1. Department of Cell Biology and Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 1
2. The Johns Hopkins University, Baltimore, MD 2
3. Cell Polarity, Migration and Cancer Unit, Institut Pasteur, UMR3691, Université Paris Cité, Centre national de la recherche scientifique, Equipe Labellisée Ligue Contre le Cancer, Paris, France 3