Acknowledgements We are very grateful to numerous colleagues for their generous help and support: Michael Altmann (Dept. of Molecular Medicine) for the use of his French press, Aline Schmid (this laboratory) for her patience in optimizing its application, Staurosporine molecular weight Gabriela Marti (this laboratory) for cAMP determinations, Mascha Pusnik and André Schneider (Dept. of Chemistry and Biochemistry)

for help with ATP determinations and RNA interference, Thomas Werner (ETH Zurich) for his help with polyphosphate measurements, Xuan Lan Vu (this laboratory) for measuring PDE activities, Théo Baltz (University of Bordeaux) for his generous gift of VH+-PPase antibody, and to Pascal Maeser (Swiss Institute for Tropical and Public Health, Basel) for many thoughtful comments. This work was supported BIBW2992 by grant Nr 3100A-109245 of the Swiss National Science Foundation. All experiments involving animals were done according to the regulations of the Federal Commission for Animal Experimentation and under the supervision of the Cantonal Office of Agriculture. References 1. Rao NN, Gomez-Garcia MR, Kornberg A: Inorganic polyphosphate: Essential for growth and survival. Annu Rev Biochem 2009, 78: 35.1–35.43.CrossRef 2. Brown MRW, Kornberg A: The long and

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