Figure 2.

Scheme comparing the classical retrograde signaling pathways in yeast and mammals. In yeast, mitochondrial dysfunction leads to decreases in intracellular ATP concentration, which may favor Rtg2-Mks1 interaction [54] allowing Rtg1-Rtg3 activation. In mammals, mitochondrial dysfunction translates into drops in mitochondrial membrane potential, causing increments in intracellular calcium. Calcium-dependent kinases and phosphatases are then activated culminating with the activation of different transcription factors. Alternative retrograde signaling pathways in yeast, mammals, and other model organisms are discussed in the text.