Abstract
Abstract in English, Chinese Neural tube defects (NTDs) are severe congenital neurodevelopmental disorders arising from incomplete neural tube closure. Although folate supplementation has been shown to mitigate the incidence of NTDs, some cases, often attributable to genetic factors, remain unpreventable. The SHROOM3 gene has been implicated in NTD cases that are unresponsive to folate supplementation; at present, however, the underlying mechanism remains unclear. Neural tube morphogenesis is a complex process involving the folding of the planar epithelium of the neural plate. To determine the role of SHROOM3 in early developmental morphogenesis, we established a neuroepithelial organoid culture system derived from cynomolgus monkeys to closely mimic the in vivo neural plate phase. Loss of SHROOM3 resulted in shorter neuroepithelial cells and smaller nuclei. These morphological changes were attributed to the insufficient recruitment of cytoskeletal proteins, namely fibrous actin (F-actin), myosin II, and phospho-myosin light chain (PMLC), to the apical side of the neuroepithelial cells. Notably, these defects were not rescued by folate supplementation. RNA sequencing revealed that differentially expressed genes were enriched in biological processes associated with cellular and organ morphogenesis. In summary, we established an authentic in vitro system to study NTDs and identified a novel mechanism for NTDs that are unresponsive to folate supplementation. 神经管闭合缺陷（NTDs）是由神经管闭合失败引起的严重先天性神经发育疾病。虽然补充叶酸可以减少NTDs的发生，但仍有一些遗传因素导致的NTDs无法被预防。其中， SHROOM3基因突变导致的NTDs无法通过补充叶酸被预防，并且致病机制尚不清楚。神经管闭合伴有上皮细胞的形变和神经板的会聚延伸，这是一个复杂的形态发生过程。为了了解 SHROOM3在发育早期阶段是否在形态发生中起重要作用，我们建立了一种食蟹猴的神经上皮类器官培养体系来模拟体内神经板发育阶段。我们发现SHROOM3的缺失导致神经上皮细胞变短，细胞核变小。这些形态变化是由于肌动蛋白F-actin、肌球蛋白 Myosin II 和磷酸化肌球轻链蛋白PMLC未能被募集到神经上皮细胞的顶端造成。这种现象不能通过补充叶酸来挽救。RNA-seq数据显示，差异基因在细胞的形态发生和器官形成的通路中高度富集。综上所述，我们建立了一个更真实的体外类器官培养体系来研究NTDs，并揭示了一种补充叶酸无法预防NTDs的新机制。.