Physics of cellular proportions

Dr. Gulliver noticed 140 years ago that the size of the cell\'s nucleus is proportional to the size of the cell. In the intervening years, similar observations have been made about other, large structures that self-assemble in the cell. This raises a fascinating question: How does the cell, which is micrometers in length, measure its size with nothing more at its disposal than nanometer-sized proteins that diffuse, on occasion bump into each other, and transiently stick together? In this talk I will describe quantitative experiments and related theory that reveal general principles of how cells control the size of their internal structures. The case of self-assembly of actin cables in budding yeast is particularly interesting in this context, as it provides an example of a structure whose size is well matched to the size of the cell. I will describe experiments and theory pertaining to actin cables, and the general principles of cellular self-assembly we are learning from this model system.