I use Vaccinia virus-directed actin polymerisation, a highly photogenic system, to understand how complex signalling networks are organised. My PhD training was in Michael Glotzer’s lab at the University of Chicago, where I studied division plane positioning, primarily in C. elegans embryos. My thesis work helped elucidate a molecular mechanism by which a key molecule, the small GTPase RhoA, is activated on the cell equator, at the right place and time for successful cell cleavage.