Molecular Interaction Between PrP Protein And The Signal Protein 14-3-3β

Objective: Prion diseases are rare degenerative neurological disorders. Prion protein is the Pathogenicity factor and it has a self- replication capacity. The prion protein mainly exists in the brain with the toxic-bit region in 106-126 amino acids. 14-3-3βprotein is an ubiquitous protein in mammalian mainly in the brain, with the function in signal transduction and protection. To study interaction between normal prion protein and 14-3-3βand identify the region in Prion protein , we study the possible mechanisms of 14-3-3βprotein in the Creutzfeldt -Jakob disease.Methods: Firstly We expressed the prion proteins and 14-3-3βprotein; secondly, we studied the molecular interaction between PrP and 14-3-3βby co-immunoprecipitation, pull down and FRET assays as well as the possible interactional domain between the two proteins.Results: Firstly, we used a group of recombinant prion proteins (contained 106-126 amino acid) and recombinant 14-3-3βprotein by immunoprecipitation experiments and pull down experiments; Secondly, we studied the interaction between recombinant prion proteins and natural 14-3-3βprotein ,and between natural prion proteins and recombine 14-3-3βproteins by pull down experiments; then we studied the interaction between natural prion proteins and14-3-3βprotein by immunoprecipitation experiments. Last, in order to detect the interaction region in prion protein, we used another group of recombinant prion proteins (no 106-126 amino acids) and 14-3-3βprotein by immunoprecipitation experiments. In order to study the interaction between prion protein and14-3-3 protein in cell, we expressed the no-signal peptide as PrP23-231, and transfected into HeLa cells. So the prion protein expressed in the cytoplasm like 14-3-3 protein, incubated with two first-antibody, and then incubated by adding FITC labeled anti-mouse antibody and labeled anti-rabbit rodamine antibody, observed by microscope in the further processing.Conclusions: The interaction exists between the prion protein and 14-3-3βprotein in vitro and in cells. The interaction domain is in the region of 106-126 amino acid in prion protein. The toxicity region of prion protein is in 106-126 amino acid, and 14-3-3βprotein maybe play a role in regulating prion protein to inhibit prion replication.