ESHS/HSS Annual Meeting

Revisiting the Molecular Turn of the 1960s: The Case of Yoshio Masui’s Cell-Cycle Research

• In Event: Contested Sciences

English Abstract

The 1960s witnessed a transformation of embryological research when molecular biology’s concepts, methods, and techniques were introduced. By this point, many believed that molecular biology had developed enough maturity to be applied to multicellular organisms. While protagonists of molecular biology struggled to extend their theories and methods to higher organisms, embryologists informed by molecular biology and biochemistry began to integrate these disciplines. Classical embryological concepts, experimental methods, and model organism repertoires continue to exert profound influence on the research agendas.

Yoshio Masui’s work on oocyte maturation using cytoplasm transplantation is a valuable exemplifier of this trend. While his research can be viewed as extending the embryological traditions of induction and transplantation, it also shows a deliberate effort to study cell cycle as a biochemically driven process. Masui’s discovery of MPF (maturation promoting factor) and CSF (cytostatic factor) allows researchers to analyze the mechanisms of the cell cycle process in biochemical terms, which aligns with the growing focus on protein regulation. Masui’s findings corrected earlier flawed work by Dettlaff and motivated extensive research on the cell cycle across diverse organisms.

A historical study of Maui’s work provides an understanding of the long-lasting questions shared by embryologists and molecular biologists. It also sheds light on issues such as reduction and scientific progress. I argue that the relationship between embryology and molecular biology in the 1960s cannot simply be captured through the lens of reductionism or Kuhnian paradigm shifts. Instead, it is a complex, mutually generative interaction that led to a significant episode of progress in the life sciences.

Author

• An Zhu, University of Pittsburgh