Gene-enzyme relationship in the sulfate assimilation pathway of Saccharomyces cerevisiae. Study of the 3'-phosphoadenylylsulfate reductase structural gene.

ABSTRACT Despite a century of research and increasing environmental and human health concerns, the mechanistic basis of the toxicity of derivatives of the metalloid tellurium, Te, in particular the oxyanion tellurite, Te(IV), remains unsolved. Here, we provide an unbiased view of the mechanisms of tellurium metabolism in the yeast Saccharomyces cerevisiae by measuring deviations in Te-related traits of a complete collection of gene knockout mutants. Reduction of Te(IV) and intracellular accumulation as metallic tellurium strongly correlated with loss of cellular fitness, suggesting that Te(IV) reduction and toxicity are causally linked. The sulfate assimilation pathway upstream of Met17, in particular, the sulfite reductase and its cofactor siroheme, was shown to be central to tellurite toxicity and its reduction to elemental tellurium. Gene knockout mutants with altered Te(IV) tolerance also showed a similar deviation in tolerance to both selenite and, interestingly, selenomethionine, suggesting that the toxicity of these agents stems from a common mechanism. We also show that Te(IV) reduction and toxicity in yeast is partially mediated via a mitochondrial respiratory mechanism that does not encompass the generation of substantial oxidative stress. The results reported here represent a robust base from which to attack the mechanistic details of Te(IV) toxicity and reduction in a eukaryotic organism.

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SAM1, the structural gene for one of the S-adenosylmethionine synthetases in Saccharomyces cerevisiae. Sequence and expression.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)49312-x ◽

1987 ◽

Vol 262 (34) ◽

pp. 16704-16709 ◽

Cited By ~ 3

Author(s):

D Thomas ◽

Y Surdin-Kerjan

Keyword(s):

Saccharomyces Cerevisiae ◽

Structural Gene

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Protease B of Saccharomyces cerevisiae: Isolation and Regulation of the PRB1 Structural Gene

Genetics ◽

10.1093/genetics/115.2.255 ◽

1987 ◽

Vol 115 (2) ◽

pp. 255-263 ◽

Cited By ~ 1

Author(s):

Charles M Moehle ◽

Martha W Aynardi ◽

Michael R Kolodny ◽

Frances J Park ◽

Elizabeth W Jones

Keyword(s):

Saccharomyces Cerevisiae ◽

Molecular Weight ◽

Structural Gene ◽

Genomic Library ◽

Time Lag ◽

Proteolytic Processing ◽

Coding Region ◽

Protease B ◽

Endonuclease Mapping ◽

Protein Molecular Weight

ABSTRACT We have isolated the structural gene, PRB1, for the vacuolar protease B of Saccharomyces cerevisiae from a genomic library by complementation of the prb1-1122 mutation. Deletion analysis localized the complementing activity to a 3.2-kilobase pair XhoI-HindIII restriction enzyme fragment. The fragment was used to identify a 2.3-kilobase mRNA. S1 endonuclease mapping indicated that the mRNA and the gene were colinear. No introns were detected. The mRNA is of sufficient size to encode a protein of about 69,000 molecular weight, a number much larger than either the mature enzyme (≃30,000 protein molecular weight) or the sole reported precursor (≃39,000 protein molecular weight). These results suggest that proteolytic processing steps beyond that thought to be catalyzed by protease A may be required to convert the initial glycosylated translation product into mature protease B. The PRB1 mRNA is made in substantial amounts only when the cells have exhausted the glucose supply and enter the diauxic plateau. There is an extended time lag between PRB1 transcription and expression of protease B activity. A deletion that removes about 83% of the coding region was constructed as a diploid heterozygote. Spores bearing the deletion germinate, grow at normal rates into colonies, and have no obvious phenotype beyond protease B deficiency.

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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):

Saccharomyces Cerevisiae ◽

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.

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PEP4 gene of Saccharomyces cerevisiae encodes proteinase A, a vacuolar enzyme required for processing of vacuolar precursors

Molecular and Cellular Biology ◽

10.1128/mcb.6.7.2490-2499.1986 ◽

1986 ◽

Vol 6 (7) ◽

pp. 2490-2499

Author(s):

