Sophie Dumont: Mastering the uncanny mechanics of living systems

JCB • VOLUME 212 • NUMBER 7 • 2016 744 Sophie Dumont is modest when speaking about her own accomplishments, even though she has studied with some of the best and most creative minds in biophysics and cell biology. But it was a lowly breakdown of her Volkswagen hatchback in graduate school that steered her toward studying biophysics at the cell biology level. As a graduate student with Carlos Bustamante at University of California, Berkeley, Dumont determined how much force it takes to mechanically unfold complex RNA structures (1) and followed how helicase enzymes use ATP to unwind RNA molecules in real time (2). As a postdoctoral fellow with Tim Mitchison at Harvard Medical School in Boston, Dumont switched from singlemolecule studies to probing the mechanics of one of the cell’s most complicated and enigmatic structures, the spindle. By subjecting cellular structures to different forces, she probed how spindle length is regulated (3) and how kinetochores grab and move at the same time (4), both age-old questions. She continued investigating spindle and kinetochore mechanics after setting up her own laboratory at the University of California, San Francisco, in 2012. Her group recently demonstrated how spindles robustly and rapidly repair themselves after laser ablation (5). In a recent conversation with JCB, Dumont explained why the emergent properties of cellular structures differ from those of buildings, and discussed her wanderlust for far-fl ung places and cultures.