Tau co-organizes dynamic microtubule and actin networks.

Auréliane Elie (1) , Elea Prezel (1) , Christophe Guérin (2) , Eric Denarier (3) , Sacnicte Ramirez-Rios (1) , Laurence Serre (1) , Annie Andrieux (3) , Anne Fourest-Lieuvin (3) , Laurent Blanchoin (2) , Isabelle Arnal (1)

1 GIN - [GIN] Grenoble Institut des Neurosciences
2 LPCV - Laboratoire de physiologie cellulaire végétale
3 GPC - Groupe Physiopathologie du Cytosquelette

The crosstalk between microtubules and actin is essential for cellular functions. However, mechanisms underlying the microtubule-actin organization by cross-linkers remain largely unexplored. Here, we report that tau, a neuronal microtubule-associated protein, binds to microtubules and actin simultaneously, promoting in vitro co-organization and coupled growth of both networks. By developing an original assay to visualize concomitant microtubule and actin assembly, we show that tau can induce guided polymerization of actin filaments along microtubule tracks and growth of single microtubules along actin filament bundles. Importantly, tau mediates microtubule-actin co-alignment without changing polymer growth properties. Mutagenesis studies further reveal that at least two of the four tau repeated motifs, primarily identified as tubulin-binding sites, are required to connect microtubules and actin. Tau thus represents a molecular linker between microtubule and actin networks, enabling a coordination of the two cytoskeletons that might be essential in various neuronal contexts.

Mots clés: Nervous System; Neurons; Cytoskeleton; microtubule/actin crosslinking; Polymerization; Microtubule associated protein; Tau Protein

Domaines: Biologie cellulaire; Neurosciences [q-bio.NC]

Auréliane Elie, Elea Prezel, Christophe Guérin, Eric Denarier, Sacnicte Ramirez-Rios, et al.. Tau co-organizes dynamic microtubule and actin networks.. Scientific Reports, 2015, 5, pp.9964. ⟨hal-01166807⟩