Pseudophosphatases are proteins that are evolutionary related to phosphatases but lack relevant catalytic activity. Proposed functions of pseudophosphatases include: (i) being part of scaffolding signaling complexes; (ii) acting as 'antiphosphatases' that protect specific substrates from other active phosphatases; and (iii) working as functional inhibitors of their substrate. (Adapted from
FBrf0227974.)