Pioneer neurons in the mouse trigeminal sensory system.

摘要: Pioneer neurons establish preliminary nerve pathways that are followed by later-growing axons. The existence of pioneers and their importance is well documented in invertebrate systems. In mammals, early neuronal development has generally been difficult to study because the size complexity embryos, lack adequate markers. Here we look at time earliest axonal outgrowth mouse embryo using specific monoclonal antibodies stain wholemount preparations. During period formation closure neuropore beginning embryonic day 8.5, can follow trigeminal sensory extending axons along stereotyped pathways. ganglion, an wave neurogenesis gives rise a small number whose pioneer different tracts periphery. After brief pause (12 hr), these primary branch out innervate individual targets. Emerging later, secondary fibers extend pioneers. By contrast, central nervous system, mesencephalic nucleus toward rhombencephalon independently, ignoring preexisting fibers. These results show set peripheral system may be used for guidance later-differentiating neurons.