Fig. 4

Protein phosphatases involved in dephosphorylation of dopamine- and cAMP-regulated phosphoprotein, M _r 32,000 (DARPP-32) at four sites [T34 (Thr34), T75 (Thr75), S97 (Ser97), S130 (Ser130)]. Ser serine, Thr threonine. The protein phosphatases for each site were determined using various preparations of protein phosphatases: Purified protein phosphatases, protein phosphatases in striatal homogenate, protein phosphatases expressed in cells, protein phosphatase inhibitors; X No dephosphorylation. a Preliminary slice data (unpublished observations, A. Nishi), numbers in square brackets References in reference list. PKA Protein kinase A, Cdk 5 cyclin-dependent kinase 5, CK1, -2 casein kinase1, 2, PP protein phosphatase