Mapping the dynamics and nanoscale organization of synaptic adhesion proteins using monomeric streptavidin.
Nat Comms. 2016-03-16; 7: 10773
Lire sur PubMed
Chamma I(1)(2), Letellier M(1)(2), Butler C(1)(2)(3), Tessier B(1)(2), Lim KH(4), Gauthereau I(1)(2), Choquet D(1)(2)(5), Sibarita JB(1)(2), Park S(4), Sainlos M(1)(2), Thoumine O(1)(2).
(1)Interdisciplinary Institute for Neuroscience, UMR 5297, Centre National de la Recherche Scientifique, 33077 Bordeaux, France.
(2)Interdisciplinary Institute for Neuroscience, University of Bordeaux, 33077 Bordeaux, France.
(3)Imagine Optic, 18 rue Charles de Gaulle, 91400 Orsay, France.
(4)Department of Chemical and Biological Engineering, University at Buffalo, Buffalo, New York 14260, USA.
(5)Bordeaux Imaging Center, UMS 3420 Centre National de la Recherche Scientifique, University of Bordeaux, US 4 INSERM, 33077 Bordeaux, France.
The advent of super-resolution imaging (SRI) has created a need for optimized labelling strategies. We present a new method relying on fluorophore-conjugated monomeric streptavidin (mSA) to label membrane proteins carrying a short, enzymatically biotinylated tag, compatible with SRI techniques including uPAINT, STED and dSTORM. We demonstrate efficient and specific labelling of target proteins in confined intercellular and organotypic tissues, with reduced steric hindrance and no crosslinking compared with multivalent probes. We use mSA to decipher the dynamics and nanoscale organization of the synaptic adhesion molecules neurexin-1β, neuroligin-1 (Nlg1) and leucine-rich-repeat transmembrane protein 2 (LRRTM2) in a dual-colour configuration with GFP nanobody, and show
that these proteins are diffusionally trapped at synapses where they form apposed trans-synaptic adhesive structures. Furthermore, Nlg1 is dynamic, disperse and sensitive to synaptic stimulation, whereas LRRTM2 is organized in compact and stable nanodomains. Thus, mSA is a versatile tool to image membrane proteins at high resolution in complex live environments, providing novel information about the nano-organization of biological structures.