The present invention relates to a ligand of the Corticotropin-Releasing Factor (CRF)-binding protein (CRFBP) selected from the group consisting of CRF, Urocortin (Ucn), and Urotensin, said ligand comprising a covalently linked benzophenone moiety. Further, the present invention relates to a process for the purification of a CRFBP which comprises reacting said CRFBP with the ligand of the invention, performing photoaffinity labeling, and purifying the resultant photoreaction products by HPLC. The present inventio n also relates to the use of the ligand of the invention for detecting CRFBP a nd for identifying the binding site within CRFBP. The present invention also relates to a method for identifying an inhibitor of the binding of ARF to CRFBP.
BENZOPHENONE-LINKED CRF AND CRF-LIKE PEPTIDES FOR COVALENT LABELING OF CORTICOTROPIN-RELEASING FACTOR (CRF) BINDING PROTEIN