PP2A is a major serine/threonine phosphatase that is implicated in the negative control of cell cycle progression. It is a trimeric holoenzyme that is comprised of a catalytic, structural, and regulatory subunit. PPP2R3B is a regulatory subunit of PP2A. The regulatory subunits of PP2A are grouped into 3 families: B/PR55, B’/PR61, and B’’/PR72. PPP2R3B encodes a 48 kDa B’’ regulatory subunit. PPP2R3B and PP2A, in association with Cdc6, are implicated in cell cycle control via phosphatase activity targeted at DNA replication machinery. serine/threonine-protein phosphatase 2A 48 kDa regulatory subunit B, PP2A subunit B PR48 isoform, PPP2R3L, PR48, NY-REN-8, PPP2R3LY.