During transcriptional phase I (0.25–12 h post nerve injury), the pathways, such as IL-17 signaling pathway, p53 signaling pathway, PPAR signaling pathway, drug metabolism-cytochrome P450, metabolism of xenobiotics by cytochrome P450, and HIF-1 signaling pathway, were enriched; also enriched were calcium signaling pathway, apelin signaling pathway, circadian entrainment, and so on. The gene discussed is PPARA; the disease is injury.