We previously demonstrated that the 1alpha,25-dihydroxyvitamin D(3) receptor (VDR) interacts with the constitutive heat shock protein, hsc70 in vitro, and with DnaK (Biochem. Biophys. Res. Commun. 260, 446-452, 1999). The biological significance of VDR-heat shock protein interactions, however, is unknown. To examine the role of such interactions in eukaryotic cells, we heterologously expressed VDR and RXRalpha together with a vitamin D-responsive reporter system in Saccharomyces cerevisiae and examined the consequences of heat shock protein 70 gene (SSA) deletion in these cells. We show that heterologously expressed VDR associates with the yeast cytosolic hsp70 protein, Ssa1p. Deletion of the SSA2, SSA3, and SSA4 genes and reduction of Ssa1p activity, reduces the intracellular concentrations of the VDR and its heterodimeric partner, RXRalpha and reduces the activity of a vitamin D-dependent gene. Hsp70-like chaperone proteins play a role in controlling concentrations of the VDR within the cell. Copyright 2001 Academic Press.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Annotation Extension||Reference|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Assay||Construct||Conditions||Strain Background||Reference|