Human mitochondrial 55S ribosome (mitoribosome) (55S mitoribosome)

The human mitochondrial 55S ribosome, or mitoribosome, is a specialized ribonucleoprotein complex located in the mitochondrial matrix, dedicated to the translation of the 13 essential proteins encoded by the mitochondrial genome (mtDNA) (Amunts et al., Science, 2015). These 13 proteins are critical subunits of the oxidative phosphorylation (OXPHOS) complexes required for cellular ATP production (Greber & Ban, Annu Rev Biochem, 2016). Structurally, the 55S mitoribosome consists of a small 28S subunit and a large 39S subunit, which are distinct from the cytosolic 80S ribosome but share evolutionary ancestry with bacterial 70S ribosomes (Brown et al., Nature, 2014). This structural similarity makes the mitoribosome a frequent off-target for several classes of antibiotics, including oxazolidinones and tetracyclines, which can lead to adverse effects such as myelosuppression and ototoxicity (Wilson, Nat Rev Microbiol, 2014). Beyond antibiotic toxicity, mutations in mitoribosomal proteins or rRNA are linked to various mitochondrial diseases, such as Leigh syndrome and sensorineural hearing loss (Gorman et al., Nat Rev Dis Primers, 2016). Furthermore, the mitoribosome is increasingly recognized as a therapeutic target in oncology, as certain cancers exhibit a dependency on mitochondrial translation for metabolic adaptation and survival (Skrtic et al., Cancer Cell, 2011).

Other names

MitoribosomeMitochondrial ribosome55S ribosomeHuman mitoribosome

Inhibition of mitochondrial protein translation by binding to the 28S or 39S subunits, thereby disrupting the synthesis of essential oxidative phosphorylation components (Wilson, Nat Rev Microbiol, 2014).