Richard D. Berlin
Center for Cell Analysis & Modeling

CCAM Faculty

Charles Wolgemuth

Associate Professor of Cell Biology

Contact Information

Research Interests

Living cells are complex machines. Although molecular biology and biochemistry have elucidated a large number of the processes that occur within cells, the physical interplay between a cell and itself or its environment is often overlooked. Recently, with new experimental techniques that can probe subcellular motions and forces, a more complete picture of cellular biology is emerging that shows that the mechanisms underlying cellular processes rely on a complex interaction between the genetic blueprint of the cell and its physical makeup and environment. One such experiment found that the left-right asymmetry in mammals is a consequence of a fluid dynamic instability caused by the rotation of filaments in the developing embryo. This type of evidence strongly suggests that a complete understanding of cellular biology is not possible without physical models that suggest mechanisms by which cells function. My research program focuses on the application of physics, such as elasticity, hydrodynamics and statistical mechanics, to describe cellular morphology, motility and growth. Currently I am working on projects that fall under two classifications and are described below.

Elastic filaments are common building blocks for cells. Alone or in combination with other filaments, they can provide structural integrity while maintaining a necessary degree of flexibility. Bacteria, some of the simplest living organisms, have found many uses for elastic filaments. Two such examples are the flagellum, a rotary oar that propels most swimming bacteria, and mbl, a recently discovered protein that helps maintain form in cylindrical bacteria. My past research dealt with describing the dynamics of elastic filaments in viscous environments and was used to study the dynamics of morphology changes in bacterial flagella and also the supercoiling motions of Bacillus subtilis. I am currently working on projects to understand the morphology and swimming of spirochete bacteria, unique helically shaped cells whose flagella are encased within their cell wall. By rotating these flagella, spirochetes induce shape changes and rotation in their cell wall that propels them through viscous and gelatinous environments. By treating the flagella and the cell wall as coupled elastic filaments, I hope to explain the morphological differences between flagellated and unflagellated spirochetes as well as understanding the mechanism by which rotation of the flagella leads to propulsion.