Figure 8. LRRK2 overexpression counteracts the neural protective effect of shSp1. SH-SY5Y and PC-12 cells were treated with 1 mM MPP+ and transfected with shNC, shSp1 or the LRRK2 overexpression vector. (A) The expressions of Sp1 and LRRK2 at the mRNA level were determined by qPCR analysis. (B) The expressions of Sp1, LRRK2 and α-synuclein at protein level were determined by western blot analysis. (C) Flow cytometry analysis of apoptosis was performed. (D) Apoptotic cells in different groups were compared. (E) TUNEL staining was performed to assess SH-SY5Y and PC-12 cell apoptosis under the indicated conditions. (F) Cell proliferation was determined by the CCK-8 assay. (G) MES23.5 cells were transfected with shNC, shSp1 or LRRK2 overexpression vector and treated with 1 mM MPP+. The localization of TUBB3 in MES23.5 cells is shown in the representative images. (H) Cell cycle phases were determined by propidium iodide staining and flow cytometry. (I) Comparison of cell cycle of SH-SY5Y and PC-12 cells in the different groups. The data are representative of three experiments. *p <0.05, **p <0.01 and ***p <0.001.