ATP23, also known as ATP23 metallopeptidase and ATP synthase assembly factor homolog, is a DNA-dependent protein kinase and metalloendopeptidase that in humans is encoded by the ATP23 gene.Zeng, X. et al. (2007). The Metalloprotease Encoded by ATP23 Has a Dual Function in Processing and Assembly of Subunit 6 of Mitochondrial ATPase. Mol Biol Cell. 18(2): 617–626. DOI: 10.1091/mbc.E06-09-0801
ATP23 is the only member of the M76 metallopeptidase family. ATP23 is involved in double-strand break repair (DSB), with higher ATP23 expression increasing the efficiency of the repair. ATP23 has been characterized in yeast, where it is reportedly found in the mitochondrial intermembrane space and is known to associate with the mitochondrial inner membrane.Wilmes, C., Langer, T. (2025). Chapter 83 - ATP23 peptidase. Handbook of Proteolytic Enzymes (Fourth Edition), Academic Press, p. 583-585. ISBN 9780443288494 DOI: https://doi.org/10.1016/B978-0-443-28849-4.00083-7. ATP23 acts as a molecular chaperone during the assembly of ATP synthase, and is known to process the N-terminal propeptide of ATP synthase. ATP23 is also known to act alongside Yme1 to degrade Ups1.
References