背景
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 that belongs to
the ribosomal protein S18P family.The encoded protein is one of three that has significant
sequence similarity to bacterial S18 proteins.The primary sequences of the three human
mitochondrial S18 proteins are no more closely related to each other than they are to the
prokaryotic S18 proteins. A pseudogene corresponding to this gene is found on chromosome
3p. Alternative splicing results in multiple transcript variants.
