Pollen tube growth: Getting a grip on cell biology through modeling

Cellular growth in plant, fungal and bacterial cells is based on the mechanical deformation of the cellular envelope by the hydrostatic turgor pressure. Shape generation is therefore a mechanical problem whose biological control is poorly understood. The pollen tube is an attractive model system for the investigation of the growth process in walled cells. The geometry, mechanics and kinetics of the growth process represent intriguing features that are well investigated experimentally. In particular, the presence of regular pulsations in the growth rate, an indicator of non-linear feedback regulation, has attracted the attention of modelers from the engineering, mathematical and physical communities. Here, we summarize important hallmarks characterizing pollen tube growth, and we illustrate how modeling and mathematical analysis have become an integral part of the research programs targeting this cell type.

► Walled cells grow through turgor driven deformation of the wall material and simultaneous assembly of new wall.
► Modeling pollen tube growth correctly predicts the spatial distribution of the rheological properties of the cell wall.
► The cytoskeleton is involved in the spatio-temporal regulation of vesicle secretion.
► Pollen tube growth is oscillatory involving a feedback mechanism based on numerous cellular features.
► A complete description of exocytosis is necessary to understand growth oscillations.