OXA1L

OXA1L, or Oxa1-like protein, is a human gene that encodes a mitochondrial inner membrane protein belonging to the OXA1 family of insertases. It is the nuclear-encoded homolog of the bacterial Oxa1 translocase and is conserved across eukaryotes. The protein is localized to the inner mitochondrial membrane and is part of the machinery that handles the insertion and proper folding of membrane proteins.

In mitochondria, OXA1L participates in the insertion and assembly of proteins into the inner membrane, particularly those encoded by the mitochondrial genome. It supports the integration of newly synthesized, mitochondrially encoded subunits of the respiratory chain into the inner membrane and can facilitate the assembly of complex I, III, IV, and V components as part of the broader OXA1-dependent insertion pathway. The protein is thought to interact with mitochondrial ribosomes and other components of the protein import and assembly systems to coordinate translation and membrane insertion.

OXA1L is imported into mitochondria after being synthesized in the cytosol and contains one or more transmembrane regions that anchor it in the inner membrane. Its function is conserved with its prokaryotic counterpart, reflecting the shared ancestry of mitochondrial protein import and insertion mechanisms.

Clinical relevance: Variants in OXA1L have been reported in association with mitochondrial disease in some individuals, often within a spectrum that includes hypotonia, developmental delay, and signs of oxidative phosphorylation deficiency. The phenotypic range and prevalence remain to be fully defined, and research continues to clarify the role of OXA1L in human disease.

Overall, OXA1L is a mitochondrial inner membrane protein that contributes to the insertion and assembly of mitochondrially encoded proteins into the respiratory chain, reflecting its essential role in mitochondrial biogenesis and function.