scholarly journals ATR1, a Saccharomyces cerevisiae gene encoding a transmembrane protein required for aminotriazole resistance.

1988 ◽  
Vol 8 (2) ◽  
pp. 664-673 ◽  
Author(s):  
S Kanazawa ◽  
M Driscoll ◽  
K Struhl
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acid ◽  
Binding Site ◽  
Transmembrane Protein ◽  
Wild Type ◽  
Atp Binding Site ◽  
Activator Protein ◽  
Transcriptional Activator Protein ◽  
Multiple Copies ◽  
Type Strains

In Saccharomyces cerevisiae, 3-amino-1,2,4-triazole (aminotriazole) competitively inhibits the activity of imidazoleglycerolphosphate dehydratase, the product of the HIS3 gene. Wild-type strains are able to grow in the presence of 10 mM aminotriazole because they induce the level of imidazoleglycerolphosphate dehydratase. However, strains containing gcn4 mutations are unable to grow in medium containing aminotriazole because they lack the GCN4 transcriptional activator protein necessary for the coordinate induction of HIS3 and other amino acid biosynthetic genes. Here, we isolated a new gene, designated ATR1, which when present in multiple copies per cell allowed gcn4 mutant strains to grow in the presence of aminotriazole. In wild-type strains, multiple copies of ATR1 permitted growth at extremely high concentrations of aminotriazole (80 mM), whereas a chromosomal deletion of ATR1 caused growth inhibition at very low concentrations (5 mM). When radioactive aminotriazole was added exogenously, cells with multiple copies of ATR1 accumulated less aminotriazole than wild-type cells, whereas cells with the atr1 deletion mutation retained more aminotriazole. Unlike the mammalian mdr or yeast PDR genes that confer resistance to many drugs, ATR1 appears to confer resistance only to aminotriazole. Genetic analysis, mRNA mapping, and DNA sequencing revealed that (i) the primary translation product of ATR1 contains 547 amino acids, (ii) ATR1 transcription is induced by aminotriazole, and (iii) the ATR1 promoter region contains a binding site for the GCN4 activator protein. The deduced amino acid sequence suggests that ATR1 protein is very hydrophobic with many membrane-spanning regions, has several potential glycosylation sites, and may contain an ATP-binding site. We suggest that ATR1 encodes a membrane-associated component of the machinery responsible for pumping aminotriazole (and possibly other toxic compounds) out of the cell.

ATR1, a Saccharomyces cerevisiae gene encoding a transmembrane protein required for aminotriazole resistance

1988 ◽  
Vol 8 (2) ◽  
pp. 664-673
Author(s):  
S Kanazawa ◽  
M Driscoll ◽  
K Struhl
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acid ◽  
Binding Site ◽  
Transmembrane Protein ◽  
Wild Type ◽  
Atp Binding Site ◽  
Activator Protein ◽  
Transcriptional Activator Protein ◽  
Multiple Copies ◽  
Type Strains

In Saccharomyces cerevisiae, 3-amino-1,2,4-triazole (aminotriazole) competitively inhibits the activity of imidazoleglycerolphosphate dehydratase, the product of the HIS3 gene. Wild-type strains are able to grow in the presence of 10 mM aminotriazole because they induce the level of imidazoleglycerolphosphate dehydratase. However, strains containing gcn4 mutations are unable to grow in medium containing aminotriazole because they lack the GCN4 transcriptional activator protein necessary for the coordinate induction of HIS3 and other amino acid biosynthetic genes. Here, we isolated a new gene, designated ATR1, which when present in multiple copies per cell allowed gcn4 mutant strains to grow in the presence of aminotriazole. In wild-type strains, multiple copies of ATR1 permitted growth at extremely high concentrations of aminotriazole (80 mM), whereas a chromosomal deletion of ATR1 caused growth inhibition at very low concentrations (5 mM). When radioactive aminotriazole was added exogenously, cells with multiple copies of ATR1 accumulated less aminotriazole than wild-type cells, whereas cells with the atr1 deletion mutation retained more aminotriazole. Unlike the mammalian mdr or yeast PDR genes that confer resistance to many drugs, ATR1 appears to confer resistance only to aminotriazole. Genetic analysis, mRNA mapping, and DNA sequencing revealed that (i) the primary translation product of ATR1 contains 547 amino acids, (ii) ATR1 transcription is induced by aminotriazole, and (iii) the ATR1 promoter region contains a binding site for the GCN4 activator protein. The deduced amino acid sequence suggests that ATR1 protein is very hydrophobic with many membrane-spanning regions, has several potential glycosylation sites, and may contain an ATP-binding site. We suggest that ATR1 encodes a membrane-associated component of the machinery responsible for pumping aminotriazole (and possibly other toxic compounds) out of the cell.

