We have previously shown that protein-protein interactions mediate cooperative binding of the glucocorticoid receptor DNA-binding domain to a response element (Dahlman-Wright, K., Siltala-Roos, H., Carlstedt-Duke, J., and Gustafsson, J.-A. (1990) J. Biol. Chem. 265, 14030-14035). The cooperativity DNA is lost when distance between two half-sites constituting responsive altered or their relative orientation changed. show here mutations in which interfere with by vitro also abolish...

The so-called thioredoxin system, (Trx), reductase (Trr), and NADPH, acts as a disulfide system can protect cells against oxidative stress. InSaccharomyces cerevisiae, two thioredoxins (Trx1 Trx2) one (Trr1) have been characterized, all of them located in the cytoplasm. We identified characterized novel S. cerevisiae. TheTRX3 gene codes for 14-kDa protein containing characteristic active site (WCGPC). TRR2gene 37 kDa with active-site motif (CAVC) present prokaryotic reductases binding sites...

It is well established that differences in migratory behavior between populations of songbirds have a genetic basis but the actual genes underlying these traits remains largely unknown. In an attempt to identify such candidate we de novo assembled genome willow warbler Phylloscopus trochilus, and used whole-genome resequencing SNP array associate genomic variation with phenotypes across two divides around Baltic Sea separate SW migrating P. t. trochilus wintering western Africa SSE acredula...

A 58-amino acid polypeptide containing the functional core region, tau 1 core, of major transactivation domain human glucocorticoid receptor has been expressed in Escherichia coli and purified to homogeneity. The retains 60-70% activity intact when assayed vivo or vitro. This report describes a structural characterization peptide fragment. Circular dichroism spectroscopy shows that larger fragment encompassing are largely unstructured water solution under variety pH conditions. however,...

RNA interference is a form of gene silencing in which the nuclease Dicer cleaves double-stranded into small interfering RNAs. Here we report role for chromosome segregation fission yeast. Deletion ( dcr1 + ) caused slow growth, sensitivity to thiabendazole, lagging chromosomes during anaphase, and abrogated centromeric repeats. As other species, Dcr1p degraded ≈23 nucleotide fragments vitro , Δ cells were partially rescued by expression human Dicer, indicating evolutionarily conserved...

The N-terminal regions of the estrogen receptor α (ERα-N) and β (ERβ-N) were expressed purified to homogeneity. Using NMR circular dichroism spectroscopy, we conclude that both ERα-N ERβ-N are unstructured in solution. TATA box-binding protein (TBP) has been shown previously interact with <i>in vitro</i> potentiate ER-activated transcription. We used surface plasmon resonance spectroscopy confirm further characterize ER-N-TBP interaction. Our results show intrinsically interacts TBP, suggest...

Cellular levels of the rapidly degraded c-myc protein play an important role in determining proliferation status cells. Increased are frequently associated with proliferating tumor We show here that myc boxes I and II, found N termini all members family, function to direct degradation protein. Both II contain sufficient information independently otherwise stably expressed proteins which they fused. At least part box-directed occurs via proteasome. The mechanism appears be conserved between...

The SWI-SNF complex has been shown to alter nucleosome conformation in an ATP-dependent manner, leading increased accessibility of nucleosomal DNA transcription factors. In this study, we show that the can potentiate activity glucocorticoid receptor (GR) through N-terminal transactivation domain, τ1, both yeast and mammalian cells. GR-τ1 directly interact with purified complex, mutations τ1 affect vivo also interaction SWI-SNF. Furthermore, stimulate τ1-driven from chromatin templates vitro....

c-Myc is a member of family sequence specific-DNA binding proteins that are thought to regulate the transcription genes involved in normal cell growth, differentiation, and apoptosis. In order understand how human c-myc functions as factor, we have studied mechanism action structure N-terminal transactivation domain, amino acids 1-143. protein interaction assay, c-myc1-143 bound selectively two basal factors, TATA (TBP) RAP74 subunit TFIIF. Furthermore, isolated domain competed for limiting...

