François Jacob, a pioneer in our understanding of the regulation of gene expression, passed away on Friday. His work with Jacques Monod was foundational to much of the work in my PhD thesis lab and inspired our approach to understanding splicing regulation in my post-doctoral lab. Like many true insights, his realization about a basic mechanism of biology was so basic and fundamental that seemed like the kind of thing we must have known all along. Maybe we did, but until François Jacob we didn’t know we knew it.
Carl Zimmer tells the story of Jacob’s moment of insight:
In the darkness of the Paris movie theater, Jacob hit on an answer. The repressor is a protein that clamps on to E. coli’s DNA, blocking the production of proteins from the genes for beta-galactosidase and the other genes involved in feeding on lactose. A signal, like a switch on a circuit, causes the repressor to stop shutting down the genes…Perhaps these circuits are common in all living things…But when François tried to sketch out his ideas for his wife, he was disappointed.
“You’ve already told me that,” Lise said. “It’s been known for a long time, hasn’t it?” – Carl Zimmer
*Hat tip to Heidi Smith via PZ Myers.