scholarly journals RNA polymerase II mutants defective in transcription of a subset of genes.

1990 ◽  
Vol 10 (3) ◽  
pp. 1010-1016 ◽  
Author(s):  
C Scafe ◽  
M Nonet ◽  
R A Young
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acid ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Amino Acid Residue ◽  
Permissive Temperature ◽  
Nonpermissive Temperature ◽  
Wild Type ◽  
Specific Mrnas ◽  
Type Strains

Saccharomyces cerevisiae RNA polymerase II conditional mutants that selectively disrupt the synthesis of specific mRNAs were isolated. At the permissive temperature, several of the mutants were inositol auxotrophs as a result of inadequate induction of INO1 transcription. The transcriptional defects exhibited by one of these Ino- mutants (rpb2-2) were further investigated. The induction of GAL10 and HIS4 transcription in rpb2-2 strains was similar to that of wild-type strains, in contrast to the lack of induction of INO1 transcription. When shifted to the nonpermissive temperature, cells containing rpb2-2 continued to accumulate some mRNAs but not others. Together, these results indicate that transcription of specific genes can be disrupted by RNA polymerase II mutations. The rpb2-2 allele alters an amino acid residue that occurs in a highly conserved segment of the RPB2 protein and that is shared by homologous subunits in other species.

scholarly journals The general control activator protein GCN4 is essential for a basal level of ARO3 gene expression in Saccharomyces cerevisiae.

1989 ◽  
Vol 9 (1) ◽  
pp. 144-151 ◽  
Author(s):  
G Paravicini ◽  
H U Mösch ◽  
T Schmidheini ◽  
G Braus
Keyword(s):  
Gene Expression ◽  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Amino Acid ◽  
Gene Product ◽  
Slow Growth ◽  
Amino Acid Starvation ◽  
Wild Type ◽  
General Control ◽  
Activator Protein

The ARO3 gene encodes one of two 3-deoxy-D-arabino-heptulosonate-7-phosphate isoenzymes in Saccharomyces cerevisiae catalyzing the first step in the biosynthesis of aromatic amino acids. The ARO3-encoded 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (EC 4.1.2.15) is feedback inhibited by phenylalanine; its isoenzyme, the ARO4 gene product, is inhibited by tyrosine. Both genes ARO3 and ARO4 are strongly regulated under the general control regulatory system. Cells carrying only one intact isogene are phenotypically indistinguishable from a wild-type strain when grown on minimal medium. The complete functional ARO3 promoter comprises 231 base pairs and contains only one TGACTA binding site for the general control activator protein GCN4. Mutating this element to TTACTA inhibits binding of GCN4 and results in a decreased basal level of ARO3 gene product and slow growth of a strain defective in its isogene ARO4. In addition, ARO3 gene expression cannot be elevated under amino acid starvation conditions. An ARO3 aro4 strain with gcn4 genetic background has the same phenotype of low ARO3 gene expression and slow growth. The amount of GCN4 protein present in repressed wild-type cells therefore seems to contribute to a basal level of ARO3 gene expression. The general control activator GCN4 has thus two functions: (i) to maintain a basal level of ARO3 transcription (basal control) in the presence of amino acids and (ii) to derepress the ARO3 gene to a higher transcription rate under amino acid starvation (general control).

