Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and help in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit. The MRPL50 gene encodes a putative 39S subunit protein, so the MRPL50 protein is classed with the large subunit mitoribosomal proteins.

Mitoribosomes differ from prokaryotic ribosomes in several ways. They have an estimated 75% protein to rRNA composition, whereas in prokaryotic ribosomes this ratio is reversed. Unlike prokaryotic ribosomes, mammalian mitoribosomes also lack a 5S rRNA. Among species, the proteins that make up the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, so they are not easily recognised by sequence homology alone.

UniProt places the protein, named large ribosomal subunit protein mL50, in the mitochondrion-specific ribosomal protein mL50 family, while NCBI Gene assigns the gene to the L47P ribosomal protein family. HGNC lists MRPL50 within the mitochondrial ribosomal proteins and the large subunit mitochondrial ribosomal proteins gene groups. Pseudogenes corresponding to this gene are found on chromosomes 2p, 2q, 5p and 10q, which is worth bearing in mind when designing nucleic acid based experiments. A mouse ortholog, Mrpl50, is recorded.