Table 1.
Human mitochondrial protein MTases and their targets
| MTase | Abbreviations (accession nr) | Substrate | Abbreviations (accession nr) | Targeted residue (modification type) | Effect of methylation | References |
|---|---|---|---|---|---|---|
| Protein arginine methyltransferase NDUFAF7, mitochondrial | NDUFAF7 (NP_653337) | NADH dehydrogenase [ubiquinone] iron-sulfur protein 2, mitochondrial | NDUFS2 (NP_001364227) | Arg-85a (SDMA) | Promotes Complex I assembly. NDUFAF7 variants associated with pathologic myopia. | (38, 39, 40, 44) |
| Methyltransferase-like protein 9 | METTL9 (NP_057109.3) | NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 3 | NDUFB3 (NP_001244031.1) | His-5, His-7, His-9b (1MH) | Promotes Complex I-dependent mitochondrial respiration. | (12, 47) |
| MTRF1L release factor glutamine methyltransferase | HEMK1 (NP_001304780) | Peptide chain release factor 1-like, mitochondrial | MTRF1L (NP_061914) | Gln-252b (Qme1) | Promotes proper termination of translation. | (53) |
| Electron transfer flavoprotein beta subunit lysine N-methyltransferase |
ETFβ-KMT METTL20 (NP_001129335.1) |
Electron transfer flavoprotein subunit beta | ETFβ (NP_001976.1) | Lys-200, Lys-203b (Kme1, Kme2, Kme3) | Decreases ETF-dependent electron transfer. | (24, 61, 63) |
| Citrate synthase lysine N-methyltransferase, mitochondrial |
CS-KMT METTL12 (NP_001036694.1) |
Citrate synthase, mitochondrial | CS (NP_004068.2) | Lys-395b (Kme1, Kme2, Kme3) | Decreases CS activity. | (68, 69) |
| ATP synthase subunit c lysine N-methyltransferase |
ATPSc-KMT FAM173B (NP_954584.2) |
ATP synthase F(0) complex subunit c, mitochondrial | ATPSc (NP_001002027.1, NP_001002031.1 and NP_001002258.1 precursors produce identical mature protein) | Lys-43a (Kme3) | Promotes ATP synthase assembly and mitochondrial respiration. ATPSc-KMT variants associated with chronic pain. | (83, 84, 85) |
| Adenine nucleotide translocase lysine N-methyltransferase |
ANT-KMT FAM173A (NP_076422.1) |
Adenine nucleotide translocase 1, -2, -3 |
ANT1 (NP_001142.2), ANT2 (NP_001143.2), ANT3 (NP_001627.2) |
Lys-52b (Kme3) | Decreases mitochondrial respiration. | (92) |
Presented data refer to Homo sapiens proteins. Accession numbers according to NCBI database are given for main protein isoforms (1 or a).
a
amino acid numbering based on sequence of mature protein. See Figure 1 for abbreviations of modification types.
b
amino acid numbering based on sequence of precursor protein.