FIG. 5.

Role of LXXLL motif in the binding of SRC-1 to AhR and ER transactivation domains. SRC-1a or SRC-1a mut, in which all the LXXLL motifs were mutated, were in vitro transcribed and translated in the presence of [³⁵S]methionine and incubated in the presence of CSB buffer with either GST, GST-mAhRTAD or GST-ER-HBD immobilized on 30 μl of glutathione agarose. Following a 1.5-h incubation, the agarose was washed with CHAPS buffer. The bound proteins were eluted with 2× TSB and subjected to SDS-PAGE and visualized by fluorography. 1/10 input represents 1/10th of the amount of [³⁵S]methionine-labeled SRC-1 used in the binding reactions.