MOTS-c

MOTS-c arises from a short open reading frame located in the 12S rRNA region of the mitochondrial genome — unlike most peptides it is therefore not encoded by nuclear DNA. Mechanistically, preclinical work describes MOTS-c as modulating the folate cycle and the de novo purine biosynthesis tethered to it, thereby affecting the AMP/ATP ratio and, downstream, AMP-activated protein kinase (AMPK). Under metabolic stress, an AMPK-dependent translocation of the peptide into the cell nucleus and involvement in the regulation of stress-responsive genes (including via antioxidant-response-element-regulated transcription factors) have also been reported. These models derive predominantly from cell culture and rodents; the extent to which they reflect human physiology after administration of exogenous synthetic MOTS-c is not established by human studies.