Translation in astrocyte distal processes sets molecular heterogeneity at the gliovascular interface

Anne- Cécile Boulay (1, 2, 3, 4) , Bruno Saubaméa (3, 4, 5) , Nicolas Adam (6, 7, 8) , Stéphanie Chasseigneaux (3) , Noémie Mazaré (1, 2) , Alice Gilbert (1, 2) , Mathieu Bahin (9) , Leïla Bastianelli (9) , Corinne Blugeon (10) , Sandrine Perrin (10) , Juliette Pouch (10) , Bertrand Ducos (11) , Stéphane Le Crom (12, 10) , Auguste Genovesio (9) , Fabrice Chrétien (6, 7, 8) , Xavier Declèves (3, 4, 13, 14) , Jean-Louis Laplanche (3, 13, 14, 4) , Martine Cohen-Salmon (1, 2)

1 CIRB - Centre interdisciplinaire de recherche en biologie
2 Labex MemoLife
3 VariaPsy - U1144 - Variabilité de réponse aux Psychotropes
4 UPD5 Pharmacie - Faculté de Pharmacie de Paris - Université Paris Descartes
5 P-MIM - UMS 3612 - Plates-formes mutualisées du centre de recherche pharmaceutique de Paris
6 Histopathologie humaine et Modèles animaux
7 UPD5 - Université Paris Descartes - Paris 5
8 Centre Hospitalier Sainte Anne [Paris]
9 IBENS - Institut de biologie de l'ENS Paris
10 Genomique ENS - GenomiqueENS
11 LPS - Laboratoire de Physique Statistique de l'ENS
12 ADHDG - Analyse des Données à Haut Débit en Génomique
13 UPD7 - Université Paris Diderot - Paris 7
14 USPC - Université Sorbonne Paris Cité

Astrocytes send out long processes that are terminated by endfeet at the vascular surface and regulate vascular functions as well as homeostasis at the vascular interface. To date, the astroglial mechanisms underlying these functions have been poorly addressed. Here we demonstrate that a subset of messenger RNAs is distributed in astrocyte endfeet. We identified, among this transcriptome, a pool of messenger RNAs bound to ribosomes, the endfeetome, that primarily encodes for secreted and membrane proteins. We detected nascent protein synthesis in astrocyte endfeet. Finally, we determined the presence of smooth and rough endoplasmic reticulum and the Golgi apparatus in astrocyte perivascular processes and endfeet, suggesting for local maturation of membrane and secreted proteins. These results demonstrate for the first time that protein synthesis occurs in astrocyte perivascular distal processes that may sustain their structural and functional polarization at the vascular interface.

Keywords: astrocyte; endfeet; gliovascular unit; local translation; mRNAs localization; translating ribosome immunoprecipitation

Domains: Life Sciences [q-bio]

Anne- Cécile Boulay, Bruno Saubaméa, Nicolas Adam, Stéphanie Chasseigneaux, Noémie Mazaré, et al.. Translation in astrocyte distal processes sets molecular heterogeneity at the gliovascular interface. Cell Discovery, 2017, 3 (1), pp.17005. ⟨10.1038/celldisc.2017.5⟩. ⟨inserm-03823110⟩