Fig. 1. FM4-64 staining distribution in a growing pollen tube of L.
longiflorum. (A) Typical median focal plane confocal optical section; the
bright field image at 1/3 size appears as an insert. (B) Pixel values along a
central transect through the fluorescence image in (A). (C) Representative
diagram of FM4-64 staining in the L. longiflorum pollen tube apex.
The apical V-shaped `clear zone' of secretory vesicles defined previously
(Lancelle and Hepler, 1992) on
the basis of electron microscopy analysis is shown in relation to the
different `zones' defined by the FM4-64 signal (see text).
