Summary: ATP synthase A chain
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MT-ATP6 Edit Wikipedia article
|ATP synthase F0 subunit 6|
|Symbols||; ATPase6; MTATP6|
MT-ATP6 (or ATP6) is a mitochondrial gene encoding the ATP synthase Fo subunit 6 (or subunit/chain A). This subunit belongs to the Fo complex of transmembrane F-type ATP synthase. The MT-ATP6 protein forms one part of a large enzyme called ATP synthase. This enzyme, which is also known as complex V, is responsible for the final step of oxidative phosphorylation. Specifically, one segment of ATP synthase allows positively charged particles, called protons, to flow across a specialized membrane inside mitochondria. Another segment of the enzyme uses the energy created by this proton flow to convert a molecule called adenosine diphosphate (ADP) to ATP. Mutations in the MT-ATP6 gene have been found in approximately 10 to 20 percent of people with Leigh syndrome.
An unusual feature of MT-ATP6 is the 46-nucleotide gene overlap of its first codons with the end of the MT-ATP8 gene. With respect to the MT-ATP6 reading frame (+3), the MT-ATP8 gene ends in the +1 reading frame with a TAG stop codon.
|ATP synthase A chain|
The MT-ATP6 protein weighs 24.8 kDa and is composed of 226 amino acids. The protein is a subunit of the F1Fo ATPase, also known as Complex V, which consists of 14 nuclear- and 2 mitochondrial-encoded subunits. As an A subunit, MT-ATP6 is contained within the non-catalytic, transmembrane Fo portion of the complex. The nomenclature of the enzyme has a long history. The F1 fraction derives its name from the term "Fraction 1" and Fo (written as a subscript letter "o", not "zero") derives its name from being the binding fraction for oligomycin, a type of naturally-derived antibiotic that is able to inhibit the Fo unit of ATP synthase. The Fo region of ATP synthase is a proton pore that is embedded in the mitochondrial membrane. It consists of three main subunits A, B, and C, and (in humans) six additional subunits, d, e, f, g, F6, and 8 (or A6L). 3D structure of E. coli homologue of this subunit was modeled based on electron microscopy data (chain M of ). It forms a transmembrane 4-α-bundle.
This subunit is a key component of the proton channel, and may play a direct role in the translocation of protons across the membrane. Catalysis in the F1 complex depends upon the rotation of the central stalk and Fo c-ring, which in turn is driven by the flux of protons through the membrane via the interface between the F0 c-ring and subunit A. The peripheral stalk links subunit A to the external surface of the F1 domain, and is thought to act as a stator to counter the tendency of subunit A and the F1alpha3 beta3 catalytic portion to rotate with the central rotary element.
Pathogenic variants of the mitochondrial gene MT-ATP6 are known to cause mtDNA-associated Leigh syndrome, a progressive brain disorder that usually appears in infancy or early childhood. Affected children may experience delayed development, muscle weakness, problems with movement, or difficulty breathing. Other variants known to cause mtDNA-associated Leigh syndrome involve MT-TL1, MT-TK, MT-TW, MT-TV, MT-ND1, MT-ND2, MT-ND3, MT-ND4, MT-ND5, MT-ND6 and MT-CO3. Abnormalities in mitochondrial energy generation result in neurodegenerative disorders like Leigh syndrome, which is characterized by an onset of symptoms between 12 months and three years of age. The symptoms frequently present themselves following a viral infection and include movement disorders and peripheral neuropathy, as well as hypotonia, spasticity and cerebellar ataxia. Roughly half of affected patients die of respiratory or cardiac failure by the age of three. Leigh syndrome is a maternally inherited disorder and its diagnosis is established through genetic testing of the aforementioned mitochondrial genes, including MT-ATP6. MT-ATP6 gene mutations associated with Leigh syndrome change one DNA building block (nucleotide) in the MT-ATP6 gene. The most common genetic change replaces the nucleotide thymine with the nucleotide guanine at position 8993 (written as T8993G). The mutations that cause Leigh syndrome impair the function or stability of the ATP synthase complex, inhibiting ATP production and impairing oxidative phosphorylation. Although the exact mechanism is unclear, researchers believe that impaired oxidative phosphorylation can lead to cell death because of decreased energy available in the cell. Certain tissues that require large amounts of energy, such as the brain, muscles, and heart, seem especially sensitive to decreases in cellular energy. Cell death in the brain likely causes the characteristic changes in the brain seen in Leigh syndrome, which contribute to the signs and symptoms of the condition. Cell death in other sensitive tissues may also contribute to the features of Leigh syndrome. A heteroplasmic T→C MT-ATP6 mutation at position 9185 results in the substitution of a highly conserved leucine to proline at codon 220 and a heteroplasmic T→C missense mutation at position 9191 converted a highly conserved leucine to a proline at position 222 of the polypeptide, leading to a Leigh-type phenotype. The T9185C mutation resulted in a mild and reversible phenotype, with 97% of the patient's muscle and blood samples reflecting the mutation. The T9191C mutation presented a much more severe phenotype that resulted in the death of the patient at 2 years of age. Mutations to these oxidative phosphorylation genes have been associated with a variety of neurodegenerative disorders, including Leber's hereditary optic neuropathy (LHON), mitochondrial encephalomyopathy with stroke-like episodes (MELAS) and the previously mentioned Leigh syndrome.