The general control activator protein GCN4 is essential for a basal level of ARO3 gene expression in Saccharomyces cerevisiae

1989 ◽  
Vol 9 (1) ◽  
pp. 144-151
Author(s):  
G Paravicini ◽  
H U Mösch ◽  
T Schmidheini ◽  
G Braus
Keyword(s):  
Gene Expression ◽  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Amino Acid ◽  
Gene Product ◽  
Slow Growth ◽  
Amino Acid Starvation ◽  
Wild Type ◽  
General Control ◽  
Activator Protein

The ARO3 gene encodes one of two 3-deoxy-D-arabino-heptulosonate-7-phosphate isoenzymes in Saccharomyces cerevisiae catalyzing the first step in the biosynthesis of aromatic amino acids. The ARO3-encoded 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (EC 4.1.2.15) is feedback inhibited by phenylalanine; its isoenzyme, the ARO4 gene product, is inhibited by tyrosine. Both genes ARO3 and ARO4 are strongly regulated under the general control regulatory system. Cells carrying only one intact isogene are phenotypically indistinguishable from a wild-type strain when grown on minimal medium. The complete functional ARO3 promoter comprises 231 base pairs and contains only one TGACTA binding site for the general control activator protein GCN4. Mutating this element to TTACTA inhibits binding of GCN4 and results in a decreased basal level of ARO3 gene product and slow growth of a strain defective in its isogene ARO4. In addition, ARO3 gene expression cannot be elevated under amino acid starvation conditions. An ARO3 aro4 strain with gcn4 genetic background has the same phenotype of low ARO3 gene expression and slow growth. The amount of GCN4 protein present in repressed wild-type cells therefore seems to contribute to a basal level of ARO3 gene expression. The general control activator GCN4 has thus two functions: (i) to maintain a basal level of ARO3 transcription (basal control) in the presence of amino acids and (ii) to derepress the ARO3 gene to a higher transcription rate under amino acid starvation (general control).

RNA polymerase II mutants defective in transcription of a subset of genes

1990 ◽  
Vol 10 (3) ◽  
pp. 1010-1016
Author(s):  
C Scafe ◽  
M Nonet ◽  
R A Young
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acid ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Amino Acid Residue ◽  
Permissive Temperature ◽  
Nonpermissive Temperature ◽  
Wild Type ◽  
Specific Mrnas ◽  
Type Strains

Saccharomyces cerevisiae RNA polymerase II conditional mutants that selectively disrupt the synthesis of specific mRNAs were isolated. At the permissive temperature, several of the mutants were inositol auxotrophs as a result of inadequate induction of INO1 transcription. The transcriptional defects exhibited by one of these Ino- mutants (rpb2-2) were further investigated. The induction of GAL10 and HIS4 transcription in rpb2-2 strains was similar to that of wild-type strains, in contrast to the lack of induction of INO1 transcription. When shifted to the nonpermissive temperature, cells containing rpb2-2 continued to accumulate some mRNAs but not others. Together, these results indicate that transcription of specific genes can be disrupted by RNA polymerase II mutations. The rpb2-2 allele alters an amino acid residue that occurs in a highly conserved segment of the RPB2 protein and that is shared by homologous subunits in other species.

scholarly journals Influences of Histone Stoichiometry on the Target Site Preference of Retrotransposons Ty1 and Ty2 in Saccharomyces cerevisiae

Genetics ◽  
1996 ◽  
Vol 142 (3) ◽  
pp. 761-776 ◽  
Author(s):  
Lori A Rinckel ◽  
David J Garfinkel
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Promoter Region ◽  
Target Site ◽  
Site Preference ◽  
Wild Type ◽  
Histone Proteins ◽  
Protein Levels ◽  
In The Wild ◽  
Type Strains ◽  
Orientation Bias

