Analysis of trk A and p53 association

trk A tyrosine kinase (the high affinity receptor for nerve growth factor) binds to the p53 tumour suppressor protein in vitro and in vivo. Our aim wa s to determine which regions of p53 are involved in trk A association. In v itro binding experiments using baculovirus expressed trk A and in vitro tra nscribed and translated C-terminus p53 deletion mutants show amino acids 32 7-338 critical for association. Also, analysis with mutants at the N-termin us, conserved regions II, III, IV and V or amino acid positions 173, 175, 1 81, 248 and 249 (which are amino acids frequently mutated in a variety of n eoplasms and transformed cell lines). show that these sites are not involve d in trk A binding. Importantly. similar results are obtained after immunop recipitation of lysates from p53 negative fibroblasts expressing trk A and the above p53 mutant proteins. These data suggest that the amino-terminus o f the oligomerisation domain of p53 is involved in p53/trk A association. ( C) 2001 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.