1 Department of Physics, Center for the Physics of Living Cells, and Center for Biophysics and Computational Biology, Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61820, USA. ychemla@illinois.edu tjha@illinois.edu.
2 Department of Physics, Center for the Physics of Living Cells, and Center for Biophysics and Computational Biology, Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61820, USA. Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, Urbana, IL 61820, USA. ychemla@illinois.edu tjha@illinois.edu.