Translational activator of cytochrome c oxidase I (TACO1)

Translational activator of cytochrome c oxidase I (TACO1) is a mitochondrial protein essential for the specific translation of the mitochondrially encoded cytochrome c oxidase subunit I (COX I or MT-CO1), a key component of complex IV in the mitochondrial respiratory chain[1][3][4][5]. TACO1 binds specifically to the mt-Co1 mRNA and associates with the mitochondrial ribosome to ensure efficient translation, in part by preventing mitoribosome stalling at polyproline stretches found in COX1 and COX3[3][4]. Mutations in TACO1 cause mitochondrial complex IV deficiency, often manifesting as late-onset Leigh syndrome—a neurodegenerative disease characterized by progressive cognitive loss, movement disorders, and basal ganglia lesions[1][3][4][5]. TACO1’s structure contains three domains forming a hook-shaped architecture important for RNA binding[4]. It is not currently recognized as a classical therapeutic target, nor are there approved drugs, biomarkers, or specific safety issues associated with TACO1 modulation.

Other names

Coiled-coil domain-containing protein 44CCDC44PRO0477Translational activator of mitochondrially encoded cytochrome c oxidase ITranslational activator of COX IMC4DN8clone HQ0477 PRO0477p

No known mechanism of action for drugs targeting this molecule; not currently a therapeutic target.