Our present findings from genetic manipulation suggest that CRMP3 has critical roles both in the axon and dendrite morphogenesis of neurons in DG and CA1, and position the protein as an important intracytoplasmic determinant of hippocampal neuronal structure and, consequently a modulator of the hippocampal trisynaptic circuitry function implicated in chronic stress and depression [36], schizophrenia [37], age-associated neurodegeneration, and memory loss [38]. The gene discussed is DPYSL4; the disease is major depressive disorder.