Cell Culture and Viral Transduction

SH-SY5Y cells were purchased from ATCC and cultured in 50% Minimum Essential Medium (MEM) and 50% F-12 with 10% fetal bovine serum. Cell counts were performed using Trypan blue exclusion and a Countess II automated cell counter (Life Technologies). For viral transduction, HEK293T cells were transfected with either non-targeting shRNA (NTsh; control) or DEK-targeting shRNA (DEKsh; pLKO.1_DEK832; #TRCN0000013104) plasmid DNA in the pLKO.1 plasmid backbone (Sigma–Aldrich MISSION shRNA), as previously published (Privette Vinnedge et al., 2011). The virus was collected from HEK293T cells 48–72 h later, filtered with a 0.45-micron syringe filter, and added to SH-SY5Y cells overnight with polybrene. The selection for transduced cells was completed using puromycin (2.0 μg/ml) for 72 h.