exocytosis. The cell is expressing VatM-GFP and DdmCherry- LimED. Found at: doi:10.1371/journal.pone.0008585.s015 (3.37 MB MOV) Movie S12 Increase in phagosome volume and dilution of fluid phase marker prior to premature exocytosis. The cell is expressing VatM-GFP and was incubated for 3 hours with TRITC-dextran, then shifted to unlabeled buffer and observed. Found at: doi:10.1371/journal.pone.0008585.s016 (9.60 MB MOV) Movie S13 Acquisition of GFP-2FYVE label by a vacuole that has separated from a phagosome just prior to premature exocytosis. The cell is expressing GFP-2FYVE and mRFP-LimED; the phagosome contains a FITC-yeast. Found at: doi:10.1371/journal.pone.0008585.s017 (3.86 MB MOV) References 1. Breton S, Brown D (2007) New insights into the regulation of V-ATPase- dependent proton secretion. Am J Physiol Renal Physiol 292: F1–10. 2. Jefferies KC, Cipriano DJ, Forgac M (2008) Function, structure and regulation of the vacuolar (H+)-ATPases. Arch Biochem Biophys 476: 33–42. 3. 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