Immunoblotting Analysis of Cellular Proteins

The protein of cells was extracted for immunoblotting as described previously [18 (link),19 (link),20 (link)]. Briefly, the cells were harvested with lysis buffer containing protease inhibitor cocktail. The proteins were separated by SDS-PAGE and transferred to nitrocellulose membranes for further immunoblotting with the primary antibodies, including anti-DYRK1B (1:1000, 5672, Cell Signaling Technology), anti-His tag (1:1000, 12698, Cell Signaling Technology), and anti-ACTB (1:2000, A5441, Sigma) at 4 °C overnight, followed by probing with secondary antibody and ECL reagent. The membrane was scanned and analyzed for protein expression as uncropped images in Figure S1 with a BioSpectrum^® Imaging System (UVP, Upland, CA, USA).