MOTS-c: Mitochondrial-Derived Peptide and Metabolic Research
Mar 16, 2026·4 min read
Background
MOTS-c (mitochondrial open reading frame of the 12S rRNA type-c) is a 16-amino acid peptide encoded within the mitochondrial genome, specifically within the 12S ribosomal RNA gene. The peptide was identified and characterized by Lee et al. (2015) in a publication in Cell Metabolism that established MOTS-c as the first mitochondrial-derived peptide (MDP) shown to regulate metabolic homeostasis at the cellular and organismal level.
The discovery of MOTS-c was significant because it demonstrated that mitochondria — traditionally understood as cellular organelles that generate ATP through oxidative phosphorylation — also encode bioactive peptides that function as retrograde signaling molecules. This finding expanded the known repertoire of mitochondrial genome products beyond the 13 well-characterized protein-coding genes and the ribosomal and transfer RNAs.
AMPK Activation and Metabolic Effects
The central finding of Lee et al. (2015) was that MOTS-c treatment activated AMP-activated protein kinase (AMPK) in skeletal muscle cells. AMPK is a highly conserved cellular energy sensor that is activated when intracellular ATP levels decline relative to AMP and ADP. The study demonstrated that MOTS-c activated AMPK through inhibition of the folate cycle and its tethered de novo purine biosynthesis pathway, leading to accumulation of the intermediate metabolite AICAR, an endogenous AMPK activator.
In cultured C2C12 myocytes and HEK293 cells, MOTS-c treatment produced measurable increases in AMPK phosphorylation, as documented by Western blot analysis. Downstream metabolic effects included increased glucose uptake and enhanced fatty acid oxidation, consistent with AMPK activation.
In vivo studies reported that intraperitoneal administration of MOTS-c to mice fed a high-fat diet prevented the development of diet-induced obesity and insulin resistance. Treated mice exhibited lower body weight, reduced fat mass, and improved glucose tolerance compared to vehicle-treated controls.
Exercise and Physical Performance
Reynolds et al. (2021), publishing in Nature Communications, reported that MOTS-c is an exercise-induced mitochondrial-encoded regulator of age-dependent physical decline. The study documented that exercise increased endogenous MOTS-c levels in both skeletal muscle and circulation in human subjects. In young exercising individuals, plasma MOTS-c levels increased significantly following exercise.
The study further demonstrated that MOTS-c treatment improved physical performance in aged mice (22 months old) as measured by treadmill running capacity and grip strength tests. These observations led the authors to characterize MOTS-c as an "exercise mimetic" — a compound that recapitulates certain molecular and physiological responses normally induced by exercise.
Nuclear Translocation and Gene Regulation
Kim et al. (2018), publishing in Cell Metabolism, reported that MOTS-c translocates from the cytoplasm to the nucleus in response to metabolic stress. Using immunofluorescence microscopy and subcellular fractionation, the researchers demonstrated that glucose restriction, oxidative stress, and serum deprivation all triggered nuclear accumulation of MOTS-c.
Within the nucleus, MOTS-c was found to interact with chromatin and regulate the expression of genes involved in the antioxidant response, including genes in the nuclear factor erythroid 2-related factor 2 (NRF2) pathway. These observations were documented using chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq) methodologies.
Laboratory Handling Notes
MOTS-c is supplied as a lyophilized powder and should be stored at -20°C. The peptide is soluble in water and physiological buffers. Due to its small size (16 amino acids), researchers should account for potential losses due to adsorption to laboratory plasticware, and the use of low-binding tubes is recommended.
All findings discussed in this article are derived from peer-reviewed investigations. This compound is intended for research applications only.
References
- Lee, C., et al. "The mitochondrial-derived peptide MOTS-c promotes metabolic homeostasis and reduces obesity and insulin resistance." Cell Metabolism 21.3 (2015): 443-454.
- Reynolds, J.C., et al. "MOTS-c is an exercise-induced mitochondrial-encoded regulator of age-dependent physical decline and muscle homeostasis." Nature Communications 12.1 (2021): 470.
- Kim, S.J., et al. "The mitochondrial-encoded peptide MOTS-c translocates to the nucleus to regulate nuclear gene expression in response to metabolic stress." Cell Metabolism 28.3 (2018): 516-524.
- Kim, S.J., Xiao, J., Cohen, P. "Mitochondrial-derived peptides in aging and age-related diseases." GeroScience 43 (2021): 1113-1121.
