Pharmacological approach showing the involvement of electrostatic interactions between NLD and endo-PM in pollen. (A–E) Confocal imaging of mature pollen from line expressing NLD_full:mCitrine after 1-h treatment with mock (DMSO; A) or with 180 µM PAO (B–D), an inhibitor of PI4Ks. After DMSO treatment, NLD_full:mCitrine localized to the endo-PM (A and E), whereas PAO treatment led to three different types of localization: endo-PM (B), noncontinuous (“spotty”) fluorescence signal at endo-PM (C), and low fluorescent signal in cytosol (D). Scale bars = 20 µm. (E) Quantification of drug treatment effect on NLD subcellular localization by counting the three different classes of localization patterns after PAO treatment. Data were obtained from five independent experiments (mean ± SD). ***, significant difference as compared with the mock treatment (P < 0,001; χ² test, n = total number of counted mature pollens).