A Trace ‘Tides Primer: A peptide encoded within mitochondrial DNA

By: Laura Mildon

MOTS-c is a naturally occurring peptide made of 16 amino acids. Its name stands for mitochondrial open reading frame of the 12S rRNA-c. Researchers study it to understand how mitochondrial genetic information may contribute to cellular metabolism and responses to stress.

This article explains its chemical identity, discovery, and selected research. Findings about a naturally occurring peptide or an experimental model do not establish a benefit or intended use for a commercial research material.

What makes its mitochondrial origin distinctive

Mitochondria are compartments within cells that participate in energy conversion and many other processes. They have a small genome of their own, separate from the DNA in the cell nucleus. MOTS-c was identified through a short open reading frame within the mitochondrial 12S ribosomal RNA region.

An open reading frame is a stretch of genetic sequence that can specify a peptide or protein. Ribosomal RNA normally contributes to the machinery that builds proteins; the MOTS-c finding showed that this region also contains a potential peptide-coding sequence.

The original researchers noted that this sequence produces a viable peptide under the standard genetic code used outside mitochondria. The mitochondrial genetic code would instead introduce stop signals. Thus, “mitochondrial-derived” describes its genetic origin; it should not be read as proof that the peptide is assembled inside mitochondria.

Original discovery paper and genetic origin

Chemical identity

These values describe the unmodified peptide with a free amino terminus and free carboxyl terminus in the cited PubChem record. Counterions, hydration, or changes to the sequence or terminal groups require separate chemical identification.

Molecular structure

The sequence specifies the order of the amino acids; the molecular formula only counts atoms. A formula alone cannot uniquely determine a structure. PubChem provides a sequence-specific two-dimensional chemical depiction, showing atom connectivity rather than an experimentally established three-dimensional shape.

View the verified sequence and molecular structure in PubChem

History and discovery

Changhan Lee and colleagues first reported MOTS-c in Cell Metabolism in 2015. They searched mitochondrial DNA for short peptide-coding sequences and combined sequence analysis with laboratory evidence of expression and functional experiments. The discovery broadened research into mitochondria as sources of signaling information.

Selected published research

MOTS-c is not FDA-approved as a medicine. The studies below address biological mechanisms and experimental observations; they do not establish clinical effectiveness or authenticate a commercial product.

Discovery and metabolic signaling in 2015

Lee and colleagues reported the 16-amino-acid sequence and investigated metabolic pathways in cultured cells and mouse models. Their cellular experiments linked MOTS-c to changes in folate and purine metabolism and activation of AMP-activated protein kinase, or AMPK.

AMPK is an enzyme complex involved in cellular energy sensing. The study provided evidence for metabolic signaling in the models examined. It does not establish a weight-management, disease-treatment, or longevity claim for a research product.

Lee and colleagues in Cell Metabolism 2015

Communication with the cell nucleus in 2018

Kim and colleagues investigated MOTS-c in cultured cells under metabolic stress, including glucose restriction. They found that it moved into the nucleus and participated in regulation of stress-responsive gene expression through an AMPK-dependent process.

The nucleus contains most of a cell’s DNA. This work suggests a route through which a peptide encoded by mitochondrial DNA can influence nuclear activity. Results from cultured cells do not establish an outcome in a whole organism.

Kim and colleagues in Cell Metabolism 2018

Exercise observations and experimental models in 2021

Reynolds and colleagues studied MOTS-c in cells and mice and also measured naturally occurring MOTS-c around exercise in a small group of ten young men. The human component examined endogenous peptide levels; it was not a trial of a MOTS-c product.

The paper reported exercise-associated changes in human measurements and physical-performance findings in mice. Those are different types of evidence. They do not establish that a commercial peptide recreates exercise, improves human performance, or extends human lifespan.

Reynolds and colleagues in Nature Communications 2021

What remains unresolved

Important questions include how MOTS-c is produced and transported, which molecular interactions account for its effects, and how findings vary across tissues and experimental conditions. Changes in a signaling pathway or a measured peptide level are not, by themselves, evidence of a clinical benefit.

A study of endogenous MOTS-c asks what the naturally occurring peptide may do. An experiment involving synthetic MOTS-c asks how a specified material behaves in that model. Neither establishes the identity, purity, or performance of a different commercial preparation.

Regulatory context

FDA lists MOTs-C among bulk substances for compounding that may present significant safety risks. Its entry identifies concerns about immune responses, peptide-related impurities, and characterization of the active ingredient. FDA also states that it has not identified human exposure data for drug products containing MOTs-C and lacks important safety information.

This notice concerns drug compounding and safety uncertainty. It should not be described as a blanket prohibition on laboratory research. Research labeling does not establish FDA approval, safety, or permission for another intended use.

FDA notice concerning MOTs-C and compounding risks

Research and regulatory sources checked October 13, 2026.

DISCLAIMER: These statements are for research purposes only and have not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.

Why choose Trace 'Tides? 

Because trust starts with real people, clear answers, and quality you can verify. We have a certified peptide specialist on staff, a phone number that connects you with a real human, and a physical location you can visit by appointment. Call or text us—we’re delighted to answer your questions and address your concerns. We also make checkout straightforward by accepting credit cards, without asking you to use cryptocurrency or connect your bank account to an unfamiliar payment app. And every peptide we sell is tested for purity and endotoxins by licensed U.S. laboratories, so you can choose your research peptides with confidence.