Immunofluorescence staining was performed as previously reported17 (link).Briefly, cultured cells on glass coverslips or frozen tissue sections (8 μM thickness) were fixed in 4% paraformaldehyde for 10 min and blocked with blocking buffer (0.1% Triton X-100 and 10% normal serum in PBS) for 1 h. Fixed cells or tissue sections were then incubated with the indicated primary antibodies for 2 h followed by fluorochrome-conjugated secondary antibodies. After being washed with PBS, the slides were incubated with DAPI (Sigma) for nuclear staining. Images were acquired with a fluorescence confocal microscope (Zeiss, Thornwood, NY, USA).