The axonal growth cone is a specialized structure enabling axon extension and proper guidance to its target by sensing the extracellular environment. A growth cone collapse assay is a popular approach designed to characterize the inhibitory effect of secreted guidance cues in vitro. However, the actin cytoskeleton of the growth cone is very sensitive to various factors like physical impact, temperature, and acidity of environment that may also induce responses resembling those of guidance signals.
View Article and Find Full Text PDFSemaphorin 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.
View Article and Find Full Text PDFRegeneration of embryonic and adult dorsal root ganglion (DRG) sensory axons is highly impeded when they encounter neuronal growth cone-collapsing factor semaphorin3A (Sema3A). On the other hand, increasing evidence shows that DRG axon's regeneration can be stimulated by nerve growth factor (NGF). In this study, we aimed to evaluate whether increased NGF concentrations can counterweight Sema3A-induced inhibitory responses in 15-day-old mouse embryo (E15) DRG axons.
View Article and Find Full Text PDF