Fig. 2.

Actin depolymerization and cholesterol extraction induce apical lysosome fusion. (A,B) MDCK cells were treated with nocodazole (Noc) to destabilize microtubules, cytochalasin D (CytoD) to depolymerize actin filaments, methyl-β-cyclodextrin (MBCD) to extract membrane cholesterol or U18666A (U18) to trap cholesterol in lysosomes prior to ionomycin (Iono) treatment. (A) Surface labeling for LAMP2 (green) and ZO-1 (red). (B) β-hex activity in apical and basolateral media. *P<0.01 compared with apical β-hex release from cells treated with ionomycin alone; ^#P<0.01, compared with basolateral release from cells treated with ionomycin alone.