The multifaceted mitochondrial OXA insertase

Most mitochondrial proteins are synthesized in the cytosol and transported into mi-tochondria by protein translocases. Yet, mitochondria contain their own genome and gene expression system, which generates proteins that are inserted in the inner membrane by the oxidase assembly (OXA) insertase. OXA contributes to targeting proteins from both genetic origins. Recent data provides insights into how OXA cooperates with the mitochondrial ribosome during synthesis of mitochondrial-encoded proteins. A picture of OXA emerges in which it coordinates insertion of OXPHOS core subunits and their assembly into protein complexes but also participates in the biogenesis of select imported proteins. These functions po-sition the OXA as a multifunctional protein insertase that facilitates protein transport, assembly, and stability at the inner membrane.

Automated summary

Most mitochondrial proteins are synthesized in the cytosol and transported into mitochondria by protein translocases. The oxidase assembly (OXA) insertase in mitochondria plays a role in inserting mitochondrial-encoded proteins into the inner membrane. Recent research reveals the cooperation between OXA and the mitochondrial ribosome during the synthesis of these proteins, suggesting that OXA is a multifunctional protein insertase involved in protein transport, assembly, and stability at the inner membrane.