Diphosphoinositol polyphosphate phosphohydrolase 2 (DIPP-2) (EC 3.6.1.52) (Diadenosine 5',5'''-P1,P6-hexaphosphate hydrolase 2) (Nucleoside diphosphate-linked moiety X motif 4) (Nudix motif 4)
1_MMKFK 6_ PNQTR 11_ TYDRE 16_ GFKKR 21_ AACLC 26_ FRSEQ 31_ EDEVL 36_ LVSSS 41_ RYPDQ 46_ WIVPG 51_ GGMEP 56_ EEEPG 61_ GAAVR 66_ EVYEE 71_ AGVKG 76_ KLGRL 81_ LGIFE 86_ NQDRK 91_ HRTYV 96_ YVLTV 101_ TEILE 106_ DWEDS 111_ VNIGR 116_ KREWF 121_ KVEDA 126_ IKVLQ 131_ CHKPV 136_ HAEYL 141_ EKLKL 146_ GCSPA 151_ NGNST 156_ VPSLP 161_ DNNAL 166_ FVTAA 171_QTSGL
1: Cleaves the beta-phosphate from diphosphoinositol polyphosphates such as PP-InsP5 (diphosphoinositol pentakisphosphate), PP-InsP4 (diphosphoinositol tetrakisphosphate) and [PP]2-InsP4 (bisdiphosphoinositol tetrakisphosphate), suggesting that it may play a role in signal transduction (PubMed:10777568). Diadenosine polyphosphates, particularly Ap6A (P(1),P(6)-bis(5a-adenosyl) hexaphosphate) and Ap5A (P(1),P(5)-bis(5'-adenosyl) pentaphosphate) are downstream effectors of a signaling cascade that regulates cardiac KATP channels, can also be substrates, although with lower preference than the diphosphoinositol polyphosphates (PubMed:10777568). Can also catalyze the hydrolysis of 5-phosphoribose 1-diphosphate, generating the glycolytic activator ribose 1,5-bisphosphate (PubMed:12370170). Does not play a role in U8 snoRNA decapping activity (By similarity). Binds U8 snoRNA (By similarity)