Officer of the Order of Canada

• Awarded on: May 8, 2003
• Invested on: February 20, 2004

Yoshio Masui is a renowned biologist and scientific pioneer. Professor emeritus at the University of Toronto, he is well known for experiments that have transformed biomedical research. Working with fertilized frogs' eggs, he demonstrated the presence of a protein called maturation promotion factor (MPF) that controls cell division. The discovery of MPF and the characterization of its biochemical properties marked the start of all modern-day research on the regulation of cell division. This work has been critical to understanding the causes of diseases like cancer. Recognized internationally, he has received prestigious awards and is celebrated as one of Canada's finest scientists.