lncRNA LINC00881致胎儿生长受限的分子机制研究

LncRNA LINC00881 is a new-found long noncoding RNA through lncRNA microarray,which was lowly expressed in placenta tissue of patients with fetal growth restriction and positively associated with birth weight.Previous studies indicated that knockdown of this gene could increase the apoptosis of trophoblast cells and inhibit the proliferation of trophoblast cells. The mechanism may be associated with recruitment of H3K4 methylase complexes.This study will firstly verify the association of LINC00881 and CCNL1expression in placenta with FGR, and investigate the proliferation and apoptosis level of trophoblast cells in FGR. Moreover, we will investigate the function of LINC00881 in balance of trophoblast cell proliferation and apoptosis by overexpression and knockdown strategies. Further study will userescure strategy, RIP, RNA pull-down etc. To explore the detailed regulatory mechanismof LINC00881 interacted with CCNL1 in the pathogenesis of fetal growth restriction. In-vitro assays would systematically confirm that LINC00881 regulate trophoblast cells proliferation andapoptosis involved in fetal growth restriction effect. There is not any report about LINC00881 in fetal growth restriction, thus, this study is of a certain innovation and will provide a new potential target for the prevention and treatment of FGR.

LINC00881是我们前期应用芯片筛选胎儿生长受限（FGR）与正常对照胎盘组织差异非编码RNA时发现的、差异低表达于FGR胎盘组织、表达水平与新生儿出生体重显著正相关的lncRNA。前期研究发现，沉默LINC00881后人滋养细胞凋亡率显著增高、细胞增殖明显抑制，其机制可能与募集H3K4甲基转移酶复合体调控CCNL1表达有关。本研究拟扩大临床样本，分析LINC00881、CCNL1表达，胎盘滋养细胞增殖凋亡与FGR之间的相关性；采用过表达、敲低、挽救实验策略及RIP、RNA pull-down等技术深入探讨LINC00881通过调控CCNL1表达参与FGR发生的分子机制；并在体论证LINC00881对胎盘滋养细胞增殖、凋亡、FGR发生率的影响。目前尚无LINC00881的报道，本研究将揭示LINC00881在滋养细胞增殖/凋亡平衡中的作用与机制，可为胎儿生长受限的防治提供潜在靶标。

胎儿生长受限（Fetal growth restriction, FGR）又称胎儿宫内发育迟缓，是一种常见的新生儿出生体重异常，我国发生率为6.39%，其死亡率为正常发育儿的6-10倍。FGR对子代近远期健康都会造成不良影响。胎盘发育缺陷或功能障碍往往导致FGR，近年来lncRNA不断被证实在胎盘细胞增殖/凋亡中发挥着重要的调控作用。LINC00881是我们前期通过筛选发现低表达于FGR胎盘组织的lncRNA。我们的研究发现，①过表达LINC00881后，人滋养细胞HTR-8/Svneo增殖和迁移增多，沉默LINC00881后，抑制了HTR-8/Svneo增殖和迁移，并促进细胞的凋亡；②通过RNA pull-down、RIP技术结合生物信息学分析发现CALR、ACTB、PRDX6、ANXA1、PRDX1和FSCN1这六个基因可能是LINC00881下游的靶基因；③qRT-PCR和Western blot结果显示，过表达LINC00881后HTR-8/Svneo细胞中FSCN1表达下调，LINC00881基因下调后，FSCN1基因表达上调；④构建FSCN1过表达质粒和小干扰RNA感染人滋养细胞HTR-8/SVneo，发现干扰FSCN1后抑制HTR-8/SVneo细胞的凋亡并促进其增殖、迁移和侵袭，过表达FSCN1后抑制了HTR-8/SVneo细胞的增殖、迁移和侵袭；⑤挽救实验证明FSCN1过表达可以挽救LINC00881过表达在HTR-8细胞中的作用。以上结果表明：LINC00881与FGR的发生有关，通过调控FSCN1表达参与胎盘滋养细胞增殖/凋亡平衡，调控FGR进展，该研究可能为临床上FGR 防治提供潜在的干预靶标。