RPS27A

RPS27A is a human gene that encodes ribosomal protein S27a. The protein is produced as a ubiquitin fusion, consisting of an N-terminal ubiquitin moiety fused to ribosomal protein S27a (Ub–S27a). The ubiquitin portion is cleaved by deubiquitinating enzymes, releasing free ubiquitin and the mature ribosomal protein S27a, which is then incorporated into the small (40S) ribosomal subunit.

Functionally, S27a is a component of the 40S subunit and contributes to the ribosome’s role in translating mRNA into protein. As part of the ribosome, it participates in ribosome biogenesis and the decoding process required for protein synthesis. The protein is conserved across eukaryotes, reflecting its fundamental role in translation.

Genetically, RPS27A is one of several ubiquitin–ribosomal fusion genes in humans. It is broadly expressed, consistent with the essential, housekeeping function of ribosomes across tissues. The mature S27a is a relatively small, basic ribosomal protein that associates with rRNA and other ribosomal proteins within the 40S subunit.

Clinical significance is not tied to a single, well-defined disease, but ribosomal proteins can influence cellular responses to ribosome biogenesis stress and p53 signaling. Altered expression or perturbations in ribosomal protein genes, including RPS27A, have been observed in various cancers, though causal relationships are not established. RPS27A is often considered in the broader context of ribosome biology and its links to cellular growth and stress responses.

Notes: RPS27A is distinct from, but related to, the ubiquitin–ribosomal fusion gene UBA52, which encodes ubiquitin fused to ribosomal protein L40.