STED nanoscopy reveals the ubiquity of subcortical cytoskeleton periodicity in living neurons.
In the axons of cultured hippocampal neurons, actin forms various structures, including bundles, patches (involved in the preservation of neuronal polarity), and a recently reported periodic ring-like structure. Nevertheless, the overlaying organization of actin in neurons and in the axon initial segment (AIS) is still unclear, due mainly to a lack of adequate imaging methods. By harnessing live-cell stimulated emission depletion (STED) nanoscopy and the fluorescent probe SiR-Actin, we show that the periodic subcortical actin structure is in fact present in both axons and dendrites. The periodic cytoskeleton organization is also found in the peripheral nervous system, specifically at the nodes of Ranvier. The actin patches in the AIS co-localize with pre-synaptic markers. Cytosolic actin organization strongly depends on the developmental stage and subcellular localization. Altogether, the results of this study reveal unique neuronal cytoskeletal features.
Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
Elisa
E
D'Este
Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
Dirk
D
Kamin
Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
Fabian
F
Göttfert
Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
Ahmed
A
El-Hady
Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany. Electronic address: shell@mpibpc.mpg.de.
Stefan W
SW
Hell
D000199:Actins / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D003599:Cytoskeleton / Q000737:chemistry* / Q000378:metabolism; D003712:Dendrites / Q000737:chemistry / Q000378:metabolism; D005260:Female; D005456:Fluorescent Dyes / Q000737:chemistry / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008856:Microscopy, Fluorescence; D036103:Nanotechnology; D009415:Nerve Net / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D011901:Ranvier's Nodes / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D000199:Actins; D005456:Fluorescent Dyes