Functional Switch of Ribosomal Protein S3 in Translation and DNA Repair

Ribosotrial protein S3 (RPS3), a component of the ribosomal small subunit, is involved in the ribosome biogenesis and protein translation. It has also been demonstrated that RPS3 has many extra-ribosomal functions involved in DNA repair, apoptosis and specific gene transcription regulation. It seems that RPS3 works both in the cytoplasm and nucleus through the association with partner proteins and post-translational modifications. The mechanism of extra-ribosomal RPS3 functions is currently verified in some fields, such as in the DNA repair process and transcription regulation. In this review, we will introduce the various roles of RPS3 as both a ribosome-associated and an extra-ribosomal soluble protein, and discuss a possible mechanism regulating the several functions of RPS3 protein.