Figure 6.

The distinct signaling mechanisms of the p75 neurotrophin receptor and its co-receptors. When p75NTR interacts with TRK-receptors (A, B, C), mature neurotrophins (NGF, BDNF, NT3, and NT4) serve as ligands. The effects of these interactions are primarily neuroprotective. However, when interacting with sortilin, the affinity for pro-neurotrophins increases, leading primarily to neurodegenerative effects. p75NTR = p75 neurotrophin receptor; TRK = receptor tyrosine kinase; NGF = neuro growth factor; BDNF = brain-derived neurotrophic factor; NT3 = neurotrophin-3; NT4 = neurotrophin-4.