Some of the mutations of the ATP6 gene that cause Leigh syndrome are also responsible for a similar, but less severe, condition called neuropathy, ataxia, and retinitis pigmentosa (NARP). A small number of mutations in the MT-ATP6 gene have been identified in people with NARP. Each of these mutations changes one nucleotide in the MT-ATP6 gene. As in Leigh syndrome, the most common genetic change associated with NARP replaces the nucleotide thymine with the nucleotide guanine at position 8993 (written as T8993G). The mutations that cause NARP alter the structure or function of ATP synthase, reducing the ability of mitochondria to produce ATP. Although the precise effects of these mutations are unclear, researchers continue to investigate how changes in the MT-ATP6 gene interfere with ATP production and lead to muscle weakness, vision loss, and the other features of NARP.
Most of the body's cells contain thousands of mitochondria, each with one or more copies of mitochondrial DNA. The severity of some mitochondrial disorders is associated with the percentage of mitochondria in each cell that has a particular genetic change. People with Leigh syndrome due to a MT-ATP6 gene mutation tend to have a very high percentage of mitochondria with the mutation (from more than 90 percent to 95 percent). The less-severe features of NARP result from a lower percentage of mitochondria with the mutation, typically 70 percent to 90 percent. Because these two conditions result from the same genetic changes and can occur in different members of a single family, researchers believe that they may represent a spectrum of overlapping features instead of two distinct syndromes.
A condition called familial bilateral striatal necrosis, which is similar to Leigh syndrome, can also result from changes in the MT-ATP6 gene. In the few reported cases with these mutations, affected children have had delayed development, problems with movement and coordination, weak muscle tone (hypotonia), and an unusually small head size (microcephaly). Researchers have not determined why MT-ATP6 mutations result in this combination of signs and symptoms in children with bilateral striatal necrosis.
- Anderson S, Bankier AT, Barrell BG, de Bruijn MH, Coulson AR, Drouin J, Eperon IC, Nierlich DP, Roe BA, Sanger F, Schreier PH, Smith AJ, Staden R, Young IG (Apr 1981). "Sequence and organization of the human mitochondrial genome". Nature 290 (5806): 457–65. doi:10.1038/290457a0. PMID 7219534.
- "Entrez Gene: MT-ATP6 mitochondrially encoded ATP synthase 6".
- Zong NC, Li H, Li H, Lam MP, Jimenez RC, Kim CS, et al. (Oct 2013). "Integration of cardiac proteome biology and medicine by a specialized knowledgebase". Circulation Research 113 (9): 1043–53. doi:10.1161/CIRCRESAHA.113.301151. PMC 4076475. PMID 23965338.
- "ATP synthase subunit A, mitochondrial". Cardiac Organellar Protein Atlas Knowledgebase (COPaKB).
- Kagawa Y, Racker E (May 1966). "Partial resolution of the enzymes catalyzing oxidative phosphorylation. 8. Properties of a factor conferring oligomycin sensitivity on mitochondrial adenosine triphosphatase". The Journal of Biological Chemistry 241 (10): 2461–6. PMID 4223640.
- Mccarty RE (Nov 1992). "A plant biochemist's view of H+
-ATPases and ATP synthases". The Journal of Experimental Biology 172 (Pt 1): 431–441. PMID 9874753.
- Carbajo RJ, Kellas FA, Runswick MJ, Montgomery MG, Walker JE, Neuhaus D (Aug 2005). "Structure of the F1-binding domain of the stator of bovine F1Fo-ATPase and how it binds an alpha-subunit". Journal of Molecular Biology 351 (4): 824–38. doi:10.1016/j.jmb.2005.06.012. PMID 16045926.
