A nanoscale view on axonal actin –

(Institut de NeuroPhysiopathologie, Marseille)

Abstract: The intricate morphology and molecular identity of axons is maintained for decades, but also continuously adapts to changes in the environment and activity of neurons. Axons fulfill these paradoxical demands thanks to a unique cytoskeletal organization that ensures the coordinated transport, anchoring and mobility of axonal components (1). In our lab, we use super-resolution microscopy to map the nanoscale architecture actin-based structures within the axon. In the axon initial segment, a key compartment for the maintenance of neuronal polarity, we resolved a highly organized assembly encompassing the periodic actin/spectrin scaffold and its partners: ankyrin, myosin (2,3). We have also visualized new actin structures along the axon shaft: rings, hotspots and trails, and are now exploring their molecular organization and functions (4,5). For this, we develop a combination of versatile labeling (6), correlative live-cell/super-resolution/electron microscopy (7) and quantitative analysis (8) that allow for high-content, nanoscale interrogation of the axonal architecture.

1. Leterrier et al. (2017) Nat Rev Neurosci 18:713–726.
2. Leterrier et al. (2015) Cell Rep 13:2781–2793.
3. Berger et al. (2018) Neuron 97:555–570.e6.
4. Ganguly et al. (2015)J Cell Biol 104:20576–417.
5. Chakrabarty et al. (2019) J Cell Biol 218(1):112–24.
6. Almada et al. (2018) Nat Comm 10(1):1223.
7. Vassilopoulos et al. (2019) bioRxiv. doi: 10.1101/636217.
8. Culley et al. (2018) Nat Methods 15:263–266.

Invité par Jean-Bernard Manent

Salle de conférence de l’Inmed – lundi 1er juillet à 11h