Serine Phosphorylation-dependent Association of the Band 4.1-related Protein-tyrosine Phosphatase PTPH1 with 14-3-3β Protein

摘要: PTPH1 is a human protein-tyrosine phosphatase with homology to the band 4.1 superfamily of cytoskeletal-associated proteins. was found associate 14-3-3 using yeast two-hybrid screen, and its interaction could be reconstituted in vitro recombinant Examination between various deletion mutants by tests suggested that integrity PTP important for this binding. Although both Raf-1 form complexes 14-3-3, they appear do so independently. Binding PTPH1in abolished pretreating potato acid greatly enhanced Cdc25C-associated protein kinase. Thus association phosphorylation-dependent. Two novel motifs RSLS359VE RVDS853EP were identified as major 14-3-3-binding sites, which are distinct from consensus binding motif RSXSXP recently Raf-1. Mutation Ser359 Ser853 alanine significantly reduced PTPH1. Furthermore, detected several cell lines regulated response extracellular signals. These results raise possibility may function an adaptor molecule regulation provide link serine/threonine tyrosine phosphorylation-dependent signaling pathways.