Schwann cell-secreted PGE2 promotes sensory neuron excitability during development [RNA-Seq]

Electrical excitability—the ability to fire and propagate action potentials—is a signature feature of neurons. How neurons become excitable during development and whether excitability is an intrinsic property of neurons or requires signaling from glial cells remain unclear. Here, we demonstrate that Schwann cells, the most abundant glia in the peripheral nervous system, promote somatosensory neuron excitability during development. We find that Schwann cells secrete prostaglandin E2, which is necessary and sufficient to induce developing somatosensory neurons to express normal levels of genes required for neuronal function, including voltage gated sodium channels, and to fire action potential trains. In this RNA-Seq study, we discovered that treating cultured DRG neurons with Schwann cell-conditioned media or PGE2 increased the expression of several genes required for neuronal maturation and excitability, including voltage-gated sodium channels.电兴奋性（Electrical excitability）——即触发并传播动作电位（action potential）的能力——是神经元的标志性特征。神经元在发育过程中如何获得兴奋性，以及兴奋性是神经元的固有属性还是需要胶质细胞的信号调控，目前仍不明确。本研究证实，作为周围神经系统（peripheral nervous system）中数量最多的胶质细胞，雪旺细胞（Schwann cells）可在发育过程中促进体感神经元的兴奋性。我们发现，雪旺细胞会分泌前列腺素E2（prostaglandin E2），该物质既可诱导发育中的体感神经元正常表达神经元功能所需的多种基因（包括电压门控钠通道（voltage-gated sodium channels）），又足以触发其产生动作电位串。在本次RNA测序（RNA-Seq）研究中，我们发现，使用雪旺细胞条件培养基或PGE2处理体外培养的背根神经节（dorsal root ganglion, DRG）神经元，可上调神经元成熟与兴奋性所需的多种基因的表达，其中包括电压门控钠通道。