CALCIUM

Ca2+ is involved in an intriguing variety of different biological even ts. The rapid development of techniques such as region-or organelle-di rected fluorescent probes and laser scanning confocal microscopy for s tudying cellular biological events at a molecular level provides us wi th a rich daily intake of new results. While detailed three-dimensiona l structures of many intracellular and extracellular Ca2+-binding prot eins have become available, structural information on key membrane pro teins is still tacking. An integrated picture of the molecular events behind the multifunctional roles of Ca2+ in biological systems is stil l pending.