Figure 4.
Inhibition of Ppp5 by the TPR domain Glu76 residue resembles inhibition of PP1 by toxins and autoinhibition of PP2B. Superimposition of the phosphatase domains of Ppp5, PP1 in complex with toxins microcystin and calyculin A and the autoinhibited state of PP2B shows a conserved anionic group that contacts the invariant catalytic site Arg-phosphate binding and Tyr residues of these phosphatases. For clarity, only the glutamate residue of microcystin and the phosphate group of calyculin A are shown.