Aminoacylase expression is up-regulated upon neuronal differentiation of SK-N-SH cells
SK-N-SH cells were arrested by growth in media containing 1% FBS for 12 hours prior to neuronal induction with cAMP. Cells were grown in the absence (A–C) or presence of cAMP (D–F) for 7 days and examined immunocytochemically. Expression of both ACY1 (A, D) and ACY3 (C, F) were robustly expressed in differentiated neurons, as revealed by prominent neurite outgrowth (D′, F′). ASPA was expressed in cells with Schwannian morphology (B, B′), but not in arrested cells with neurite-like processes (B, B′ arrows). In contrast, ASPA was expressed in neurons (E, E′ arrows), particularly at points of cell-cell contact (E, E′ arrowheads), in response to cAMP treatment. Scale bar = 100 μm, inset = 50 μm.