Solution structure of the Eps15 homology domain of a human POB1 (partner of RalBP1)

The solution structure of the Eps15 homology (EH) domain of a human POB1 (p artner of RalBP1) has been determined by uniform C-13/N-15 labeling and het eronuclear multidimensional nuclear magnetic resonance spectroscopy. The PO B1 EH domain consists of two EF-hand structures, and the second one binds a calcium ion, In the calcium-bound state, the orientation of the fourth alp ha-helix relative to the other helices of the POB1 EH domain is slightly di fferent from that of calbindin, and much more different from those of calmo dulin and troponin C, on the basis of their atomic coordinates. (C) 1999 Fe deration of European Biochemical Societies.