Abstract In Saccharomyces cerevisiae, the target site specificity of the retrotransposon Ty1 appears to involve the Ty integration complex recognizing chromatin structures. To determine whether changes in chromatin structure affect Ty1 and Ty2 target site preference, we analyzed Ty transposition at the CAN1 locus in mutants containing altered levels of histone proteins. A Δhta1-htb1 mutant with decreased levels of H2A and H2B histone proteins showed a pattern of Ty1 and Ty2 insertions at CAN1 that was significantly different from that of both the wild-type and a Δhta2-htb2 mutant, which does not have altered histone protein levels. Altered levels of H2A and H2B proteins disrupted a dramatic orientation bias in the CAN1 promoter region. In the wild-type strains, few Ty1 and Ty2 insertions in the promoter region were oriented opposite to the direction of CAN1 transcription. In the Δhta1-htb1 background, however, numerous Ty1 and Ty2 insertions were in the opposite orientation clustered within the TATA region. This altered insertion pattern does not appear to be due to a bias caused by selecting canavanine resistant isolates in the different HTA1-HTB1 backgrounds. Our results suggest that reduced levels of histone proteins alter Ty target site preference and disrupt an asymmetric Ty insertion pattern.

scholarly journals DAF1, a mutant gene affecting size control, pheromone arrest, and cell cycle kinetics of Saccharomyces cerevisiae.

1988 ◽  
Vol 8 (11) ◽  
pp. 4675-4684 ◽  
Author(s):  
F R Cross
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Critical Size ◽  
Size Control ◽  
Mutant Gene ◽  
G1 Phase ◽  
Wild Type ◽  
Alpha Factor ◽  
Multiple Copies ◽  
Kinetics Of

The mating pheromone alpha-factor arrests Saccharomyces cerevisiae MATa cells in the G1 phase of the cell cycle. Size control is also exerted in G1, since cells do not exit G1 until they have attained a critical size. A dominant mutation (DAF1-1) which causes both alpha-factor resistance and small cell size (volume about 0.6-fold that of the wild type) has been isolated and characterized genetically and by molecular cloning. Several alpha-factor-induced mRNAs were induced equivalently in daf1+ and DAF1-1 cells. The DAF1-1 mutation consisted of a termination codon two-thirds of the way through the daf1+ coding sequence. A chromosomal deletion of DAF1 produced by gene transplacement increased cell volume about 1.5-fold; thus, DAF1-1 may be a hyperactive or deregulated allele of a nonessential gene involved in G1 size control. Multiple copies of DAF1-1 also greatly reduced the duration of the G1 phase of the cell cycle.

A tyrosine-phosphorylated carboxy-terminal peptide of the fibroblast growth factor receptor (Flg) is a binding site for the SH2 domain of phospholipase C-gamma 1

1991 ◽  
Vol 11 (10) ◽  
pp. 5068-5078
Author(s):  
M Mohammadi ◽  
A M Honegger ◽  
D Rotin ◽  
R Fischer ◽  
F Bellot ◽  
...  
Keyword(s):  
Amino Acid ◽  
Growth Factor ◽  
Binding Site ◽  
Fibroblast Growth Factor ◽  
Tryptic Peptide ◽  
Fibroblast Growth Factor Receptor ◽  
Growth Factor Receptor ◽  
Sh2 Domain ◽  
Fibroblast Growth ◽  
Wild Type

Phospholipase C-gamma (PLC-gamma) is a substrate of the fibroblast growth factor receptor (FGFR; encoded by the flg gene) and other receptors with tyrosine kinase activity. It has been demonstrated that the src homology region 2 (SH2 domain) of PLC-gamma and of other signalling molecules such as GTPase-activating protein and phosphatidylinositol 3-kinase-associated p85 direct their binding toward tyrosine-autophosphorylated regions of the epidermal growth factor or platelet-derived growth factor receptor. In this report, we describe the identification of Tyr-766 as an autophosphorylation site of flg-encoded FGFR by direct sequencing of a tyrosine-phosphorylated tryptic peptide isolated from the cytoplasmic domain of FGFR expressed in Escherichia coli. The same phosphopeptide was found in wild-type FGFR phosphorylated either in vitro or in living cells. Like other growth factor receptors, tyrosine-phosphorylated wild-type FGFR or its cytoplasmic domain becomes associated with intact PLC-gamma or with a fusion protein containing the SH2 domain of PLC-gamma. To delineate the site of association, we have examined the capacity of a 28-amino-acid tryptic peptide containing phosphorylated Tyr-766 to bind to various constructs containing SH2 and other domains of PLC-gamma. It is demonstrated that the tyrosine-phosphorylated peptide binds specifically to the SH2 domain but not to the SH3 domain or other regions of PLC-gamma. Hence, Tyr-766 and its flanking sequences represent a major binding site in FGFR for PLC-gamma. Alignment of the amino acid sequences surrounding Tyr-766 with corresponding regions of other FGFRs revealed conserved tyrosine residues in all known members of the FGFR family. We propose that homologous tyrosine-phosphorylated regions in other FGFRs also function as binding sites for PLC-gamma and therefore are involved in coupling to phosphatidylinositol breakdown.

