The Scale Invariant Cell

Speaker: Jané Kondev (Brandeis)

Date: 4/15/25

Abstract: Dr. Gulliver noticed 150 years ago that the size of the cell’s nucleus is proportional to the size of the cell. Scaling of other organelles with cell size, such as the mitotic spindle, the nucleolus, mitochondria, has been reported over the years. These observations lead to a puzzle: How do cells measure their own size and incorporate this information in the process of organelle assembly? I will review experiments that support a simple mechanism for detecting the cell volume, which is based on depleting a pool of building blocks in the process of assembly. In some cases, the cell is faced with the challenge of measuring its length to control the self-assembly of a filamentous structure. In this case the limiting pool mechanism does not work. In this talk, I will describe some of our recent experiments and related theory that address the question of how cells measure length. Specifically, our measurements of the length of actin cables in yeast cells have lead us to consider the extreme value statistics in the context of stochastic assembly dynamics, and a new mechanism of length control.