Table 2.
Subfamilies of mitochondrial carrier defined by substrate specificity.
| Subfamilies | Aliases | Main Substrates | Triplets * | References |
|---|---|---|---|---|
| For nucleotides and dinucleotides | ||||
| ADP/ATP | AAC | ADP, ATP | 11 (DNS), 19 (AGT), 23 (KL[G/S]), 84 (TYG), 85 (QRX), 88 (NYV) | [19,80] |
| Coenzyme A/PAP | CoA/PAP | - | 23 (K[V/A]Q), 34 (IVR), 88 ([K/Q]SS) | [65,81] |
| ATP-Mg/Pi | APC | ATP-Mg, ATP-Ca, Pi, AXP | 23 (RQ[Q/A]), 30 (DE[A/T/N]), 84 (EYA), 88 (KDS) | [19,76,82,83,84] |
| Thiamine pyrophosphate | TPC | Thpp, thmp; (d)NDP, (d)NTP | 23 (R[T/S]K), 34 (IT[K/R]), 80 (L[A/T]K), 85 (GAT) | [85,86,87] |
| Pyrimidine nucleotides | PNC | Pyrimidine (deoxy)nucleotides | 19 (G[G/A]K), 27 (CNY), 30 ([D/E]WE), 37 (QQR), 83 ([PEP), 85 (R[I/V][S/T]) | [48,88] |
| FAD/folate | FAD | Folates, FAD | 19 (GGK), 27 (HNY), 30 (DWQ) | [70,89,90] |
| ANT | ANT | ATP, ADP, AMP | 19 (SAK), 30 (DAI), 33 (KAK), 37 (QKR) | [46] |
| NAD+ | NDT/PXN | NAD+, (d)AMP, (d)GMP | 19 (GGK), 27 (CNY), 30 (DWE), 89 (FP[L/F]) | [49,68] |
| GTP/GDP | GGC | GTP, GDP, dgtp, dgdp, ITP, IDP | 22 (EGS), 23 (IEL), 84 (QGK), 85 (RSL), 88 (KLS) | [91] |
| For di-/tri-carboxylates and keto acids | ||||
| Dicarboxylates | DIC | Malate, succinate, phosphate, sulfate, thiosulfate | 26 (TG[C/S]), 27 (H[N/T][S/Q/N]), 33 (K[N/M]K), 88 (RQ[I/L/T]) | [42,92,93] |
| Di-/tri-carboxylates | DTC | Oxoglutarate, citrate | 26 (IGS), 27 (QSL), 33 (KLK), 35 (RRQ), 77 (GTY), 84 (YLH), 88 (RMT), 93 ([K/R]DN) | [50] |
| Citrate/isocitrate | SFC | Citrate, isocitrate, aconitate | 22 (EAG), 84 (KNG), 88 (RNT) | [94,95,96] |
| Citrate | CTP | Citrate, malate, isocitrate, cis-aconitate, PEP | 22 (E[A/S][S/T]), 84 (KN[S/D]), 88 (RRV) | [97,98] |
| 2-oxoglutarate | OGC | 2-Oxoglutarate, malate | 26 (VGS), 27 (QTM), 33 (KLK), 35 (RRR), 77 (GTY), 84 (YVH), 88 (RQT), 93 (TSE) | [43,99] |
| Oxodicarboxylates | ODC | Oxoadipate, oxoglutarate | 22 (EE[A/G]), 77 (PTK), 81 (E[H/N]L) 84 (K[F/W]G), 85 (RNG), 88 (KY[M/L]) |
[100,101] |
| Oxaloacetate/sulfate | OAC | Oxaloacetate, sulfate, thiosulfate, a-isopropylmalate | 23 (VAA), 26 (TGM), 30 (E[F/Y]D), 80 (YRR), 84 ([L/M]GH), 88 (RQ[C/S]) | [47,102] |
| For amino acids | ||||
| Glutamate | GC | Glutamate | 22 (GQA), 77 (NTR), 80 (LRV), 84 (EFL), 85 (KSF), 88 (KYA) | [103] |
| Glutamate | BOU | L-Glutamate | - | [104] |
| Aspartate/glutamate | AGC | Aspartate, glutamate, cysteinesulfinate | 22 (GQA), 77 (QCR), 84 (EFQ), 85 (KSF), 88 (KYT) | [45,105] |
| Aspartate/glutamate | UCP1–2 | 23 ([D/E][V/I/S/Q][A/V/T/S]), 88 ([R/K] [D/E][F/M]) | [12,51] | |
| Ornithine | ORC | Ornithine, (lysine, citrulline, arginine, histidine) | 23 ([V/I][A/S]W) but (KSN) in S. cerevisiae, 26 (GL[V/C]) but (ELI) in S. cerevisiae, 84 (EGA), but (QAV) in atbac2 | [106,107,108] |
| Carnitine | CAC | Carnitine, acylcarnitine | 23 (VTW), 85 (FSN) | [44,109] |
| S-adenosylmethionine | SAMC | S-adenosylmethionine, S-adenosylhomocysteine | 19 (G[E/G]G), 23 ([D/E][C/S][A/G]), 26 ([L/F]RT), 80 ([G/A]RW), 85 ([A/S][S/T/D]X), 88 (FQF) | [110,111,112,113] |
| For other substrates | ||||
| Phosphate | PiC, mPT | Phosphate | 19 (CEG), 23 (HDA), 80 (G[R/K]M), 88 (KKQ) | [114,115] |
| Iron | MIT, MRS–4, MFRN–2 | - | 19 (GTG), 22 (E[S/A/H][A/C]), 23 (HDA), 27 ([F/Y][T/N]T) | [12,116] |
Abbreviations: AAC, ADP/ATP carrier; AGC, aspartate/glutamate carrier; ANT, peroxisomal adenine nucleotide translocator; APC, ATP-Mg/Pi carrier; CAC, carnitine carrier; CoA/PAP, coenzyme A/adenosine 3’,5’-diphosphate carrier; BOU, A bout de soufflé (glutamate transporter); CTP, citrate carrier; DIC, dicarboxylate carrier; DTC, di-/tri-carboxylate carrier; FAD, FAD carrier; GC, glutamate carrier, GGC, GTP/GDP carrier; NDT, NAD+ carrier; OAC, oxaloacetate/sulfate carrier; ODC, oxodicarboxylate carrier; OGC, oxoglutarate carrier; ORC, ornithine carrier; PiC, phosphate carrier; mPT, mitochondrial phosphate carrier; PNC, pyrimidine nucleotide carrier; SAMC, S-adenosylmethionine carrier; SFC, succinate/fumarate carrier; TPC, thiamine pyrophosphate carrier; UCP, uncoupling protein. AXP, adenine nucleotides; dNDP, deoxynucleoside diphosphates; dNTP, deoxynucleoside triphosphates; PEP, phosphoenolpyruvate; Pi, phosphate; ThMP, thiamine monophosphate; ThPP, thiamine pyrophosphate. * Symmetry-related amino acid triplets are the triplet sets present in the functionally identified mitochondrial carriers of each family.