Selective loss of IL-8-mCherry but not Proregion-EGFP from WPBs during a lingering kiss. The image montages in panels A and B show individual WPBs containing both Proregion-EGFP (top panels) and IL-8-mCherry (bottom panels) during a complete exocytotic event (A) or a lingering kiss event (B). Scale bars are 2 μm. Cells were stimulated with 100 μM histamine. In each case the time-course for loss of fluorescence for each protein (as indicated) is shown below. Images were acquired at 30 frames per second. Images shown in the montages were taken at points indicated by the markers i, ii, and iii. Images shown in montages Aii and Bii were at 12 frame intervals during the period indicated by the gray bar. The transient drop in fluorescence of the Proregion-EGFP signal (*) in B was due to a focus change during recording.