doi:10.1155/2012/329635 Review Article Mitochondria-Ros Crosstalk in the Control of

Copyright © 2012 Saverio Marchi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Reactive oxygen species (ROS) are highly reactivemolecules, mainly generated insidemitochondria that can oxidize DNA, proteins, and lipids. At physiological levels, ROS function as “redox messengers ” in intracellular signalling and regulation, whereas excess ROS induce cell death by promoting the intrinsic apoptotic pathway. Recent work has pointed to a further role of ROS in activation of autophagy and their importance in the regulation of aging. This review will focus on mitochondria as producers and targets of ROS and will summarize different proteins that modulate the redox state of the cell. Moreover, the involvement of ROS and mitochondria in different molecular pathways controlling lifespan will be reported, pointing out the role of ROS as a “balance of power, ” directing the cell towards life or death. 1