Université PSL

Control and consequences of the physical properties of cells

Control and consequences of the physical properties of cells
Date : 21/02/2019
Lieu : IPGG

Liam Holt, from New York University

Tens of thousands of biochemical reactions occur simultaneously in the cell. Small molecules are channeled through metabolic pathways at blistering speed. Giant complexes assemble to orchestrate transcription and translation. ATP fuels the active transport of organelles along microtubules, and actin networks drive membrane remodeling and agitate the cytoplasm. All of this occurs within a crowded cell interior that approaches the physical limits where jamming will occur. This extreme physical environment is both essential for life, and a potential liability. If cells become too dilute, they senesce and die. On the other hand, increased crowding eventually stalls growth. We found that the central growth regulator, mTORC1, is a crucial regulator of crowding. We also found that mechanical compression affects crowding and phase separation. We propose that perturbations to the physical properties of the cell interior through mechanical forces and the regulation of growth pathways play a crucial role in cell and developmental biology.