Structure of the regulatory domain of scallop myosin at 2.8 resolution

Article Nature 368, 306 − 312 (1994); doi:10.1038/368306a0 Structure of the regulatory domain of scallop myosin at 2.8 resolution X. Xie, D. H. Harrison, I. Schlichting, R. M. Sweet, V. N. Kalabokis, A. G. Szent−Györgyi & C. Cohen The regulatory domain of scallop myosin is a three−chain protein complex that switches on this motor in response to Ca2+ binding. This domain has been crystallized and the structure solved to 2.8 Å resolution. Side−chain interactions link the two light chains in tandem to adjacent segments of the heavy chain bearing the IQ−sequence motif. The Ca2+−binding site is a novel EF−hand motif on the essential light chain and is stabilized by linkages involving the heavy chain and both light chains, accounting for the requirement of all three chains for Ca2+ binding and regulation in the intact myosin molecul