ASSIGNMENT OF DISULFIDE BONDS IN CORTICOTROPIN-RELEASING FACTOR-BINDING PROTEIN

We have previously isolated, cloned, and characterized a protein that specifically binds and inactivates the peptide corticotropin-releasing factor. The integrity of the disulfide bonds in the binding protein i s essential for this activity as reduction abolishes the protein's abi lity to bind corticotropin-releasing factor. The disulfide arrangement of the 10 cysteines present in the mature protein was established by analysis of proteolytically cleaved protein and sequence analysis of c ystine containing fragments. A pattern is observed where each cysteine is connected to the next one in a sequential manner. Inspection of th e genomic DNA encoding for this protein reveals that four of the domai ns defined by disulfide linkage coincide with four different exons.