Cleaves a beta-phosphate from the diphosphate groups in PP-InsP5 (diphosphoinositol pentakisphosphate), PP-InsP4 and [PP]2-InsP4 (bisdiphosphoinositol tetrakisphosphate), suggesting that it may play a role in signal transduction. Also able to catalyze the hydrolysis of dinucleoside oligophosphate Ap6A, but not Ap5A. The major reaction products are ADP and p4a from Ap6A. Also able to hydrolyze 5-phosphoribose 1-diphosphate. Does not play a role in U8 snoRNA decapping activity. Binds U8 snoRNA.
361-; 5'''-P1; Diadenosine 5'; Diadenosine 5',5'''-P1,P6-hexaphosphate hydrolase 2; diphosphoinositol polyphosphate phosphohydolase type II; Diphosphoinositol polyphosphate phosphohydrolase 2; Diphosphoinositol polyphosphate phosphohydrolase NUDT4B; diphosphoinositol polyphosphate phosphohydrolase type 2; DIPP-2; DIPP-2B; DIPP2; KIAA0487; Nucleoside diphosphate-linked moiety X motif 4; Nucleoside diphosphate-linked moiety X motif 4B; nudix (nucleoside diphosphate linked moiety X)-type motif 4; Nudix hydrolase 4B; Nudix motif 4; Nudix motif 4B; nudix-type motif 4; NUDT4; P6-hexaphosphate hydrolase 2; rDIPP2