Assembly factor involved in the biogenesis of the mitochondrial-specific ribosomes (mitoribosomes) ( ). Specifically associates with intermediates of the mitochondrial ribosome large subunit (mt-LSU) and is required for proper ribosome assembly, possibly preventing premature association of the large and small ribosomal subunits ( ). Thereby, indirectly regulates mitochondrial translation ( ). It is also required for complete assembly of the mitochondrial respiratory chain complex I . May also function in DNM1L-mediated mitochondrial fission .
Subcellular locations: Mitochondrion matrix