Anti-Ribosomal Protein S3 antibodies are used in the immunodetection of the protein encoded by the RPS3 gene. In humans, the canonical protein has a reported length of 243 amino acid residues and a mass of 26.7 kDa. Its subcellular localization is in the nucleus, mitochondria, and cytoplasm. Alternative splicing is reported to yield 2 different isoforms for this protein. A member of the Universal ribosomal protein uS3 protein family, it is a known component of the small ribosomal subunit. Post-translational modifications have been described, including ubiquitination, sumoylation, protein cleavage and phosphorylation. Other names for this target antigen include uS3, 40S ribosomal protein S3, IMR-90 ribosomal protein S3, small ribosomal subunit protein uS3, and S3.