A novel cytoplasmic protein that interacts with the Ah receptor, contains tetratricopeptide repeat motifs, and augments the transcriptional response to 2,3,7,8-tetrachlorodibenzo-p-dioxin.
To identify new proteins involved in dioxin-dependent signal transduction and transcriptional regulation, we used a yeast two-hybrid system to identify proteins that interact with the Ah receptor ( AhR). We cloned a mouse cDNA, which encodes a novel approximately 37-kDa protein that binds to AhR; we have designated the protein as Ah receptor-interacting protein ( AIP). The amino acid sequence of mouse AIP exhibits homology with members of the FK506-binding protein family. AIP also contains three tetratricopeptide repeat ( TPR) motifs; the TPR sequence is present in proteins required for cell cycle control and RNA synthesis and in steroid receptor-binding immunophilins. Coimmunoprecipitation experiments in mouse hepatoma cells reveal that AIP is cytoplasmic and associates with unliganded Ah receptor and with hsp90; 2,3,7,8-tetrachlorodibenzo-p-dioxin treatment disrupts the AhR- AIP- hsp90 interaction. Overexpression of AIP augments the response of the CYP1A1 gene to 2,3,7,8-tetrachlorodibenzo-p-dioxin. Our data suggest that AIP influences ligand receptivity and/or nuclear targeting of AhR.[1]References
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg