Paolo Bernardi began his studies on mitochondrial physiology and ion transport under the guidance of Giovanni Felice Azzone, one of the founding Fathers of Bioenergetics. His education in Cellular and Molecular Biology was completed with a long-term stay at the Whitehead Institute for Biomedical Research - Massachusetts Institute of Technology, where he worked under the supervision of Harvey F. Lodish. He pioneered the field of mitochondrial channels and their role in cellular pathophysiology. In particular, he focused on the permeability transition pore (PTP), a high conductance channel that is increasingly recognized as a key player in cell death. During the early 1990s he defined key points of regulation of the PTP in isolated mitochondria (membrane potential, matrix pH, Me2+-binding sites, specific redox-sensitive sites). He then developed tools to reliably monitor mitochondrial function in situ, and addressed mechanistic questions on the PTP as a target in degenerative diseases and cancer.