Mammalian ribosomal proteins are encoded by multigene families that consist of processed pseudogenes and one functional intron-containing gene within their coding regions. Ribosomal Protein S20, also known as RPS20, is a 119 amino acid cytoplasmic protein that is a component of the 40S ribosomal subunit. Co-transcribed with the small nucleolar RNA gene U54, Ribosomal Protein S20 is a primary binding protein (it binds independently to its target protein) that interacts with both the 5 and 3 minor domains of 16S ribosomal RNA (rRNA). Through its interactions with 16S rRNA, Ribosomal Protein S20 is thought to play a key role in nucleating the assembly of the 30S ribosomal subunit. Like most ribosomal protein-coding genes, the gene encoding Ribosomal Protein S20 is dispersed throughout the genome and exists as multiple processed pseudogenes.
