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Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We demonstrate that the hormone-binding domain (HBD) of the human estrogen receptor (ER) can function as an autonomous regulatory domain in the budding yeast, Saccharomyces cerevisiae. As in mammalian cells, the HBD can subject the activity of a heterologous protein, which is fused to it, to hormonal control. Thus, a chimeric transcriptional activator consisting of (i) the DNA-binding domain of GAL4, (ii) the ER HBD, and (iii) the activation domain of viral protein 16 (VP16) stimulates both episomal and integrated reporter genes exclusively in the presence of steroid hormone. Steroids being gratuitous signals for yeast, this fusion protein is a convenient tool for highly regulated production of proteins of interest. Notably, it can be exploited to activate the commonly used galactose-inducible expression vectors without switching the carbon source.
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PMID:Fusion of GAL4-VP16 to a steroid-binding domain provides a tool for gratuitous induction of galactose-responsive genes in yeast. 837 May 33

This report describes a novel yeast one-hybrid system which easily allows for the detection of mutations in the ligand-binding domain of the estrogen receptor. This screen is based on the observation that a fusion protein consisting of the GAL4 DNA-binding domain and the estrogen receptor can interact with a GAL4 upstream activating sequence and induce the expression of an integrated GAL1-lacZ gene only in the presence of estradiol. Various deletion mutants of the estrogen receptor were tested in this assay and activating function 1 which is present in the N-terminus of the estrogen receptor was found to be responsible for the transactivation produced in the assay. To test if the screen could be used to detect random mutants in the ligand-binding domain of the estrogen receptor the region of the human receptor between amino acids 381 to 403 was mutated by oligonucleotide saturation mutagenesis. Two of the mutants generated by this mutagenesis were characterized to demonstrate that the results obtained from the screen in the yeast screen are relevant to mammalian systems. One of the mutants which has a valine at position number 388 instead of a glycine was able to transactivate in both the yeast and a mammalian system. This mutant was a more potent activator of transcription and also appeared to have a higher affinity for [3H]estradiol in vivo than the wild type receptor. The other mutant which was characterized has five amino acid changes from amino acids 390 through 400. This mutant was nonfunctional in the yeast and mammalian transcription assays and did not bind [3H]estradiol in vivo or in vitro.
Steroids 1996 Mar
PMID:Use of the yeast one-hybrid system to screen for mutations in the ligand-binding domain of the estrogen receptor. 885 26

We investigated the evolution of the response of human, chicken, alligator and frog glucocorticoid receptors (GRs) to dexamethasone, cortisol, cortisone, corticosterone, 11-deoxycorticosterone, 11-deoxycortisol and aldosterone. We find significant differences among these vertebrates in the transcriptional activation of their full length GRs by these steroids, indicating that there were changes in the specificity of the GR for steroids during the evolution of terrestrial vertebrates. To begin to study the role of interactions between different domains on the GR in steroid sensitivity and specificity for terrestrial GRs, we investigated transcriptional activation of truncated GRs containing their hinge domain and ligand binding domain (LBD) fused to a GAL4 DNA binding domain (GAL4-DBD). Compared to corresponding full length GRs, transcriptional activation of GAL4-DBD_GR-hinge/LBD constructs required higher steroid concentrations and displayed altered steroid specificity, indicating that interactions between the hinge/LBD and other domains are important in glucocorticoid activation of these terrestrial GRs.
Steroids 2016 09
PMID:Evolution of corticosteroid specificity for human, chicken, alligator and frog glucocorticoid receptors. 2731 37