RPSA (ribosomal protein SA) is a multifunctional protein with dual roles as a structural component of the small ribosomal subunit and an extracellular receptor. Primarily, RPSA is essential for ribosome biogenesis, as mutations in this gene cause approximately half of all isolated congenital asplenia cases through impaired pre-rRNA processing and disruption of spleen patterning genes 1. Beyond its ribosomal function, RPSA translocates to the cell surface where it acts as a receptor for bacterial pathogens, including Streptococcus suis serotype 2, which exploits RPSA-mediated biomolecular condensation to induce host cell apoptosis 2. RPSA also participates in neuromorphogenesis through PEDF-RPSA-Itga6 signaling, regulating dendritic morphology and cortical development 3. Disease relevance extends to neurodegenerative conditions: RPSA expression is significantly upregulated in Alzheimer's disease brain capillaries alongside elevated protein processing machinery 4, and genome-wide analyses identify RPSA-MOBP loci variants as genetic risk factors for sporadic frontotemporal dementia 5. Clinically, RPSA inhibition shows promise in genetic Alzheimer's disease by modulating endosomal trafficking and reducing amyloidogenic APP processing 6. RPSA's interaction with the cellular prion protein influences tumorigenesis through effects on cell growth, migration, and invasion 7, suggesting broader oncological relevance.