Regulatory subunit of protein phosphatase 6 (PP6). May function as a scaffolding PP6 subunit. Involved in the PP6-mediated dephosphorylation of NFKBIE opposing its degradation in response to TNF-alpha (By similarity). Protein phosphatase 6 (PP6) holoenzyme is proposed to be a heterotrimeric complex formed of the catalytic subunit, a SAPS domain-containing subunit (PP6R) and an ankyrin repeat-domain containing regulatory subunit (ARS). Interacts with PPP6C and NFKBIE. Interacts with ANKRD28, ANKRD44 and ANKRD52 (By similarity). Ubiquitous with highest expression in lung, spleen and bladder. Belongs to the SAPS family. Derived from pre-RNA.