5-diphosphoinositol pentakisphosphate 4-kinase activity
5-diphosphoinositol pentakisphosphate 4-kinase activity
Catalysis of the reaction: ATP + 5-diphospho-1D-myo-inositol (1,2,3,4,6)pentakisphosphate = ADP + 4,5-bis(diphospho)-1D-myo-inositol (1,2,3,6)tetrakisphosphate.