Direct regulator of SIRT1. Enhances SIRT1-mediated deacetylation of p53/TP53, thereby participating in inhibition of p53/TP53-mediated transcriptional activity. Interacts with RPS19 (By similarity). Interacts with SIRT1. Widely expressed (at protein level). Citrullinated by PADI4. Belongs to the AROS family.