Saccharomyces cerevisiae alcohol dehydrogenase 1 (ADH1) promoter, long form
Full-length promoter of the S. cerevisiae ADH1 gene, encoding the fermentative isozyme alcohol dehydrogenase I. Drives constitutive, moderate-to-strong transcription in yeast and is one of the most widely used constitutive promoters for recombinant protein expression, alongside GPD/TDH3 and TEF1. This is the long (~1.5 kb) upstream form; adh1-medium and adh1-short are shorter truncations of the same promoter region.
Origin: Saccharomyces cerevisiae, long (~1.5 kb) upstream form
Characteristics
Contains the full native upstream regulatory region of ADH1, including its UAS1/UAS2 activating sequences. Drives constitutive expression throughout growth on glucose, but in comparative reporter assays against other native S. cerevisiae glycolytic and translation-machinery promoters, ADH1 consistently produces lower output than TEF1 or GPD/TDH3. Its activity is also markedly more sensitive to gene dosage than GPD, showing roughly a 30-fold difference in beta-galactosidase activity between high-copy (2-micron) and low-copy (CEN/ARS) reporter plasmids, compared to about 3-fold for GPD under the same comparison.
Applications: Constitutive expression of heterologous genes, selection markers, and reporter constructs in S. cerevisiae at a lower output level than TEF1 or GPD, useful when more moderate expression is preferred or when copy-number-dependent tuning of expression is desired. Widely used in standard yeast expression and metabolic engineering vectors.
Limitations: Produces substantially lower expression than TEF1 or GPD/TDH3 promoters in side-by-side comparisons, and output varies more with plasmid copy number, which can complicate reproducibility between centromeric and multicopy constructs. Constitutive activity cannot be induced or repressed on demand.