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bioRxiv · 10.1101/372813

Radial F-actin Organization During Early Neuronal Development

Abstract

The centrosome is thought to be the major neuronal microtubule-organizing center (MTOC) in early neuronal development, producing microtubules with a radial organization. In addition, albeit in vitro, recent work showed that isolated centrosomes could serve as an actin-organizing center (Farina et al., 2016), raising the possibility that neuronal development may, in addition, require a centrosome-based actin radial organization. Here we report, using super-resolution microscopy and live-cell imaging, F-actin organization around the centrosome with dynamic F-actin aster-like structures with F-actin fibers extending and retracting actively. Photoconversion/photoactivation experiments and molecular manipulations of F-actin stability reveal a robust flux of somatic F-actin towards the cell periphery. Finally, we show that somatic F-actin intermingles with centrosomal PCM-1 satellites. Knockdown of PCM-1 and disruption of centrosomal activity not only affect F-actin dynamics near the centrosome but also in distal growth cones. Collectively the data show a radial F-actin organization during early neuronal development, which might be a cellular mechanism for providing peripheral regions with a fast and continuous source of actin polymers; hence sustaining initial neuronal development.

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BibTeXRIS

Meka, D. P., Scharrenberg, R., Zhao, B., Koenig, T., Schaefer, I., Schwanke, B., Kobler, O., Klykov, S., Richter, M., Eggert, D., Windhorst, S., Dotti, C. G., Kreutz, M. R., Mikhaylova, M., Calderon de Anda, F.. 2018-07-23. Radial F-actin Organization During Early Neuronal Development. https://doi.org/10.1101/372813

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