Roland MALLI is a pharmacologist and physiologist with a special research focus on cellular and molecular physiology. With the design, development and usage of novel and improved genetically encoded fluorescent probes different aspects of cell signaling are visualized and quantified with high resolution fluorescence microscopy. In recent years this powerful technique has been successfully applied to investigate distinct aspects of the (sub)cellular Ca2+ and ATP homeostasis of different cell types in physiology and pathology. Currently the role of ATP import into the endoplasmic reticulum (ER) and mitochondrial Ca2+ uptake for cancer cell proliferation and tumorigenesis is investigated. Moreover, a novel class of genetically encoded nitric oxide (NO•) probes has been produced very recently, which enable direct live-cell imaging of NO• dynamics in health and diseases. Roland Malli is an Associated Professor at the Institute of Molecular Biology and Biochemistry of the Medical University of Graz.