RT Journal Article SR Electronic T1 Filopodyan: an open-source pipeline for the analysis of filopodia JF bioRxiv FD Cold Spring Harbor Laboratory SP 138610 DO 10.1101/138610 A1 Vasja Urbančič A1 Richard Butler A1 Benjamin Richier A1 Manuel Peter A1 Julia Mason A1 Christine E. Holt A1 Jennifer L. Gallop YR 2017 UL http://biorxiv.org/content/early/2017/05/17/138610.abstract AB Filopodia have important sensory and mechanical roles in motile cells. The recruitment of actin regulators, such as ENA/VASP proteins, to sites of protrusion underlies diverse molecular mechanisms of filopodia formation and extension. We developed Filopodyan (filopodia dynamics analysis) in Fiji and R to measure fluorescence in filopodia and at their tips and bases concurrently with their morphological and dynamic properties. Filopodyan supports high-throughput phenotype characterization as well as detailed interactive editing of filopodia reconstructions through an intuitive graphical user interface. Our highly customizable pipeline is widely applicable, capable of detecting filopodia in four different cell types in vitro and in vivo. We use Filopodyan to show that recruitment of ENA and VASP precedes filopodia formation in neuronal growth cones, and uncover a molecular heterogeneity whereby different filopodia display markedly different responses to changes in the accumulation of ENA and VASP in their tips over time.