Effect of mDia1 and ARPC2 depletion/inhibition in mouse salivary glands. (A–D, F, and G) mDia1^{fl/fl Mist1-Cre, mT/mG} (A–D) and ARPC2^{Mist1-Cre, mT/mG} (F and G) mice were injected with 75 mg/kg of TMX. After 4 wk they were injected with 0.01 mg/kg of ISOP (B–D, F, and G) and after 10 min glands were processed for indirect immunofluorescence and imaged with spinning disk microscopy. Some mice were imaged after 6 wk of TMX injection without ISOP stimulation (A). (A) Accumulation of endomembranes in mDia^−/− cells (expressing GFP). Bar, 3 µm. (B) Enlarged granules accumulated in mDia ^−/− but not in mDia^+/+ cells. Bar, 5 µm. (C and D) Salivary glands were labelled with phalloidin (green). (C) mDia1 depletion did not affect the diameter of the APM. Bar, 1 µm. (D) Enlarged granules did not recruit F-actin or in reduced amounts (arrowheads, upper and center panels), when compared with normal size granules (lower panel). Bar, 1 µm. (E) WT mice were treated with 200 µM SMIFH2. Salivary glands were excised, processed for indirect immunofluorescence, and labeled with phalloidin (green) and antibodies against mDia1 (magenta, lower panel) or ARPC2 (magenta, upper panel). Bar, 2 µm. (F) ARPC2 depletion does not affect the diameter of the APM. (G) Accumulation of normal-size granules only in ARPC2 ^−/− but not in ARPC2^+/+ cells. Bar, 4 µm.