1 Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA.
2 Department of Physics, The University of Chicago, Chicago, IL 60637, USA; James Franck Institute, The University of Chicago, Chicago, IL 60637, USA.
3 Department of Physics, The University of Chicago, Chicago, IL 60637, USA; James Franck Institute, The University of Chicago, Chicago, IL 60637, USA; Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL 60637, USA.
4 Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA; Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA. Electronic address: drkovar@uchicago.edu.
Computational simulations of polymerizing actin filaments indicate that competition for a limiting pool of building blocks is not sufficient to control their length.