Finally, the mature stage T5 was enriched for synaptic signaling genes (FDR = 5 × 10–16; e.g., CADPS2 and SNAP25) and regulation of membrane potential (FDR = 3 × 10–11; e.g., RIMS1 and SCN2A), and was most specifically marked by RBFOX1, an RNA-binding protein implicated in many mental disorders. Here, RBFOX1 is linked to psychiatric disorder.