Nuclear localization of protein phosphatase 5 is dependent on the carboxy-terminal region

Endogenous and overexpressed protein phosphatase 5 (PP5) localizes to the n ucleus and cytoplasm of HeLa cells, while the overexpressed TPR domain of P P5 is restricted to the cytoplasm, Deletion and mutational analysis of huma n PP5 demonstrates that the C-terminal amino acids 420-499 are essential fo r nuclear localization and PP5 activity is not required. Since the phosphat ase domain terminates at 473, these studies suggest that the highly conserv ed section (476-491) with the eukaryotic consensus FXAVPHPX Phi XPMAYAN is required for nuclear localization of PP5, Bacterially expressed PP5 is inhi bited by several tumor promoters but not by the anticancer drug fostriecin, (C) 2001 Federation of European Biochemical Societies, Published by Elsevi er Science B.V. All rights reserved.