Mitochondrial Communication in Physiology, Disease and Aging

Mitochondria have tantalized the curiosity of scientists for decades. These organelles have numerous specialized tasks, including being the major source of cellular ATP, the site of fatty acid oxidation, Fe-S biosynthesis and key cellular player in the regulation of Ca2+ homeostasis. In addition to their metabolic roles, they are a multi-versed signaling platform that regulates many cellular processes and functions, including cellular immunity and cell death. In the late 1980s, the discovery of pathological mutations in genes encoding for mitochondrial proteins leading to disease opened a new field aiming to understand how mitochondria communicate with the rest of the cell. Several pathways of communication were found, focusing mostly in signaling pathways transducing mitochondrial stress to the nucleus, thereby affecting gene expression programs. The communication between mitochondria and other organelles remained in obscurity. Not anymore. First, the contact sites between mitochondria and the endoplasmic reticulum provided a remarkable example of inter-organelle communication mediated by physical contacts. Recently, signaling pathways unrelated to contact sites were found to mediate communication between mitochondria and other organelles. This includes organelles such as lysosomes, endoplasmic reticulum, peroxisomes, and even processes like autophagy, employing organelle-specific pathways.

The topic of mitochondrial communication has grown rapidly in the past months, and is showing promise of continued development. It is increasingly accepted that mitochondrial stress (or stress of other organelles, for that matter) cannot be understood simply by looking at that organelle in isolation. A broader overall understanding is required of how the perturbation in one organelle affects others – the brave new world of integrated organelle biology. Furthermore, it is not only mitochondria that affect other organelles; rather, communication goes both ways and the mechanisms need to be studied and discussed. Finally, the signals that mediate the dialogue between organelles need to be explored – Ca2+ is a prime suspect, but reactive oxygen species and metabolites have also been brought to the center of this organelle communication stage.

This Research Topic aims is to present the current knowledge on the mitochondrial communication with other organelles, cellular structures and processes, and its role in physiology, disease and aging. The importance of this communication as a therapeutic target is also a pertinent subject within this Research Topic. We particularly welcome original research, reviews and perspective articles.