Mitochondrial carrier family

Trichomonas vaginalis, hydrogenosomal membrane Mitochondrial carrier family protein Hmp31 MAQPAEQILIATaSPKPSLSP Dyall et al. (2000)... 

Most of the data available on membrane protein insertion has been generated for members of the mitochondrial carrier family (MCF), particularly for AAC, the model precursor. 

Fig. 7.4. Phylogenetic analysis of the ADP/ATP carriers (AACs) has so far revealed that only the hydrogenosomes of chytrids and ciliates possess genuine mitochondrial AACs, which cluster with the mitochondrial homologues of their aerobic, mitochondria-bearing relatives (2, 3) (Voncken 2001 Voncken et al. 2002a van der Giezen et al. 2002 Tjaden et al. 2004). The AAC of the mitochondrial remnant of Cryptosporidium clusters with the mitochondrial transporters of the distantly related Plasmodium (the closest relative from which a complete genome DNA sequence is available) (1). Trichomonas (5) and Entamoeba (4) use alternative members of the mitochondrial carrier family for the transport of ATP across the hydrogenosomal/mitosomal membranes (Dyall et al. 2000 Tjaden et al. 2004 Chan et al. 2005 Tjaden and Leroch, unpublished results)...

Although remarkable progress has been made in matching the secondary structure and the function in the various members of the mitochondrial carrier family (del Arco and Satrustegui 2005), satisfying information about the function of potential ADP/ATP transporters can only come from a detailed functional analysis (see later). Several methods are currently available reconstitution in liposomes, in vivo expression, rescue experiments, and functional tests in bacteria (Escherichia coli, Lactococcus lactis). Such tests involve competition experiments, effector and inhibitor studies (Voncken 2001 Voncken et al. 2002a Haferkamp et al. 2002 van der Giezen et al. 2002 Tjaden et al. 2004 Chan et al. 2005 Leroch 2006). 

Leroch M (2006) Molekulare, biochemische und physiologische Eigenschaften von Transportproteinen aus der MCF (mitochondrial carrier family) in Pflanzen und Protisten. PhD thesis, Technische Universitat Kaiserslautern, Germany Leroch M, Kirchberger S, Haferkamp I, Wahl M, Neuhaus HE, Tjaden J (2005) Identification and characterization of a novel plastidic adenine nucleotide uniporter from Solanum tuberosum. J Biol Chem 280 17992-18000... 

It was earlier hypothesized that the AAC had been invented either by chlamydiae with subsequent LGT to rickettsiae or by rickettsiae, and was physically but not functionally transferred from the latter to the genome of an amitochondriate host. Similarly to Coxl, also containing 12 transmembrane domains incompatible with import, rickettsial AAC could not be imported into mitochondria, but was later recruited to chloroplasts in a plant lineage (Emelyanov 2001b). Therefore, unrelated mitochondrial AAC - a member of the mitochondrial carrier family proteins containing six transmembrane... 

Membrane import machinery protein mas6 yeast was predicted with a maximum of only two short transmembrane helices 101-116 and 201-215, instead of four expected, but with many potential amphipathic P-strands. High peak in P-amphipathicity just next to the LDL or IDI motif is found at the mas6 yeast residue 69, mpcp rat (from mitochondrial carrier family) residue 83 and achl xenla residue 350. Observed amphipathic P-structure of a leucine rich repeat peptide LRP32 also contains LDL motif [99]. This motif may be important... 

Boss, 0., Samec, S., Paoloni-Giacobino, A., Rossier, C., Dulloo, A., Seydoux, J., Muzzin, P. Giacobino, J. P. (1997). Uncoupling protein-3 a new member of the mitochondrial carrier family with tissue-specific expression. FEES Lett., 408, 39-42. 

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