Multiple GCD genes required for repression of GCN4, a transcriptional activator of amino acid biosynthetic genes in Saccharomyces cerevisiae

1986 ◽  
Vol 6 (11) ◽  
pp. 3990-3998
Author(s):  
S Harashima ◽  
A G Hinnebusch
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acid ◽  
Lacz Gene ◽  
Gene Products ◽  
Wild Type ◽  
Double Mutation ◽  
Double Stranded Rna ◽  
Amino Acid Availability ◽  
Genes Encoding ◽  
New Alleles

GCN4 encodes a positive regulator of multiple unlinked genes encoding amino acid biosynthetic enzymes in Saccharomyces cerevisiae. Expression of GCN4 is coupled to amino acid availability by a control mechanism involving GCD1 as a negative effector and GCN1, GCN2, and GCN3 as positive effectors of GCN4 expression. We used reversion of a gcn2 gcn3 double mutation to isolate new alleles of GCD1 and mutations in four additional GCD genes which we designate GCD10, GCD11, GCD12, and GCD13. All of the mutations lead to constitutive derepression of HIS4 transcription in the absence of the GCN2+ and GCN3+ alleles. By contrast, the gcd mutations require the wild-type GCN4 allele for their derepressing effect, suggesting that each acts by influencing the level of GCN4 activity in the cell. Consistent with this interpretation, mutations in each GCD gene lead to constitutive derepression of a GCN4::lacZ gene fusion. Thus, at least five gene products are required to maintain the normal repressed level of GCN4 expression in nonstarvation conditions. Interestingly, the gcd mutations are pleiotropic and also affect growth rate in nonstarvation conditions. In addition, certain alleles lead to a loss of M double-stranded RNA required for the killer phenotype. This pleiotropy suggests that the GCD gene products contribute to an essential cellular function, in addition to, or in conjunction with, their role in GCN4 regulation.

Bioreduction of Some Common Carbonylic Compounds Mediated by Yeasts

2010 ◽  
Vol 65 (1-2) ◽  
pp. 1-9 ◽  
Author(s):  
Javier Silva ◽  
Julio Alarcón ◽  
Sergio A. Aguila ◽  
Joel B. Alderete
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Pichia Pastoris ◽  
Aqueous Medium ◽  
Ethyl Acetoacetate ◽  
Enantiomeric Excess ◽  
Optically Active ◽  
Environmentally Benign ◽  
Wild Type ◽  
Regeneration System ◽  
Type Strains

Bioreduction of several prochiral carbonylic compounds such as acetophenone (1), ethyl acetoacetate (2) and ethyl phenylpropionate (3) to the corresponding optically active secalcohols 1a - 3a was performed using wild-type strains of Pichia pastoris UBB 1500, Rhodotorula sp., and Saccharomyces cerevisiae. The reductions showed moderate to excellent conversion and high enantiomeric excess, in an extremely mild and environmentally benign manner in aqueous medium, using glucose as cofactor regeneration system. The obtained alcohols follow Prelog’s rule, but in the reduction of 1 with P. pastoris UBB 1500 the anti- Prelog enantiopreference was observed

Sign in / Sign up

Export Citation Format

Share Document