Saccharomyces cerevisiae alcohol dehydrogenase 1 (ADH1) promoter, short truncation
A 397 bp 5' truncation of the S. cerevisiae ADH1 promoter, the constitutive promoter of the fermentative alcohol dehydrogenase gene. The most compact of the ADH1 promoter fragments in this corpus, retaining the core promoter region closest to the ADH1 start codon while removing most of the upstream sequence present in the full-length 1452 bp promoter (adh1-long).
Origin: Saccharomyces cerevisiae, minimal ADH1 upstream region
Characteristics
Contains only the ADH1 core promoter and transcription start site region, removing more than 1000 bp of upstream sequence present in the full-length 1452 bp promoter, including the region carrying its UAS elements. ADH1-driven constitutive expression is markedly copy-number-dependent (about 30-fold higher activity on a 2-micron plasmid than on a CEN/ARS plasmid, versus about 3-fold for GPD), so absolute output from this fragment depends heavily on plasmid backbone.
Applications: Constitutive expression of heterologous genes, selection markers, and reporter constructs in S. cerevisiae where the most compact ADH1 promoter fragment is needed, e.g., for size-constrained cloning or synthetic constructs assembled from short standard parts.
Limitations: Removes most of the upstream activating sequence present in the full-length adh1-long promoter and is expected to give lower output than the full-length or medium-length forms, but this specific truncation's activity has not been directly measured in the cited literature. Constitutive activity cannot be induced or repressed on demand.