Discovery of myosin I and Pollard-san

In this short review, I describe a brief history of the discovery of myosin I isolated from Acanthamoeba in 1973 by Tom Pollard and Ed Korn. Today, myosins form a large “family tree” that includes more than 30 types of myosins. I discuss the importance of the relationship among actin, myosin, and other actin-binding proteins, many of which were pioneered by Pollard-san (“-san” is a Japanese honorific suffix showing respect, politeness and friendship). At the first conference devoted to actin, Pollard-san, Korn-san, and I discussed the importance of the nucleotide bound at the two ends of the actin filament. I conclude that life is a dynamic accumulation of molecule-molecule bindings, and although we do not yet know how they coordinate with each other to operate a living cell, many enthusiastic and excellent researchers like Pollard-san will unveil mechanisms that will show us what life really looks like.