Cleaves a beta-phosphate from the diphosphate groups in PP-InsP5 (diphosphoinositol pentakisphosphate), suggesting that it may play a role in signal transduction. Also able to catalyze the hydrolysis of dinucleoside oligophosphates, with Ap6A and Ap5A being the preferred substrates. The major reaction products are ADP and p4a from Ap6A and ADP and ATP from Ap5A. Also able to hydrolyze 5-phosphoribose 1-diphosphate; however, the relevance of such activity in vivo remains unclear. diphospho-myo-inositol polyphosphate + H2O = myo-inositol polyphosphate + phosphate. H2O + P(1),P(6)-bis(5'-adenosyl) hexaphosphate = adenosine 5'-pentaphosphate + AMP + 2 H(+) H2O + P(1),P(5)-bis(5'-adenosyl) pentaphosphate = adenosine 5'-tetraphosphate + AMP + 2 H(+) Binds 3 Mg(2+) or Mn(2+) ions per subunit. Mn(2+) may be the true cofactor in vivo. Predominantly expressed in brain and is weakly or not expressed in other tissues. Nudt10 and Nudt11 code for identical proteins, which gives their indidual characterization difficult. Thus, most experiments do not discriminate between the 2 proteins. Belongs to the Nudix hydrolase family. DIPP subfamily.