Neuronal activity remodels the F-actin based submembrane lattice in dendrites but not axons of hippocampal neurons.

TitleNeuronal activity remodels the F-actin based submembrane lattice in dendrites but not axons of hippocampal neurons.
Publication TypeJournal Article
Year of Publication2020
AuthorsLavoie-Cardinal F, Bilodeau A, Lemieux M, Gardner M-A, Wiesner T, Laramée G, Gagné C, De Koninck P
JournalSci Rep
Volume10
Issue1
Pagination11960
Date Published2020 Jul 20
ISSN2045-2322
Abstract

The nanoscale organization of the F-actin cytoskeleton in neurons comprises membrane-associated periodical rings, bundles, and longitudinal fibers. The F-actin rings have been observed predominantly in axons but only sporadically in dendrites, where fluorescence nanoscopy reveals various patterns of F-actin arranged in mixed patches. These complex dendritic F-actin patterns pose a challenge for investigating quantitatively their regulatory mechanisms. We developed here a weakly supervised deep learning segmentation approach of fluorescence nanoscopy images of F-actin in cultured hippocampal neurons. This approach enabled the quantitative assessment of F-actin remodeling, revealing the disappearance of the rings during neuronal activity in dendrites, but not in axons. The dendritic F-actin cytoskeleton of activated neurons remodeled into longitudinal fibers. We show that this activity-dependent remodeling involves [Formula: see text] and NMDA receptor-dependent mechanisms. This highly dynamic restructuring of dendritic F-actin based submembrane lattice into longitudinal fibers may serve to support activity-dependent membrane remodeling, protein trafficking and neuronal plasticity.

DOI10.1038/s41598-020-68180-2
PubMed ID32686703
PubMed Central IDPMC7371643

Funding

Our research endeavors are made possible by the following agencies:

Canadian Institutes of Health Research - Instituts de recherche en santé du Canada Fonds de recherche du Québec – Nature et technologies (FRQNT)Fonds de la recherche en santé du Québec  Natural Sciences and Engineering Research Council of Canada (NSERC) - Conseil de recherche en sciences naturelles et en génie du Canada (CRSNG)innovation.caHuman Frontier Science ProgramCanada First Research Excellence FundSentinelle Nord