Dynein colocalizes with caveolin-1 proteins. (A) Representative dynein (∼74 kD) bands from a Western blot with rat mesenteric artery protein lysate (rMA) that was immunoprecipitated (IP) with a caveolin-1 (Cav-1) antibody (n = 3) and the total protein lysate as positive control. (B) Representative caveolin-1 (∼22 kD) bands from a Western blot with rMA that was immunoprecipitated with a dynein antibody (n = 3) and the total protein lysate as positive control. Each rMA sample contains n = 3 rats’ worth of mesenteric arteries. No bands for dynein or Cav-1 were detected for the nonspecific binding sample (NS) or for the negative control sample (Neg ctr) where normal rabbit/mouse control IgG was used instead of the specific pulldown antibody. (C i) Representative images of PLA in smooth muscle cells from rat mesenteric arteries with dynein and caveolin-1 antibodies in control (left) and M-βCD–treated (right) cells. Red puncta indicate that target proteins are in close proximity (<40 nM). Scale bars, 10 μm. (C ii) Quantification of the number of PLA puncta in mesenteric artery myocytes (34 cells, n = 4 rats) showing significant decrease of dynein and caveolin-1 colocalization in M-βCD treated cells (**, P = 0.004 according to an unpaired t test). Error bars represent SEM.