Tribute to Fumio Oosawa the pioneer in actin biophysics

Fumio Oosawa and his colleagues at Nagoya University laid the foundation for mechanistic studies of actin. Using relatively primitive tools they discovered that actin monomers assemble in a two-step mechanism: highly unfavorable formation of small oligomeric nuclei followed by rapid elongation. Oosawa and his student Sadashi Hatano were the first to purify actin from a nonmuscle cell, Physarum polycephalum, initiating studies of the molecular mechanism of cellular movements.