The region of CQQQKPQRRP of PGC-1alpha interacts with the DNA-binding complex of FXR/RXRalpha.
PGC-1alpha co-activates transcription by several nuclear receptors. To study the interaction among PGC-1alpha, RXRalpha/FXR, and DNA, we performed electrophoresis mobility shift assays. The RXRalpha/FXR proteins specifically bound to DNA containing the IR-1 sequence in the absence of ligand. When the fusion protein of GST-PGC-1alpha was added to the mixture of RXRalpha/FXR/DNA, the ligand-influenced retardation of the mobility was observed. The ligand for RXRalpha (9-cis-retinoic acid) was necessary for this retardation, whereas, the ligand for FXR, chenodeoxycholic acid, barely had an effect. The results obtained using truncated PGC-1alpha proteins suggested that two regions are necessary for PGC-1alpha to interact with the DNA-binding complex of RXRalpha/FXR. One is the region of the second leucine-rich motif, and the other is that of the amino acid sequence CQQQKPQRRP, present between the second and third leucine-rich motifs. The results obtained with the SPQSS mutation for KPQRR suggested that the basic amino acids are important for the interaction.
Kanaya
Eiko
E
Department of Molecular Biology, Biomolecular Engineering Research Institute (BERI), Osaka, Japan.
Jingami
Hisato
H
D000595:Amino Acid Sequence; D001667:Binding, Competitive; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D006360:Heat-Shock Proteins / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D010455:Peptides / Q000378:metabolism*; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D011485:Protein Binding; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification / Q000378:metabolism; D047490:Retinoid X Receptor alpha / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D000099150:Receptor, Farnesoid X-Activated
D004247:DNA; D004268:DNA-Binding Proteins; D006360:Heat-Shock Proteins; D010455:Peptides; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins; D047490:Retinoid X Receptor alpha; D014157:Transcription Factors; D000099150:Receptor, Farnesoid X-Activated; C486497:PPARGC1A protein, human