Effect of HDAC6 inhibition on membrane localization of β-catenin.
(A, B) Immunofluorescence staining for β-catenin treated with
HDAC6 inhibitor (A) and HDAC6 siRNA (B) in human NPCs. Cells were
treated with 5 μM ACY-1215 or DMSO for 18 h (A) or with HDAC6
siRNA and control siRNA for 72 h (B) and imaged with anti-β-catenin
antibody (green), anti-β-tubulin antibody (red), and Hoechst
33342 (blue). Scale bar, 20 μm. Quantification of β-catenin
levels at the membrane represent two independent experiments with
three fields of view each at 20× magnification. Error bars indicate
standard deviation. ** and **** denote significance at p < 0.01 and p < 0.0001, respectively (unpaired t test). (C) Immunoblot analysis for nuclear (N) and membrane/cytoplasmic
(M/C) fractions for NPCs treated with HDAC6 inhibitor ACY-1215 (5
μM) or DMSO for 6 h. Histone H3 is shown as a nuclear marker,
GAPDH as a cytoplasmic marker and integrin β1 as a membrane
marker. (D) Immunoblot analysis for Ac-Lys49-β-catenin bound
to N-cadherin. Human NPCs were treated with ACY-1215 (5 μM)
or DMSO for 24 h, lysates immunoprecipitated with anti-N-cadherin
antibody and immunoblotted with antibodies against β-catenin
and Ac-Lys49-β-catenin.