differentially Required for Expression of High‐Affinity Iron Uptake Genes in Saccharomyces cerevisiae

Casas

Aldea

Espinet

et al. 1997

Yeast

View full text Add to dashboard Cite

High-affinity iron uptake in Saccharomyces cerevisiae involves the extracytoplasmic reduction of ferric ions by FRE1 and FRE2 reductases. Ferrous ions are then transported across the plasma membrane through the FET3 oxidase-FTR1 permease complex. Expression of the high-affinity iron uptake genes is induced upon iron deprivation. We demonstrate that AFT1 is differentially involved in such regulation. Aft1 protein is required for maintaining detectable non-induced levels of FET3 expression and for induction of FRE2 in iron starvation conditions. On the contrary, FRE1 mRNA induction is normal in the absence of Aft1, although the existence of AFT1 point mutations causing constitutive expression of FRE1 (Yamaguchi-Iwai et al., EMBO J. 14: [1231][1232][1233][1234][1235][1236][1237][1238][1239] 1995) indicates that Aft1 may also participate in FRE1 expression in a dispensable way. The alterations in the basal levels of expression of the high-affinity iron uptake genes may explain why the AFT1 mutant is unable to grow on respirable carbon sources. Overexpression of AFT1 leads to growth arrest at the G 1 stage of the cell cycle. Aft1 is a transcriptional activator that would be part of the different transcriptional complexes interacting with the promoter of the high-affinity iron uptake genes. Aft1 displays phosphorylation modifications depending on the growth stage of the cells, and it might link induction of genes for iron uptake to other metabolically dominant requirements for cell growth.

show abstract

Iron regulation of triosephosphate isomerase transcript stability in the yeast Saccharomyces cerevisiae

Cited by 10 publications

References 24 publications

Gene Expression Analysis of Cold and Freeze Stress in Baker's Yeast

Gene Expression Analysis of Cold and Freeze Stress in Baker's Yeast

Effect of the cancer specific shorter form of human 6-phosphofructo-1-kinase on the metabolism of the yeast Saccharomyces cerevisiae

The AFT1 Transcriptional Factor is Differentially Required for Expression of High‐Affinity Iron Uptake Genes in Saccharomyces cerevisiae

Contact Info

Product

Resources

About