- "MT-ATP6". Genetics Home Resource. NCBI.
- Thorburn DR, Rahman S (1993–2015). "Mitochondrial DNA-Associated Leigh Syndrome and NARP". In Pagon RA, Adam MP, Ardinger HH, Wallace SE, Amemiya A, Bean LJ, Bird TD, Dolan CR, Fong CT, Smith RJ, Stephens K. GeneReviews [Internet]. Seattle (WA): University of Washington, Seattle.
- Moslemi AR, Darin N, Tulinius M, Oldfors A, Holme E (Oct 2005). "Two new mutations in the MTATP6 gene associated with Leigh syndrome". Neuropediatrics 36 (5): 314–8. doi:10.1055/s-2005-872845. PMID 16217706.
- Baracca A, Sgarbi G, Mattiazzi M, Casalena G, Pagnotta E, Valentino ML, Moggio M, Lenaz G, Carelli V, Solaini G (Jul 2007). "Biochemical phenotypes associated with the mitochondrial ATP6 gene mutations at nt8993". Biochimica et Biophysica Acta 1767 (7): 913–9. doi:10.1016/j.bbabio.2007.05.005. PMID 17568559.
- Torroni A, Achilli A, Macaulay V, Richards M, Bandelt HJ (Jun 2006). "Harvesting the fruit of the human mtDNA tree". Trends in Genetics 22 (6): 339–45. doi:10.1016/j.tig.2006.04.001. PMID 16678300.
- Ingman M, Kaessmann H, Pääbo S, Gyllensten U (Dec 2000). "Mitochondrial genome variation and the origin of modern humans". Nature 408 (6813): 708–13. doi:10.1038/35047064. PMID 11130070.
- Manfredi G, Fu J, Ojaimi J, Sadlock JE, Kwong JQ, Guy J, Schon EA (Apr 2002). "Rescue of a deficiency in ATP synthesis by transfer of MTATP6, a mitochondrial DNA-encoded gene, to the nucleus". Nature Genetics 30 (4): 394–9. doi:10.1038/ng851. PMID 11925565.
- Torigoe T, Izumi H, Ishiguchi H, Uramoto H, Murakami T, Ise T, Yoshida Y, Tanabe M, Nomoto M, Itoh H, Kohno K (Sep 2002). "Enhanced expression of the human vacuolar H+-ATPase c subunit gene (ATP6L) in response to anticancer agents". The Journal of Biological Chemistry 277 (39): 36534–43. doi:10.1074/jbc.M202605200. PMID 12133827.
- Mishmar D, Ruiz-Pesini E, Golik P, Macaulay V, Clark AG, Hosseini S, Brandon M, Easley K, Chen E, Brown MD, Sukernik RI, Olckers A, Wallace DC (Jan 2003). "Natural selection shaped regional mtDNA variation in humans". Proceedings of the National Academy of Sciences of the United States of America 100 (1): 171–6. doi:10.1073/pnas.0136972100. PMC 140917. PMID 12509511.
- Ingman M, Gyllensten U (Jul 2003). "Mitochondrial genome variation and evolutionary history of Australian and New Guinean aborigines". Genome Research 13 (7): 1600–6. doi:10.1101/gr.686603. PMC 403733. PMID 12840039.
- Kong QP, Yao YG, Sun C, Bandelt HJ, Zhu CL, Zhang YP (Sep 2003). "Phylogeny of east Asian mitochondrial DNA lineages inferred from complete sequences". American Journal of Human Genetics 73 (3): 671–6. doi:10.1086/377718. PMC 1180693. PMID 12870132.
- Temperley RJ, Seneca SH, Tonska K, Bartnik E, Bindoff LA, Lightowlers RN, Chrzanowska-Lightowlers ZM (Sep 2003). "Investigation of a pathogenic mtDNA microdeletion reveals a translation-dependent deadenylation decay pathway in human mitochondria". Human Molecular Genetics 12 (18): 2341–8. doi:10.1093/hmg/ddg238. PMID 12915481.
- Reuter TY, Medhurst AL, Waisfisz Q, Zhi Y, Herterich S, Hoehn H, Gross HJ, Joenje H, Hoatlin ME, Mathew CG, Huber PA (Oct 2003). "Yeast two-hybrid screens imply involvement of Fanconi anemia proteins in transcription regulation, cell signaling, oxidative metabolism, and cellular transport". Experimental Cell Research 289 (2): 211–21. doi:10.1016/S0014-4827(03)00261-1. PMID 14499622.
