R-Type Calcium Channels Are Crucial for Semaphorin 3A-Induced DRG Axon Growth Cone Collapse.
Fiche publication
Date publication
janvier 2014
Auteurs
Membres identifiés du Cancéropôle Est :
Dr BAGNARD Dominique
Tous les auteurs :
Treinys R, Kaselis A, Jover E, Bagnard D, Satkauskas S
Lien Pubmed
Résumé
Semaphorin 3A (Sema3A) is a secreted protein involved in axon path-finding during nervous system development. Calcium signaling plays an important role during axonal growth in response to different guidance cues; however it remains unclear whether this is also the case for Sema3A. In this study we used intracellular calcium imaging to figure out whether Sema3A-induced growth cone collapse is a Ca2+ dependent process. Intracellular Ca2+ imaging results using Fura-2 AM showed Ca2+ increase in E15 mice dorsal root ganglia neurons upon Sema3A treatment. Consequently we analyzed Sema3A effect on growth cones after blocking or modifying intracellular and extracellular Ca2+ channels that are expressed in E15 mouse embryos. Our results demonstrate that Sema3A increased growth cone collapse rate is blocked by the non-selective R- and T- type Ca2+ channel blocker NiCl2 and by the selective R-type Ca2+ channel blocker SNX482. These Ca2+ channel blockers consistently decreased the Sema3A-induced intracellular Ca2+ concentration elevation. Overall, our results demonstrate that Sema3A-induced growth cone collapses are intimately related with increase in intracellular calcium concentration mediated by R-type calcium channels.
Référence
PLoS One. 2014 Jul 17;9(7):e102357