Universite Paris Cite 2 articles published in JoVE Biology Bottom-Up In Vitro Methods to Assay the Ultrastructural Organization, Membrane Reshaping, and Curvature Sensitivity Behavior of Septins Brieuc Chauvin*1, Koyomi Nakazawa*1, Alexandre Beber1,7, Aurélie Di Cicco1, Bassam Hajj1, François Iv2, Manos Mavrakis2, Gijsje H. Koenderink3, João T. Cabral4, Michaël Trichet5, Stéphanie Mangenot*6, Aurélie Bertin*1 1Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, Sorbonne Université, 2Institut Fresnel, CNRS UMR7249, Aix Marseille Univ, Centrale Marseille, 3Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, 4Department of Chemical Engineering, Imperial College London, 5Sorbonne Université, CNRS, Institut de Biologie Paris-Seine (IBPS), Service de microscopie électronique (IBPS-SME), 6Laboratoire Matière et Systèmes Complexes (MSC), Université Paris Cité, 7Institute of Biotechnology, Czech Academy of Sciences, BIOCEV Septins are cytoskeletal proteins. They interact with lipid membranes and can sense but also generate membrane curvature at the micron scale. We describe in this protocol bottom-up in vitro methodologies for analyzing membrane deformations, curvature-sensitive septin binding, and septin filament ultrastructure. Biochemistry Using Microfluidics and Fluorescence Microscopy to Study the Assembly Dynamics of Single Actin Filaments and Bundles Hugo Wioland1, Foad Ghasemi1, Jahnavi Chikireddy1, Guillaume Romet-Lemonne1, Antoine Jégou1 1Université Paris Cité, CNRS, Institut Jacques Monod We present protocols for simple actin filament microfluidic assays, in combination with fluorescence microscopy, that allow one to accurately monitor individual actin filaments in real-time while sequentially exposing them to different protein solutions.
