孕期高脂饮食可致子代糖脂代谢异常，但机制尚不明确。我们前期研究发现，孕期高脂导致的子代下丘脑胰淀素（Amylin）抵抗可能与m6A阅读器IGF2BP1介导的Amylin受体调节蛋白Ramp3 mRNA m6A低甲基化有关。为探究孕期高脂条件下m6A修饰在下子代下丘脑Amylin抵抗中的作用及其对下丘脑神经分化的影响，本项目拟通过MeRIP-seq明确孕期高脂导致子代下丘脑Ramp3 mRNA低甲基化区域，利用RNA降解实验、免疫荧光、荧光原位杂交等技术明确IGF2BP1介导的Ramp3 m6A修饰在维持其mRNA稳定性中的作用，及其对Amylin受体后信号通路、下丘脑神经分化的影响。进一步运用脑定位注射技术构建下丘脑IGF2BP1过表达小鼠模型，验证IGF2BP1介导的Ramp3 m6A修饰对高脂所致子代下丘脑神经分化及代谢异常的纠正作用，从而揭示高脂诱发胎源性代谢异常的表观调控新机制。

Maternal high-fat diet during pregnancy can cause glucose and lipid metabolic disorders, but the underlying mechanism remains unclear. Our previous study has found that hypothalamic amylin resistance in response to maternal high-fat diet during pregnancy is associated with the IGF2BP1-mediated decreased m6A peaks in Ramp3 mRNA, which encodes the amylin receptor activity modifying protein. In this project, we aim to further explore the role of m6A modification in hypothalamic amylin resistance and its effect on hypothalamic neural differentiation in offspring exposed to maternal high-fat diet. We will first investigate the specific locus of m6A modifications in Ramp3 mRNA in offspring’s hypothalamus in response to maternal high-fat diet by using MeRIP-seq. Then the influence of IGF2BP1-mediated decreased m6A levels in Ramp3 mRNA on Ramp3 mRNA stability, post-receptor signaling pathways of amylin, and amylin-induced hypothalamic neural differentiation will be detected by molecular techniques including RNA decay assay, immunofluorescence, fluorescence in situ hybridization, etc. Furthermore, mice that specifically overexpress IGF2BP1will be generated by brain localization injection technique, and will be used to validate the rescue effects of IGF2BP1-induced m6A modification in Ramp3 mRNA on the impairment of hypothalamic neural differentiation and the abnormal glucose and lipid metabolism in offspring exposed to maternal high-fat diet. This project is expected to provide novel insights into how epigenetic modifications regulate maternal high-fat diet related fetal-original metabolic diseases.