The primary structure of rat ribosomal protein S20

The amino acid sequence of the rat 40 S ribosomal subunit protein S20 was deduced from the sequence of nucleotides in two recombinant cDNAs. Ribosomal protein S20 has 119 amino acids and has a molecular weight of 13,364. Hybridization of the cDNA to digests of nuclear DNA suggests that there are 16-19 copies of the S20 gene. The mRNA for the protein is about 600 nucleotides in length. Rat S20 is homologous to Xenopus laevis S22 and is related to Mycoplasma capricolum S10 and to Escherichia coli S10. The protein contains a possible internal duplication of seven residues.