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Details on Person UniProt:Q9H845 ACAD9

Class:IdReferenceGeneProduct:84419
_chainChangeLogtransit peptide:1- added on Fri February 6 2015;chain:-621 added on Fri February 6 2015;transit peptide:1- for 84419 removed on Fri November 1 2019;chain:-621 for 84419 removed on Fri November 1 2019;transit peptide:1-37 for 84419 added on Fri November 1 2019;chain:38-621 for 84419 added on Fri November 1 2019
_displayNameUniProt:Q9H845 ACAD9
_timestamp2026-02-20 21:36:41
chaintransit peptide:1-37
chain:38-621
checksum064BCE0378877F54
commentFUNCTION Together with NDUFAF1 and ECSIT, forms part of the mitochondrial complex I (MCIA),which is required for the biogenesis of respiratory Complex I (CI) and is therefore crucial for the activation of the oxidative phosphorylation system (PubMed:20816094, PubMed:24158852, PubMed:32320651, PubMed:38086790). ECSIT binding triggers a large conformational change, switching ACAD9 from a fatty acid oxidation (FAO) enzyme to a CI assembly factor (PubMed:38086790). The function in CI assembly is independent of the FAO activity of the protein (PubMed:24158852). As FAO enzyme, it catalyzes the first step in FAO, which consists in the proR-proR stereospecific alpha, beta-dehydrogenation of fatty acyl-CoA thioesters using the electron transfer flavoprotein (ETF) as their physiologic electron acceptor, resulting in the formation of trans-2-enoyl-CoA ((2E)-enoyl-CoA) (PubMed:12359260, PubMed:16020546, PubMed:17564966, PubMed:21237683, PubMed:24158852). Its preferred substrates are both saturated and unsaturated long-chain acyl-CoA substrates, with optimum activity toward the latter (PubMed:12359260, PubMed:16020546, PubMed:17564966, PubMed:21237683, PubMed:24158852). Among the different mitochondrial acyl-CoA dehydrogenases, its FAO activity overlaps with that of ACADV and ACADL, but plays a primary role in tissues where it is the main long-chain ACAD expressed, such as the central nervous system (PubMed:16020546, PubMed:17564966, PubMed:24158852).CATALYTIC ACTIVITY a long-chain 2,3-saturated fatty acyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = a long-chain (2E)-enoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY a medium-chain 2,3-saturated fatty acyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = a medium-chain (2E)-enoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY nonanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E)-nonenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY decanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E)-decenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY undecanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = trans-2-undecenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY tetradecanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E)-tetradecenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY pentadecanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E)-pentadecenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY oxidized [electron-transfer flavoprotein] + hexadecanoyl-CoA + H(+) = (2E)-hexadecenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY heptadecanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = trans-2-heptadecenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY octadecanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E)-octadecenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY eicosanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E)-eicosenoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY (9Z)-hexadecenoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E,9Z)-hexadecadienoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY (9E)-octadecenoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E,9E)-octadecadienoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY oxidized [electron-transfer flavoprotein] + (9Z)-octadecenoyl-CoA + H(+) = (2E,9Z)-octadecadienoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY (9Z,12Z)-octadecadienoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E,9Z,12Z)-octadecatrienoyl-CoA + reduced [electron-transfer flavoprotein]CATALYTIC ACTIVITY (4Z,7Z,10Z,13Z,16Z,19Z)-docosahexaenoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) = (2E,4Z,7Z,10Z,13Z,16Z,19Z)-docosaheptaenoyl-CoA + reduced [electron-transfer flavoprotein]COFACTOR Homodimer (PubMed:16020546). Interacts with NDUFAF1 and ECSIT (PubMed:20816094). Part of the mitochondrial complex I assembly/MCIA complex that comprises at least the core subunits TMEM126B, NDUFAF1, ECSIT and ACAD9 and complement subunits such as COA1 and TMEM186 (PubMed:32320651). Interacts with TMEM70 and TMEM242 (PubMed:33753518).SUBCELLULAR LOCATION Essentially associated with membranes.TISSUE SPECIFICITY Ubiquitously expressed in most normal human tissues and cancer cell lines with higher levels in heart, skeletal muscles, and the central nervous system (where it is the highest expressed ACAD) (PubMed:12359260, PubMed:17564966). Highly expressed (at protein level) in the cerebellum (Purkinje neurons, dentate nucleus, and in the granular layer), where ACADV is not found (PubMed:17564966, PubMed:21237683).DISEASE The disease is caused by variants affecting the gene represented in this entry.SIMILARITY Belongs to the acyl-CoA dehydrogenase family.
descriptionrecommendedName: fullName evidence="19"Complex I assembly factor ACAD9, mitochondrial alternativeName: fullName evidence="18"Acyl-CoA dehydrogenase family member 9 shortName evidence="18"ACAD-9 ecNumber evidence="3"1.3.8.7 ecNumber evidence="2 3 8 12"1.3.8.8
geneNameACAD9
identifierQ9H845
isSequenceChangedFALSE
keyword3D-structure
Acetylation
Disease variant
FAD
Flavoprotein
Membrane
Mitochondrion
Mitochondrion inner membrane
Oxidoreductase
Phosphoprotein
Primary mitochondrial disease
Proteomics identification
Reference proteome
Transit peptide
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9917590] Weiser, Joel, 2024-08-09
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9939033] Weiser, Joel, 2025-02-21
[InstanceEdit:9948485] Weiser, Joel, 2025-05-21
[InstanceEdit:9983091] Weiser, Joel, 2026-02-20
nameACAD9
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:8989351] ENSEMBL:ENSG00000177646 ACAD9 [Homo sapiens]
secondaryIdentifierACAD9_HUMAN
D3DNB8
Q8WXX3
sequenceLength621
species[Species:48887] Homo sapiens
(referenceEntity)[EntityWithAccessionedSequence:5689049] ACAD9 [mitochondrial inner membrane] [Homo sapiens]
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No pathways have been reviewed or authored by UniProt:Q9H845 ACAD9 (84419)
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