The Laboratory of Cell Biology explores selected molecular regulatory modules of plant cell polarity and morphogenesis operating mostly at the plasma membrane, at the interface of secretory pathway, membrane lipids and cytoskeleton. Plant morphogenesis is based essentially on two processes - oriented cell division and differential cell growth. As model plants we use angiosperm Arabidopsis and tobacco along with moss Physcomitrella patens. We focus on intracellular molecular mechanisms driving cellular morphogenesis such as exocytosis. Proteins participating in these mechanisms are, despite major differences in cell structure and behaviour, often very similar to those found in the fungal and animal kingdoms. The laboratory is centered around the detailed characterization and regulation of the plant vesicle tethering complex exocyst in various cell types across plant species, including plant-pathogen interactions. A significant aspect of the research is understanding of minor membrane lipids in the maintenance and establishment of cell polarity.