- Dubot A, Godinot C, Dumur V, Sablonnière B, Stojkovic T, Cuisset JM, Vojtiskova A, Pecina P, Jesina P, Houstek J (Jan 2004). "GUG is an efficient initiation codon to translate the human mitochondrial ATP6 gene". Biochemical and Biophysical Research Communications 313 (3): 687–93. doi:10.1016/j.bbrc.2003.12.013. PMID 14697245.
- Coble MD, Just RS, O'Callaghan JE, Letmanyi IH, Peterson CT, Irwin JA, Parsons TJ (Jun 2004). "Single nucleotide polymorphisms over the entire mtDNA genome that increase the power of forensic testing in Caucasians". International Journal of Legal Medicine 118 (3): 137–46. doi:10.1007/s00414-004-0427-6. PMID 14760490.
- Carrozzo R, Rizza T, Stringaro A, Pierini R, Mormone E, Santorelli FM, Malorni W, Matarrese P (Jul 2004). "Maternally-inherited Leigh syndrome-related mutations bolster mitochondrial-mediated apoptosis". Journal of Neurochemistry 90 (2): 490–501. doi:10.1111/j.1471-4159.2004.02505.x. PMID 15228605.
- GeneReviews/NCBI/NIH/UW entry on Mitochondrial DNA-Associated Leigh Syndrome and NARP
- MT-ATP6 protein, human at the US National Library of Medicine Medical Subject Headings (MeSH)
This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.
ATP synthase A chain Provide feedback
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External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR000568
Transmembrane ATPases are membrane-bound enzyme complexes/ion transporters that use ATP hydrolysis to drive the transport of protons across a membrane. Some transmembrane ATPases also work in reverse, harnessing the energy from a proton gradient, using the flux of ions across the membrane via the ATPase proton channel to drive the synthesis of ATP.
There are several different types of transmembrane ATPases, which can differ in function (ATP hydrolysis and/or synthesis), structure (e.g., F-, V- and A-ATPases, which contain rotary motors) and in the type of ions they transport [PUBMED:15473999, PUBMED:15078220]. The different types include:
- F-ATPases (F1F0-ATPases), which are found in mitochondria, chloroplasts and bacterial plasma membranes where they are the prime producers of ATP, using the proton gradient generated by oxidative phosphorylation (mitochondria) or photosynthesis (chloroplasts).
- V-ATPases (V1V0-ATPases), which are primarily found in eukaryotic and they function as proton pumps that acidify intracellular compartments and, in some cases, transport protons across the plasma membrane [PUBMED:20450191]. They are also found in bacteria [PUBMED:9741106].
- A-ATPases (A1A0-ATPases), which are found in Archaea and function like F-ATPases, though with respect to their structure and some inhibitor responses, A-ATPases are more closely related to the V-ATPases [PUBMED:18937357, PUBMED:1385979].
- P-ATPases (E1E2-ATPases), which are found in bacteria and in eukaryotic plasma membranes and organelles, and function to transport a variety of different ions across membranes.
- E-ATPases, which are cell-surface enzymes that hydrolyse a range of NTPs, including extracellular ATP.
F-ATPases (also known as F1F0-ATPase, or H(+)-transporting two-sector ATPase) (EC) are composed of two linked complexes: the F1 ATPase complex is the catalytic core and is composed of 5 subunits (alpha, beta, gamma, delta, epsilon), while the F0 ATPase complex is the membrane-embedded proton channel that is composed of at least 3 subunits (A-C), nine in mitochondria (A-G, F6, F8). Both the F1 and F0 complexes are rotary motors that are coupled back-to-back. In the F1 complex, the central gamma subunit forms the rotor inside the cylinder made of the alpha(3)beta(3) subunits, while in the F0 complex, the ring-shaped C subunits forms the rotor. The two rotors rotate in opposite directions, but the F0 rotor is usually stronger, using the force from the proton gradient to push the F1 rotor in reverse in order to drive ATP synthesis [PUBMED:11309608]. These ATPases can also work in reverse in bacteria, hydrolysing ATP to create a proton gradient.
