Study sheds new light on the mechanism of individual cell memory, using yeast as a model

Whi3 is a mnemon (Whi3mnem), or in other words, a protein that stores information in individual cells by forming stable super-assemblies. This memory state is then inherited by only one individual daughter cell at mitosis (individual memory). For example, when facing an uncommitted mating partner, budding yeast cells coalesce the G1/S inhibitor Whi3 into a dominant mnemon super-assembly that drives escape from mating pheromone response. This mnemon state remains stable in the mother cell for many division cycles without being passed to its daughters. How cells maintain and partition the Whi3mnem state at mitosis was largely unknown until now.