Fig. 2.

NTF signaling through Trk receptors. This diagram shows the main intracellular signaling axes associated with each neurotrophin receptor. Each Trk receptor isoform connects to a mature NTF and performs through three predominant pathways, including Ras/MEK/ERK, PLC-γ1/PKC, and PI3K/Akt. TrkA, TrkB, and TrkC, tropomyosin receptor kinases; NTFs, neurotrophic factors; mek, mitogen-activated protein kinase; ERK, extracellular-signal-regulated kinase; PLCγ1, phospholipase C gamma 1; PI3K, phosphatidylinositol 3-kinase; PKC, protein kinase C; NFATC, nuclear factor of activated T cells, cytoplasmic 1; CREB, cAMP response element-binding protein; mTOR, mechanistic target of rapamycin; PIP2, phosphatidylinositol 4,5-bisphosphate