Radial F-actin Organization During Early Neuronal Development

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.

doi:10.1101/372813

bioRxiv · 10.1101/372813

Radial F-actin Organization During Early Neuronal Development

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.

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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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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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