MOTS-c 40 mg

What is MOTS-c?

MOTS-c is a peptide of 16 amino acids and belongs to the mitochondria-derived peptides (MDP). The name stands for “mitochondrial open reading frame of the 12S rRNA-c” and describes where the sequence is found: it is encoded in a short open reading frame within the 12S rRNA gene of mitochondrial DNA, not in the cell nucleus. The peptide was first described in 2015. MOTS-c is endogenous; the form offered here is produced synthetically and corresponds to the human sequence.

Sequence and key data

• Sequence: Met-Arg-Trp-Gln-Glu-Met-Gly-Tyr-Ile-Phe-Tyr-Pro-Arg-Lys-Leu-Arg
• One-letter code: MRWQEMGYIFYPRKLR
• Termini: free N- and C-terminus (H-…-OH), without acetylation or amidation
• Molecular formula: C101H152N28O22S2
• Molar mass: 2174.6 g/mol (free peptide, without counter-ions)
• PubChem CID: 146675088

The C-terminal end is striking: the last four residues include three basic amino acids (Arg, Lys, Arg), and there is also an arginine at position 2. At neutral pH the molecule therefore carries a positive net charge. The two sulfur atoms in the molecular formula come from the methionines at positions 1 and 6.

Classification: MOTS-c and other peptides

MOTS-c is currently the only member of the Mitochondrial Peptides category. The literature names humanin as a further mitochondrially encoded peptide; it is not listed in the catalogue. Thematically, MOTS-c touches on metabolic research, to which GLP-3 from the incretin analogues is also assigned; structurally, the two molecules are unrelated. The same applies to Glutathione, a tripeptide from redox research that is likewise not structurally related to MOTS-c.

Research context

MOTS-c is studied in cell cultures and rodent models of metabolic homeostasis, with a focus on skeletal muscle tissue. No classical membrane receptor has been identified so far. In the paper that first described the peptide, its cellular activity was linked to inhibition of the folate cycle and the de novo purine biosynthesis coupled to it, which in turn leads to the activation of AMP-activated protein kinase (AMPK). Part of the research accordingly deals with communication between mitochondria and the cell nucleus via folate and AMPK signalling pathways.

Analytics at GPeptides

MOTS-c is supplied in a 10 mg vial; the listed purity is ≥ 97 % (HPLC). Mass spectrometry compares the measured mass with the value from the molecular formula C101H152N28O22S2, i.e. around 2173.11 Da (monoisotopic) or 2174.6 Da (average mass). Because of the four basic residues, the spectrum shows several charge states, which are combined into the molecular mass by deconvolution. Signals 16 Da above the target mass are revealing: they point to an oxidised methionine, a typical minor component of methionine-containing sequences. The peptide is regularly tested externally by HPLC and mass spectrometry; an independent external laboratory is commissioned to carry it out. The available certificates of analysis (COA) can be found in the lab area; if none is listed there yet for MOTS-c, testing is pending. The testing steps involved are described in the guide Quality control.