Figure 4.

Several signalling lipids and the enzymes involved in their synthesis and degradation are localized at the apical plasma membrane. Several phosphoinositides and derived lipids are involved in pollen tube growth regulation. Their specific localisations in the plasma membrane are positional markers in secretory and endocytic processes and can be detected with the help of fluorescent lipid sensors (A). Enzymes acting on lipids of the phosphoinositide network show overlapping localisation to their products (B).