CXCR7 Receptor Controls the Maintenance of Subpial Positioning of Cajal-Retzius Cells.

Françoise Trousse (1) , Sylvie Poluch (2, 3) , Alessandra Pierani (4) , Annie Dutriaux (4) , Hans H Bock (5) , Takashi Nagasawa (6) , Jean-Michel Verdier (1) , Mireille Rossel (1)

1 MMDN - Mécanismes moléculaires dans les démences neurodégénératives
2 Anatomy, Physiology and Genetics
3 Neuroscience, Uniformed Services University
4 IJM (UMR_7592) - Institut Jacques Monod
5 Gastroenterology, Hepatology and Infectiology Department
6 Department of Immunobiology and Hematology, Institute for Frontier Medical Sciences

Cajal-Retzius (CR) cells are essential for cortical development and lamination. These pioneer neurons arise from distinct progenitor sources, including the cortical hem and the ventral pallium at pallium-subpallium boundary (PSB). CXCR4, the canonical receptor for the chemokine CXCL12, controls the superficial location of hem-derived CR cells. However, recent studies showed that CXCR7, a second CXCL12 receptor, is also expressed in CR cells at early developmental stages. We thus investigated the role of CXCR7 during CR cell development using multiple loss-of-function approaches. Cxcr7 gene inactivation led to aberrant localization of Reelin-positive cells within the pallium. In addition, Cxcr7(-/-) mice were characterized by significant accumulation of ectopic CR cells in the lateral part of the dorsal pallium compared with Cxcr4 knockout mice. Loss-of-function approaches, using either gene targeting or pharmacological receptor inhibition, reveal that CXCR7 and CXCR4 act both in CR positioning. Finally, conditional Cxcr7 deletion in cells derived from Dbx1-expressing progenitors indicates an essential role of CXCR7 in controlling the positioning of a subpopulation of PSB-derived CR cells. Our data demonstrate that CXCR7 has a role in the positioning of hem and PSB-derived CR cells, CXCL12 regulating CR cell subpial localization through the combined action of CXCR4 and CXCR7.

Mots clés: chemokine receptor; Dbx1; Mouse; neocortical development; pallium-subpallium boundary; Reelin

Domaines: Neurosciences [q-bio.NC]

Françoise Trousse, Sylvie Poluch, Alessandra Pierani, Annie Dutriaux, Hans H Bock, et al.. CXCR7 Receptor Controls the Maintenance of Subpial Positioning of Cajal-Retzius Cells.. Cerebral Cortex, 2014, epub ahead of print. ⟨10.1093/cercor/bhu164⟩. ⟨hal-01060863⟩