Table_2_Characterization of circular RNAs in dorsal root ganglia after central and peripheral axon injuries.xls

In central nervous system, axons fail to regenerate after injury while in peripheral nervous system, axons retain certain regenerative ability. Dorsal root ganglion (DRG) neuron has an ascending central axon branch and a descending peripheral axon branch stemming from one single axon and serves as a suitable model for the comparison of growth competence following central and peripheral axon injuries. Molecular alterations underpin different injury responses of DRG branches have been investigated from many aspects, such as coding gene expression, chromatin accessibility, and histone acetylation. However, changes of circular RNAs are poorly characterized. In the present study, we comprehensively investigate circular RNA expressions in DRGs after rat central and peripheral axon injuries using sequencing analysis and identify a total of 33 differentially expressed circular RNAs after central branch injury as well as 55 differentially expressed circular RNAs after peripheral branch injury. Functional enrichment of host genes of differentially expressed circular RNAs demonstrate the participation of Hippo signaling pathway and Notch signaling pathway after both central and peripheral axon injuries. Circular RNA changes after central axon injury are also linked with apoptosis and cellular junction while changes after peripheral axon injury are associated with metabolism and PTEN-related pathways. Altogether, the present study offers a systematic evaluation of alterations of circular RNAs in rat DRGs following injuries to the central and peripheral axon branches and contributes to the deciphering of essential biological activities and mechanisms behind successful nerve regeneration.

中枢神经系统（central nervous system, CNS）损伤后轴突无法再生，而外周神经系统（peripheral nervous system, PNS）中的轴突仍保留一定的再生能力。背根神经节（dorsal root ganglion, DRG）神经元由单一根轴突分出上行的中枢轴突分支与下行的外周轴突分支，是对比中枢与外周轴突损伤后生长能力差异的理想模型。针对介导DRG轴突分支产生不同损伤应答的分子改变，已有诸多研究从编码基因表达、染色质开放性及组蛋白乙酰化等多个维度展开探索。然而，目前对环状RNA（circular RNA, circRNA）的表达变化研究仍较为匮乏。本研究通过测序分析，全面探究了大鼠中枢与外周轴突损伤后DRG内的环状RNA表达谱，共鉴定出中枢分支损伤后33个差异表达环状RNA，以及外周分支损伤后55个差异表达环状RNA。对差异表达环状RNA宿主基因的功能富集分析显示，在中枢与外周轴突损伤后，均有Hippo信号通路与Notch信号通路参与其中。中枢轴突损伤后的环状RNA变化还与细胞凋亡及细胞连接相关，而外周轴突损伤后的环状RNA变化则与代谢及PTEN相关通路有关。综上，本研究系统评估了大鼠DRG在中枢与外周轴突分支损伤后的环状RNA表达变化，为解析神经成功再生背后的核心生物学活动与机制提供了重要的研究依据。