To investigate the role of acidic and phosphorylated amino acids in function major transactivation domain (τ1) glucocorticoid receptor, we have performed a mutagenesis study. Aspartic glutamic acid residues were neutralized clusters 2 to 4 throughout τ1 domain. The activity mutant proteins was determined using assays yeast mammalian cells. Some core region appear play minor activity, but, generally, individual are not critical for activity. Mutagenesis five serine that mouse receptor which...

Previous deletion analysis localized the major transactivation function of human glucocorticoid receptor to a 185-amino acid segment close N terminus protein. This region was named tau 1 [Hollenberg, S. M. &amp; Evans, R. (1988) Cell 55, 899-906]. To delineate smallest active within 1, we have systematically tested capacity derivatives domain, fused DNA-binding in yeast cells. Internal scanning deletions suggested that residues near C are most important for activity. Deletions N-terminal and...

A refined solution structure of the glucocorticoid receptor DNA-binding domain (GR DBD) has been determined using two- and three-dimensional nuclear magnetic resonance (NMR) spectroscopy on an 15N-labeled GR DBD fragment in conjunction with distance geometry simulated annealing calculations. Thirty structures C440-R510 rat were calculated based 906 constraints obtained from NOE intensities (168 intraresidue 738 interresidue NOEs) 43 dihedral constraints. Average atomic root mean square (rms)...

Abstract Background Understanding the adaptive changes that alter function of proteins during evolution is an important question for biology and medicine. The increasing number completely sequenced genomes from closely related organisms, as well individuals within species, facilitates systematic detection recent selection events by means comparative genomics. Results We have used genome-wide strain-specific single nucleotide polymorphism data 64 strains budding yeast ( Saccharomyces...

// Yichun Qiao 1 , Chiou-Nan Shiue 2, 3 Jian Zhu Ting Zhuang Philip Jonsson 4 Anthony P.H. Wright 2 Chunyan Zhao Karin Dahlman-Wright 1, 5 Department of Biosciences and Nutrition, Novum, Karolinska Institutet, Huddinge, Sweden Clinical Research Center (KFC), Laboratory Medicine, Pediatrics, Hualien Tzu Chi Hospital, Buddist Medical Foundation, Hualien, Taiwan for Nuclear Receptors Cell Signaling, Biology Biochemistry, University Houston, USA Science Life Laboratory, Solna, Correspondence to:...

The glucocorticoid receptor (GR) is a ligand-activated transcription factor. In this study, we used the yeast two-hybrid system to isolate cDNAs encoding proteins that interact with human GR ligand-binding domain (LBD) in ligand-dependent manner. One isolated cDNA from HeLa cell library encoded COOH-terminal portion of η-isoform 14-3-3 protein (residues 187–246). Glucocorticoid agonists, triamcinolone acetonide and dexamethasone, induced LBD/14-3-3η fragment interaction, but an antagonist,...

c-Myc is a predominately nuclear transcription factor that substrate for rapid turnover by the proteasome system. Cancer-related mutations in lead to defects its degradation and thereby contribute increase cellular level associated with disease. Little known about mechanisms target proteasomes. By using GFP fusion protein live analysis we show shuttles between nucleus cytoplasm thus it could be degraded either compartment. Strikingly, at elevated levels of expression accumulates nucleoli...

HeLa cell nuclear extracts were used to study the mechanism of activation RNA polymerase II-mediated transcription by N-terminal transactivation domain (tau1) glucocorticoid receptor in vitro. When fused Gal4 DNA-binding domain, tau1 activated approximately 9-fold extracts. Using heat treatment inactivate factor IID (TFIID) extract, it was shown that addition purified TFIID complex, but not TATA-binding protein alone, sufficient restore this level activation. The interact directly with...

In this study we have reconstituted transactivation of gene expression by the human glucocorticoid receptor in yeast, Saccharomyces cerevisiae. We expressed C-terminal half (residues 415-777), smallest derivative that can be expected to function as a ligand-dependent activator transcription, yeast cells. The protein has been assayed using reporter consisting beta-galactosidase from Escherichia coli fused iso-1-cytochrome c promoter with glucocorticoid-responsive element rat tyrosine...