Study Of The Interaction Between The Neurotrophin Receptor Trka, P75 Ntr And Ranbpm And Other Protein

Neurotrophins can affect most of the function of vertebrate nervous system. They exert individual cellular effects through binding to the two structurally different receptors, the Trk (tropomyosin-related kinase) receptor tyrosine kinase and the p75 neurotrophin receptor (p75NTR). TrkA receptor belongs to the receptor protein tyrosine kinase, when phosphorylated it can activate signal proteins through recruitment of proteins to its tyrosine residues in an active complex .The tyrosine kinase Met is the receptor for hepatocyte growth factor (HGF), which tyrosine kinase domain shares about 37% amino acid sequence identity with that of the receptor TrkA. Met has been show to integrate with RanBPM, consequently cause constitutive activation of the Ras signaling pathway. So, we speculate TrkA receptor could interact with RanBPM. In this study we found: l.TrkAICD could interact with RanBPM and the interaction was confirmed by yeasttwo-hybrid assays, GST pull-down assays and co-immunoprecipitaiton studies, andFRET assays. 2.TrkAICD-RanBPM association through SPRY domain of RanBPM was confirmed byyeast two-hybrid assays and co-immunoprecipitaiton studies. 3.The region of TrkA interacted with the SPRY domain of RanBPM was located in thetyrosine kinase domain by yeast two-hybrid assays.It was reported that TrkAICD and p75NTRICD could not interacted in transfected mammalian cells. So it is important to know whether RanBPM links TrkA and p75NTR simultaneously as a bridging protein and then to transduct the extracellular signal. In this research, we found:1. RanBPM could coupled TrkAICD and p75NTRICD and form a triploid complex.2. There were other protein such as Heat shock protein 70, 90, P-actin and eIF4A in the immunocomplex.