Immunoblotting
Aliquots of total protein (30 μg) were loaded on 4%–12% SDS-polyacrylamide gels (NuPAGE 4%–12% Bis-Tris Protein Gels, ThermoFisher Scientific), transferred to a PVDF membrane with an iBlot2 PVDF Mini transfer stack (ThermoFisher Scientific), and subsequently probed with a polyclonal antibody recognizing EXOSC8 (Proteintech, 1:500), EXOSC3 (Proteintech, 1:1,000), EXOSC9 (Abcam ab156686, 1:1,000), RBM7 (Abcam ab84116, 1:500), β-actin (Sigma A1978, 1:2,000), and α-tubulin (Invitrogen A11126, 1:2,000).