Pannexin 1 regulates ventricular zone neuronal development

• Main Author: Wicki-Stordeur, Leigh
• Other Authors: Swayne, Leigh Anne
• Language: English; en
• Published: 2015
• Subjects: Pannexin; Neural precursor cells; Neurogenesis; Neuronal development; Ventricular zone; Proteomics; Stroke; Crmp2; Ion channel
• Online Access: http://hdl.handle.net/1828/6938

Neurons are generated from unspecialized neural precursor cells (NPCs) in a process termed neurogenesis. This neuronal development continues throughout life in the ventricular zone (VZ) of the lateral ventricles, and the subgranular zone (SGZ) of the dentate gyrus in the hippocampus. NPCs undergo a complex and highly regulated set of behaviours in order to ultimately integrate into the existing brain circuitry as fully functional neurons. Recently the pannexin (Panx) large-pore channel proteins were discovered. One family member, Panx1 is expressed in the nervous system in mature neurons, and acts as an ATP release channel in various cell types throughout the body. Post-natal NPCs are responsive to ATP via activation of purinergic receptors, which modulate a variety of NPC behaviours. I therefore investigated the hypothesis that Panx1 was expressed in post-natal VZ NPCs, where it functioned as an ATP release channel and regulated neuronal development. In the course of my studies, I found that Panx1 positively regulated NPC proliferation and migration, and negatively regulated neurite outgrowth in vitro. Using an NPC-specific Panx1 knock-out strategy, I showed that Panx1 expression was required for maintenance of a consistent population of VZ NPCs in vivo in both healthy and injured brain. Together these data indicated that Panx1 directed NPC behaviours associated with neuronal development both in vitro and in vivo. To further understand the molecular underpinnings of this regulation, I examined the Panx1 interactome, and uncovered a novel association with collapsin response mediator protein 2 (Crmp2). Functional studies suggested that this interaction likely was at least in part responsible for Panx1’s negative impact on neurite outgrowth. Overall, my results represent important novel findings that contribute to our understanding of post-natal neuronal development and the molecular function of Panx1 within the brain. === Graduate === 0317 === 0379 === [e-mail]