• Carles Bosch, Albert Martínez, Nuria Masachs, Cátia M Teixeira, Isabel Fernaud, Fausto Ulloa, Esther Pérez-Martínez, Carlos Lois, Joan X Comella, Javier DeFelipe, Angel Merchán-Pérez, and Eduardo Soriano.
• Developmental Neurobiology and Regeneration Unit, Department of Cell Biology and Parc Cientific de Barcelona, University of Barcelona Barcelona, Spain ; Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Insituto de Salul Carlos III Madrid, Spain ; Institut de Recerca de l'Hospital Universitari de la Vall d'Hebron (VHIR) Barcelona, Spain.
• Front Neuroanat. 2015 Jan 1;9:60.

AbstractThe fine analysis of synaptic contacts is usually performed using transmission electron microscopy (TEM) and its combination with neuronal labeling techniques. However, the complex 3D architecture of neuronal samples calls for their reconstruction from serial sections. Here we show that focused ion beam/scanning electron microscopy (FIB/SEM) allows efficient, complete, and automatic 3D reconstruction of identified dendrites, including their spines and synapses, from GFP/DAB-labeled neurons, with a resolution comparable to that of TEM. We applied this technology to analyze the synaptogenesis of labeled adult-generated granule cells (GCs) in mice. 3D reconstruction of dendritic spines in GCs aged 3-4 and 8-9 weeks revealed two different stages of dendritic spine development and unexpected features of synapse formation, including vacant and branched dendritic spines and presynaptic terminals establishing synapses with up to 10 dendritic spines. Given the reliability, efficiency, and high resolution of FIB/SEM technology and the wide use of DAB in conventional EM, we consider FIB/SEM fundamental for the detailed characterization of identified synaptic contacts in neurons in a high-throughput manner.

5 keywords...

hide…