This entry represents subunit A (or subunit 6) found in the F0 complex of F-ATPases. This subunit is a key component of the proton channel, and may play a direct role in the translocation of protons across the membrane. Catalysis in the F1 complex depends upon the rotation of the central stalk and F0 c-ring, which in turn is driven by the flux of protons through the membrane via the interface between the F0 c-ring and subunit A. The peripheral stalk links subunit A to the external surface of the F1 domain, and is thought to act as a stator to counter the tendency of subunit A and the F1 alpha(3)beta(3) catalytic portion to rotate with the central rotary element [PUBMED:16045926].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Molecular function||hydrogen ion transmembrane transporter activity (GO:0015078)|
|Biological process||ATP synthesis coupled proton transport (GO:0015986)|
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
The graphic that is shown by default represents the longest sequence with a given architecture. Each row contains the following information:
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We make a range of alignments for each Pfam-A family:
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We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.
1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.
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This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.
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|Number in seed:||720|
|Number in full:||1880|
|Average length of the domain:||207.30 aa|
|Average identity of full alignment:||27 %|
|Average coverage of the sequence by the domain:||79.47 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 11927849 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||17|
|Download:||download the raw HMM for this family|
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This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the More....
This chart is a modified "sunburst" visualisation of the species tree for this family. It shows each node in the tree as a separate arc, arranged radially with the superkingdoms at the centre and the species arrayed around the outermost ring.
How the sunburst is generated
The tree is built by considering the taxonomic lineage of each sequence that has a match to this family. For each node in the resulting tree, we draw an arc in the sunburst. The radius of the arc, its distance from the root node at the centre of the sunburst, shows the taxonomic level ("superkingdom", "kingdom", etc). The length of the arc represents either the number of sequences represented at a given level, or the number of species that are found beneath the node in the tree. The weighting scheme can be changed using the sunburst controls.
In order to reduce the complexity of the representation, we reduce the number of taxonomic levels that we show. We consider only the following eight major taxonomic levels:
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Segments of the tree are coloured approximately according to their superkingdom. For example, archeal branches are coloured with shades of orange, eukaryotes in shades of purple, etc. The colour assignments are shown under the sunburst controls. Where space allows, the name of the taxonomic level will be written on the arc itself.
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Some species in the taxonomic tree may not have one or more of the main eight levels that we display. For example, Bos taurus is not assigned an order in the NCBI taxonomic tree. In such cases we mark the omitted level with, for example, "No order", in both the tooltip and the lineage summary.
Unmapped species names
The tree is built by looking at each sequence in the full alignment for the family. We take the name of the species given by UniProt and try to map that to the full taxonomic tree from NCBI. In some cases, the name chosen by UniProt does not map to any node in the NCBI tree, perhaps because the chosen name is listed as a synonym or a misspelling in the NCBI taxonomy.
So that these nodes are not simply omitted from the sunburst tree, we group them together in a separate branch (or segment of the sunburst tree). Since we cannot determine the lineage for these unmapped species, we show all levels between the superkingdom and the species as "uncategorised".
Since we reduce the species tree to only the eight main taxonomic levels, sequences that are mapped to the sub-species level in the tree would not normally be shown. Rather than leave out these species, we map them instead to their parent species. So, for example, for sequences belonging to one of the Vibrio cholerae sub-species in the NCBI taxonomy, we show them instead as belonging to the species Vibrio cholerae.
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For large species trees, you may see blank regions in the outer layers of the sunburst. These occur when there are large numbers of arcs to be drawn in a small space. If an arc is less than approximately one pixel wide, it will not be drawn and the space will be left blank. You may still be able to get some information about the species in that region by moving your mouse across the area, but since each arc will be very small, it will be difficult to accurately locate a particular species.
The tree shows the occurrence of this domain across different species. More...
We show the species tree in one of two ways. For smaller trees we try to show an interactive representation, which allows you to select specific nodes in the tree and view them as an alignment or as a set of Pfam domain graphics.
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For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
We also count the number of unique sequences on which each domain is found, which is shown in green. Note that a domain may appear multiple times on the same sequence, leading to the difference between these two numbers.
Finally, we group sequences from the same organism according to the NCBI code that is assigned by UniProt, allowing us to count the number of distinct sequences on which the domain is found. This value is shown in the pink boxes.
We use the NCBI species tree to group organisms according to their taxonomy and this forms the structure of the displayed tree. Note that in some cases the trees are too large (have too many nodes) to allow us to build an interactive tree, but in most cases you can still view the tree in a plain text, non-interactive representation. Those species which are represented in the seed alignment for this domain are highlighted.
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There are 2 interactions for this family. More...
We determine these interactions using iPfam, which considers the interactions between residues in three-dimensional protein structures and maps those interactions back to Pfam families. You can find more information about the iPfam algorithm in the journal article that accompanies the website.
For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the ATP-synt_A domain has been found. There are 3 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
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