G Ammerer ◽

C P Hunter ◽

J H Rothman ◽

G C Saari ◽

L A Valls ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Amino Acid ◽

Structural Gene ◽

Yeast Cells ◽

Linkage Data ◽

Predicted Amino Acid Sequence ◽

Multicopy Plasmid ◽

Proteinase A ◽

Pep4 Gene ◽

Cloned Gene

The proteinase A structural gene of Saccharomyces cerevisiae was cloned by using an immunological screening procedure that allows detection of yeast cells which are aberrantly secreting vacuolar proteins (J. H. Rothman, C. P. Hunter, L. A. Valls, and T. H. Stevens, Proc. Natl. Acad. Sci. USA, 83:3248-3252, 1986). A second cloned gene was obtained on a multicopy plasmid by complementation of a pep4-3 mutation. The nucleotide sequences of these two genes were determined independently and were found to be identical. The predicted amino acid sequence of the cloned gene suggests that proteinase A is synthesized as a 405-amino-acid precursor which is proteolytically converted to the 329-amino-acid mature enzyme. Proteinase A shows substantial homology to mammalian aspartyl proteases, such as pepsin, renin, and cathepsin D. The similarities may reflect not only analogous functions but also similar processing and intracellular targeting mechanisms for the two proteins. The cloned proteinase A structural gene, even when it is carried on a single-copy plasmid, complements the deficiency in several vacuolar hydrolase activities that is observed in a pep4 mutant. A strain carrying a deletion in the genomic copy of the gene fails to complement a pep4 mutant of the opposite mating type. Genetic linkage data demonstrate that integrated copies of the cloned proteinase A structural gene map to the PEP4 locus. Thus, the PEP4 gene encodes a vacuolar aspartyl protease, proteinase A, that is required for the in vivo processing of a number of vacuolar zymogens.

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Molecular genetics of met17 and met25 mutants of Saccharomyces cerevisiae: Intragenic complementation between mutations of a single structural gene

MGG Molecular & General Genetics ◽

10.1007/bf00331505 ◽

1987 ◽

Vol 207 (1) ◽

pp. 165-170 ◽

Cited By ~ 13

Author(s):

Richard D'Andrea ◽

Yolande Surdin-Kerjan ◽

Glenn Pure ◽

Hélène Cherest

Keyword(s):

Saccharomyces Cerevisiae ◽

Molecular Genetics ◽

Structural Gene ◽

Intragenic Complementation

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Physical evidence for a Saccharomyces cerevisiae transposable element which carries the his4C gene.

Molecular and Cellular Biology ◽

10.1128/mcb.1.4.381 ◽

1981 ◽

Vol 1 (4) ◽

pp. 381-386 ◽

Cited By ~ 2

Author(s):

F de Bruijn ◽

H Greer

Keyword(s):

Saccharomyces Cerevisiae ◽

Transposable Element ◽

Structural Gene ◽

Deoxyribonucleic Acid ◽

Physical Evidence ◽

Precise Excision ◽

Mutator Activity ◽

New Location

A Saccharomyces cerevisiae transposable element which carries the his4C structural gene and which is capable of transposition, excision, and mutator activity is described. Physical evidence is presented for transposition of the his4C deoxyribonucleic acid sequences to a new location in the genome and for precise excision of these transposed deoxyribonucleic acid sequences in spontaneous his4C- segregants.

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The Recovery from Sulfur Starvation is Independent from the mRNA Degradation Initiation Enzyme PARN in Arabidopsis

Plants ◽

10.3390/plants8100380 ◽

2019 ◽

Vol 8 (10) ◽

pp. 380 ◽

Cited By ~ 1

Author(s):

Armbruster ◽

Uslu ◽

Wirtz ◽

Hell

Keyword(s):

Stress Responses ◽

Splice Variants ◽

Marker Genes ◽

Sulfate Assimilation ◽

Sulfur Deficiency ◽

Protective Measures ◽

Sulfur Starvation ◽

Sulfate Assimilation Pathway ◽

Growth Promoting

When plants are exposed to sulfur limitation, they upregulate the sulfate assimilation pathway at the expense of growth-promoting measures. Upon cessation of the stress, however, protective measures are deactivated, and growth is restored. In accordance with these findings, transcripts of sulfur-deficiency marker genes are rapidly degraded when starved plants are resupplied with sulfur. Yet it remains unclear which enzymes are responsible for the degradation of transcripts during the recovery from starvation. In eukaryotes, mRNA decay is often initiated by the cleavage of poly(A) tails via deadenylases. As mutations in the poly(A) ribonuclease PARN have been linked to altered abiotic stress responses in Arabidopsis thaliana, we investigated the role of PARN in the recovery from sulfur starvation. Despite the presence of putative PARN-recruiting AU-rich elements in sulfur-responsive transcripts, sulfur-depleted PARN hypomorphic mutants were able to reset their transcriptome to pre-starvation conditions just as readily as wildtype plants. Currently, the subcellular localization of PARN is disputed, with studies reporting both nuclear and cytosolic localization. We detected PARN in cytoplasmic speckles and reconciled the diverging views in literature by identifying two PARN splice variants whose predicted localization is in agreement with those observations.

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