Contents

02 July 1993
Vol 261, Issue 5117

About The Cover

Space-filling representation of myosin subfragment-1, a molecular motor. The colors define the global organization of the polypeptide chains that constitute this molecule. This structure provides the basis for hypotheses for the molecular mechanism of muscle contraction. See pages 50 and 58 and the Perspective on page 35. [Graphics: Adam Steinberg and Ivan Rayment]