Expansion Microscopy Allows for The Detection And Characterization of the Diffraction-limited Actin/Spectrin Membrane-associated Periodic Skeleton of Axons

MARTINEZ, GABY F.; QUASSOLLO, GONZALO; WILSON CARLOS; CÁCERES, ALFREDO O.; UNSAIN NICOLÁS

Mar del Plata

Congreso; XXXII Congreso Anual de la Sociedad Argentina de Investigación en Neurociencias.; 2017

SAN

Expansion Microscopy was recently developed to decrease the limit ofresolution of conventional fluorescence microscopy. Fixed biological specimenare embedded in a polymer network, which is then expanded up to ~4-fold inlinear dimension (specimen-gel) and maintains the structure of the specimenand its labeling. In this work, we show the expansion of neuronal cells toidentify the Actin/Spectrin membrane-associated periodic axonal cytoskeleton(MPS), previously characterized using super-resolution nanoscopy (STED andSTORM). We first show that the adaptation of the technique in cell lines stainedfor microtubules, obtaining a consistent expansion of 3.5-fold. Hippocampaland sensory neurons in culture were successfully expanded and the MPS wascharacterized, with a structure indistinguishable from descriptions using superresolution microscopy. This is of interest for future investigations in ourlaboratory and we show preliminary results assessing MPS structure duringaxonal degeneration.