Polar Localization Analysis of Anionic Phospholipids and Their Binding Proteins in Arabidopsis Pollen Tubes

Pollen tubes are typical polarized growth cells whose elongation occurs only in tip regions and is highly dependent on precise and ordered exocytosis/endocytosis in the top regions of the tubes. Although anionic phospholipids have been proven to be involved in regulating vesicle trafficking and the proper localization and functions of proteins in pollen tubes, the underlying cellular and molecular mechanisms remain poorly understood. To further understand how anionic phospholipids are involved in vesicle trafficking and in the control of protein localization and functions, assay methods to analyze the polar localization of anionic phospholipids and their binding proteins, and identifying phospholipid-protein interactions, should be developed. Here, we describe detailed protocols for analyzing anionic phospholipid polar localization and colocalization with their binding proteins in Arabidopsis pollen tubes and examining phospholipid-protein interactions in vitro.