Fig. 3.

Mechanical loading blocks IL-1β induced tubulin acetylation and reduces non-polymerized tubulin expression via activation of HDAC6. (A) Representative confocal immunofluorescence for acetylated-α-tubulin (Acet-α-Tub, red), HDAC6 (green) in cultured chondrocytes showing co-localization on the cilia axoneme. (B) HDAC6 activity for cells ± IL-1β (1 ng/ml) in the presence or absence of cyclic tensile strain (CTS, 0–10%, 0.33 Hz, 24 h, n = 6, N = 2). Western blot analysis of tubulin based on (C–D) total protein levels and (E–F) non-polymerized protein for cells ± IL-1β (1 ng/ml) in the presence or absence of cyclic tensile strain (CTS) as above. (C and E) Representative blots and corresponding semi-quantitative analysis of (D) ratio of acetylated-α-tubulin to α-tubulin and (F) non-polymerized α-tubulin expression (n = 6). Statistical analyses based on two-way ANOVA with Bonferroni's post hoc test.