Immunofluorescence Staining of Transfected Cells

IF staining was performed as previously described [28 (link)]. In brief, cells were cultured and seeded in small confocal dishes with 5 × 10⁴ cells/dish. After transfection with plasmids for 48 h or EGCG (an agonist of cytoplasmic YAP1 localization) treatment for 6 h, cells were fixed with 4% paraformaldehyde (BL539A, Biosharp Life Sciences, Beijing, China), permeabilized with 0.5% PBS‐Triton X‐100, and blocked with 10% goat serum (AR0009, Boster). Cells were incubated with primary antibody overnight at 4°C, then incubated with the corresponding secondary antibody (Dylight 488/594 Goat Anti‐Mouse/Rabbit IgG, A23210/A23320, Abbkine, Wuhan, Hubei, China) for 1 h at 25°C in the dark the following day. Nuclei were stained with 4',6‐diamidino‐2‐phenylindole (DAPI, AR1176, Boster), after which anti‐fluorescence quenching mounting medium (AR0036, Boster) was added. Cells were then imaged with Zeiss LSM 800 Confocal Laser Scanning Microcopy (Carl Zeiss AG, Oberkochen, Germany).