28S ribosomal protein S7, mitochondrial is a protein that in humans is encoded by the MRPS7 gene.

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. They have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. Another difference between mammalian mitoribosomes and prokaryotic ribosomes is that the latter contain a 5S rRNA. Among different species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology. This gene encodes a 28S subunit protein. In the prokaryotic ribosome, the comparable protein is thought to play an essential role in organizing the 3' domain of the 16 S rRNA in the vicinity of the P- and A-sites. Pseudogenes corresponding to this gene are found on chromosomes 8p and 12p. [provided by RefSeq, Jul 2008].