Yeast genes involved in thiamin pyrophosphate (TPP) synthesis are transcriptionally induced in response to thiamin starvation. In this system, three proteins (Thi2p, Thi3p, and Pdc2p) act as positive regulatory factors. Thi3p is a TPP-binding protein and upregulates THI genes expression when TPP is not bound. We found here that Pdc2p could transactivate gene expression and interact with Thi3p, both of which were enhanced by thiamin starvation. This enhancement of the transactivation activity was not observed in a thi3 strain. When the C-terminal region containing the deduced Thi3p-interacting domain was truncated, Pdc2p expressed striking transactivation activity in a Thi3p-independent fashion. We explored the hypothesis that Thi3p causes a conformational change in Pdc2p leading to full transactivation activity under favorable conditions. STRUCTURED SUMMARY:.
|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||Reference||Annotation Extension|
|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||Conditions||Strain||Source||Reference|