Design Principles of Length Control of Cytoskeletal Structures

TL;DR

This paper reviews how cells regulate the size of cytoskeletal structures through stochastic models of assembly and disassembly, providing testable predictions to distinguish different length-control mechanisms.

Contribution

It introduces simple quantitative models for cytoskeletal length control that generate experimentally testable predictions, advancing understanding of size regulation in cell structures.

Findings

Models predict distinct mechanisms of length control.

Testable predictions differentiate control mechanisms.

Principles applicable to other subcellular structures.

Abstract

Cells contain elaborate and interconnected networks of protein polymers which make up the cytoskeleton. The cytoskeleton governs the internal positioning and movement of vesicles and organelles, and controls dynamic changes in cell polarity, shape and movement. Many of these processes require tight control of the size and shape of cytoskeletal structures, which is achieved despite rapid turnover of their molecular components. Here we review mechanisms by which cells control the size of filamentous cytoskeletal structures from the point of view of simple quantitative models that take into account stochastic dynamics of their assembly and disassembly. Significantly, these models make experimentally testable predictions that distinguish different mechanisms of length-control. While the primary focus of this review is on cytoskeletal structures, we believe that the broader principles and mechanisms discussed herein will apply to a range of other subcellular structures whose sizes are tightly controlled and are linked to their functions.