NTF3-bound NTRK2 dimers trans-autophosphorylate

NTF3-induced dimerization of the receptor tyrosine kinase NTRK2 (TRKB) leads to trans-autophosphorylation of NTRK2 on evolutionarily conserved tyrosine residues in the cytoplasmic tail of NTRK2. Phosphorylation of NTRK2 at Y817 and in the region containing residues Y702, Y706 and Y707 in response to NTF3 stimulation was demonstrated with recombinant human NTF3 and recombinant rat Ntrk2. Residues Y702, Y706, Y707 and Y817 of the full-length human NTRK2 correspond to residues Y670, Y674, Y675 and Y785 of the mature rat Ntrk2 (Middlemas et al. 1994). Phosphorylation at Y516 of NTRK2 has not been examined but is assumed. NTRK2 is a low affinity receptor for NTF3, and NTF3 preferentially signals through NTRK3 (TRKC) (Marsh and Palfrey 1996).

NTF3诱导的受体酪氨酸激酶NTRK2（TRKB）的二聚化导致NTRK2在细胞质尾部进化上保守的酪氨酸残基处发生自磷酸化。通过重组人源NTF3和重组大鼠Ntrk2，证实了NTRK2在Y817位点和响应NTF3刺激时含有Y702、Y706和Y707残基的区域发生磷酸化。全长人源NTRK2中的Y702、Y706、Y707和Y817残基分别对应成熟大鼠Ntrk2（Middlemas等，1994）中的Y670、Y674、Y675和Y785残基。NTRK2对NTF3的亲和力较低，且NTF3优先通过NTRK3（TRKC）信号（Marsh和Palfrey，1996）。