lncRNA-MEG3通过miR-770-5p影响肠神经嵴细胞迁移和增殖在先天性巨结肠发生中的作用

The pathogenesis of Hirschsprung’s disease (HSCR) is highly associated with the migration and proliferation failure of the enteric neural crest-derived cells (ENCCs), but the concrete mechanism is still unclear. In this study, an initial screening of lncRNA expression was performed through lncRNA microarray, lncRNA-MEG3 was one most aberrant down-regulated lncRNA after analyzing the result. The bioinformatics analysis indicated that the miR-770-5p was coded by the rearmost intron of lncRNA-MEG3 while SRGAP1 was the potential target gene of miR-770-5p. It was confirmed that lncRNA-MEG3 and miR-770-5p were underexpressed and that SRGAP1 was overexpressed in pathologic tissues of HSCR patients when compared with normal controls. Moreover, in vitro assay, the down-regulated of lncRNA-MEG3 and miR-770-5p could restrict the migration and proliferation of nerve cells while increase the expression of SRGAP1 gene. Based on the findings above, we made the hypothesis that lncRNA-MEG3 affected the migration and proliferation of ENCCs through down-regulated of miR-770-5p with the up-regulated of SRGAP1, which was involved in the pathogenesis of HSCR..Our research aims to investigate the mechanism of how lncRNA-MEG3 affected the migration and proliferation of ENCCs through miR-770-5p and the mediation of SRGAP1 expression. We will identify its role in the occurrence of HSCR in vitro experiments, providing a new perspective for the study of the etiology of HSCR.

肠神经嵴细胞（ENCCs）迁移增殖障碍是先天性巨结肠（HSCR）发生的主要原因，但具体机制尚不明确。我们采用lncRNA芯片筛选HSCR病变段发现MEG3显著低表达。生物信息学显示MEG3基因的一个内含子编码miR-770-5p，而SRGAP1是miR-770-5p的靶基因。人群验证发现MEG3、miR-770-5p在HSCR病变段呈一致性低表达，SRGAP1高表达。体外分别干扰或抑制MEG3及miR-770-5p表达均影响神经细胞迁移增殖，并伴随着SRGAP1表达上调。由此设想：MEG3通过其内在miR-770-5p低表达，引起靶基因SRGAP1表达增加，影响ENCCs向消化道迁移增殖，从而与HSCR发生相关。.本研究将阐述MEG3通过miR-770-5p调控下游靶基因SRGAP1的表达，影响ENCCs迁移和增殖，探讨该通路在HSCR发生中的作用，为HSCR的病因学研究提供新的视角。

肠神经嵴细胞（ENCCs）迁移和增殖障碍是先天性巨结肠（HSCR）发生的主要原因，但其具体机制尚不明确，本课题主要研究lncRNA及miRNA在先天性巨结肠中的作用机制。.实验组采用lncRNA芯片筛选HSCR病变段差异表lncRNA时发现lncRNA-MEG3显著低表达，其内含子区编码进化上高度保守的miR-770-5p，生物信息预测SRGAP1是miR-770-5p的靶基因。人群验证发现lncRNA-MEG3、miR-770-5p在HSCR病变段一致低表达，SRGAP1高表达。体外实验提示低表达lncRNA-MEG3、miR-770-5p抑制神经细胞迁移增殖功能，而低表达SRGAP1可以扭转lncRNA-MEG3、miR-770-5p导致的迁移增殖障碍，提示MEG3/miR-770-5p/SRGAP1通路参与先天性巨结肠的发生。.本研究首次阐述lncRNA-MEG3及其内含子miR-770-5p在先天性巨结肠发生中影响神经嵴细胞迁移和增殖功能，不仅可以为先天性巨结肠的发生机制的研究提供新的观点，同时也为体内神经嵴细胞迁移、增殖功能障碍的早期干预寻找治疗靶点，为胚胎期先天性巨结肠的防治提供理论依据。