Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.1.1.1 (alcohol dehydrogenase)
 9,284 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Starting with yeast cells lacking the constitutive alcohol dehydrogenase activity (ADHI), mutants with partially glucose-insensitive formation of ADHII were isolated. Genetic analysis showed that four mutants (designated ADR3c) were linked to the ADHII-structural gene, ADR2, and were cis-dominant. On derepression, two of them produced elevated ADHII-levels, indicating a promotor function of the altered controlling site. The other ADR3c-mutant alleles affected the ADHII-subunit association in diploids carrying two electrophoretically distinct alleles of the structural gene ADR2. Twelve semidominant constitutive mutants could be attributed to gene ADR1 (ADR1c-alleles) previously identified by recessive mutants with blocked derepression. This suggested a positive regulatory role of the ADR1 gene product on the expression of the ADHII-structural gene. A pleiotropic mutation ccr1 (Ciriacy, 1977) was epistatic over glucose-resistant ADHII-formation caused by ADR1c-alleles. From this it was concluded that CCR1 specifies for a product co-activating the structural gene or modifying the ADR1-gene product. A further regulatory element (gene designation ADR4) not linked to the structural gene could be identified upon isolation of recessive constitutive mutants adr4 from a ccr1 ADR1c-double mutant.
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PMID:Isolation and characterization of further cis- and trans-acting regulatory elements involved in the synthesis of glucose-repressible alcohol dehydrogenase (ADHII) in Saccharomyces cerevisiae. 39 42

The transcriptional activator ADR1 from Saccharomyces cerevisiae is a postulated DNA-binding protein that controls the expression of the glucose-repressible alcohol dehydrogenase (ADH2). Carboxy-terminal deletions of the ADR1 protein (1,323 amino acids in length) were used to localize its functional regions. The transcriptional activation region was localized to the N-terminal 220 amino acids of ADR1 containing two DNA-binding zinc finger motifs. In addition to the N terminus, a large part of the ADR1 sequence was shown to be essential for complete activation of ADH2. Deletion of the putative phosphorylation region, defined by ADR1c mutations that overcome glucose repression, did not render ADH2 expression insensitive to glucose repression. Instead, this region (amino acids 220 through 253) was found to be required by ADR1 to bypass glucose repression. These results suggest that ADR1c mutations enhance ADR1 function, rather than block an interaction of the putative phosphorylation region with a repressor molecule. Furthermore, the protein kinase CCR1 was shown to affect ADH2 expression when the putative phosphorylation region was removed, indicating that CCR1 does not act solely through this region. A functional ADR1 gene was also found to be necessary for growth on glycerol-containing medium. The N-terminal 506 amino acids of ADR1 were required for this newly identified function, indicating that ADH2 activation and glycerol growth are controlled by separate regions of ADR1.
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PMID:Identification of functional regions in the yeast transcriptional activator ADR1. 329 Jun 50

The dosage of the transcriptional activator ADR1 was varied in order to study the regulation of the glucose-repressible alcohol dehydrogenase (ADH II) from Saccharomyces cerevisiae. ADH II activity during glucose growth conditions was shown to increase linearly with increasing ADR1 gene dosage. In contrast, under derepressed growth conditions a 100-fold increase in ADR1 copy number resulted in only a 4-fold increase in ADH II expression. Saturation of ADH II gene expression by ADR1 under derepressed conditions was shown not to result from decreased ADR1 transcription. Increases in ADH2 gene dosage in conjunction with high ADR1 gene dosages resulted in increased ADH II activity, indicating that ADH2 was the limiting factor during derepression. Under glucose-repressed conditions the activator CCR1 was not required for ADR1 activity. During derepression increasing ADR1 dosage could partially compensate for a CCR1 defect. Increasing CCR1 gene dosage, however, had no effect on ADH2 expression regardless of the ADR1 allele present. These results suggest that CCR1 acts through ADR1 in controlling ADH2 expression. It was also observed that high numbers of ADR1, or a few copies of ADR1-5c, substantially increased the cell doubling time under ethanol growth conditions, indicating that increased ADR1 activity is toxic.
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PMID:The effects of ADR1 and CCR1 gene dosage on the regulation of the glucose-repressible alcohol dehydrogenase from Saccharomyces cerevisiae. 330 3

Recessive mutations in two negative control elements, CRE1 and CRE2, have been obtained that allow the glucose-repressible alcohol dehydrogenase (ADHII) of yeast to escape repression by glucose. Both the cre1 and cre2 alleles affected ADHII synthesis irrespective of the allele of the positive effector, ADR1. However, for complete derepression of ADHII synthesis, a wild-type ADR1 gene was required. Neither the cre1 nor cre2 alleles affected the expression of several other glucose-repressible enzymes. A third locus, CCR4, was identified by recessive mutations that suppressed the cre1 and cre2 phenotypes. The ccr4 allele blocked the derepression of ADHII and several other glucose-repressible enzymes, indicating that the CCR4 gene is a positive control element. The ccr4 allele had no effect on the repression of ADHII when it was combined with the ADR1-5c allele, whereas the phenotypically similar ccr1 allele, which partially suppresses ADR1-5c, did not suppress the cre1 or cre2 phenotype. Complementation studies also indicated that ccr1 and snf1 are allelic. A model of ADHII regulation is proposed in which both ADR1 and CCR4 are required for ADHII expression. CRE1 and CRE2 negatively control CCR4, whereas CCR1 is required for ADR1 function.
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PMID:Identification of new genes involved in the regulation of yeast alcohol dehydrogenase II. 639 16