Membrane Proteins – How do membrane transporters convert ion translocation into growth speed?
Our working hypothesis is that ion channels and pumps in the plasma membrane generate an electrical field around the pollen grain and the growing tube, which provides a 3-dimensional, polar electrical field for the tube’s growth direction. The various ion transporters are the pollen permeome (Pertl-Obermeyer et al (2018)) and can be characterized by electrophysiological techniques using pollen protoplasts in patch-clamp experiments but also in organelle-enriched vesicle preparations. In addition, synthetic biology methods are used for in-vitro production and reconstitution of ion transporters in liposomes (Large Unilamellar and Giant Unilamellar Vesicles, LUVs and GUVs) for detailed investigations. We are currently characterizing K+ channels, H+ ATPases, and aquaporins of the pollen plasma membrane.