ATPase inhibitor, mitochondrial is an enzyme that in humans is encoded by the ATPIF1gene.[5][6]
This gene encodes a mitochondrial ATPase inhibitor. Alternative splicing occurs at this locus and three transcript variants encoding distinct isoforms have been identified.[6]
It prevents ATPase from switching to ATPhydrolysis during collapse of the electrochemical gradient, for example during oxygen deprivation [7] ATP synthase inhibitor forms a one-to-one complex with the F1 ATPase, possibly by binding at the alpha-beta interface. It is thought to inhibit ATP synthesis by preventing the release of ATP.[8] The inhibitor has two oligomeric states, dimer (the active state) and tetramer. At low pH, the inhibitor forms a dimer via antiparallelcoiled coil interactions between the C-terminal regions of two monomers. At high pH, the inhibitor forms tetramers and higher oligomers by coiled coil interactions involving the N terminus and inhibitory region, thus preventing the inhibitory activity.[7]
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