MRPS7 (mitochondrial ribosomal protein S7) is a critical component of the small mitochondrial ribosomal subunit that binds to 12S ribosomal RNA and is essential for mitochondrial protein synthesis 1. The protein functions as a structural constituent of the mitoribosome, facilitating assembly of the small ribosomal subunit and enabling translation of mitochondrial-encoded genes necessary for oxidative phosphorylation complexes 1. Mechanistically, MRPS7 stabilizes 12S rRNA transcript levels and supports proper mitochondrial translation, as demonstrated by pulse labeling studies showing impaired mitochondrial protein synthesis when MRPS7 function is compromised 1. Additionally, MRPS7 has been implicated in cancer biology, where it stabilizes β-catenin by inhibiting its ubiquitination, promoting cancer stemness and epithelial-mesenchymal transition that contributes to cisplatin resistance 2. Disease associations include Combined oxidative phosphorylation deficiency 34, with mutations causing congenital sensorineural deafness, progressive hepatic and renal failure, and lactic acidemia due to combined respiratory chain deficiencies 1. MRPS7 variants are also associated with Perrault syndrome, characterized by premature ovarian insufficiency and sensorineural hearing loss 3. Clinically, MRPS7 expression is altered in various conditions including schizophrenia, ischemic stroke, and premature ovarian insufficiency, suggesting potential biomarker applications 456.