Activated NTRK2 signals through FRS2 and FRS3

Adapter proteins FRS2 and FRS3 can both bind to the cytoplasmic tail of activated NTRK2 (TRKB) receptor, which is followed by NTRK2-mediated phosphorylation of FRS2 and FRS3. NTRK2 signaling through FRS3 has been poorly characterized (Easton et al. 1999, Yuen and Mobley 1999, Dixon et al. 2006, Zeng et al. 2014). Phosphorylated FRS2 is known to recruit GRB2 (presumably in complex with SOS1) and PTPN11 (SHP2) to activated NTRK2, leading to augmentation of RAS signaling (Easton et al. 1999, Easton 2006).

适配蛋白FRS2和FRS3均能结合激活的NTRK2（TRKB）受体的胞浆尾端，随后引发NTRK2介导的FRS2和FRS3的磷酸化。NTRK2通过FRS3的信号传导机制尚不明确（Easton等，1999年，Yuen和Mobley，1999年，Dixon等，2006年，Zeng等，2014年）。已知磷酸化的FRS2能够募集GRB2（可能伴随SOS1复合物）以及PTPN11（SHP2）至激活的NTRK2，从而增强RAS信号传导（Easton等，1999年，Easton，2006年）。