YTHDF1介导circ-Nf1的m6A甲基化修饰促进beta-arrestin2向膜上转运参与吗啡耐受的机制研究

吗啡耐受限制其应用，机制不清。CircRNA的m6A修饰调控机体多种功能。我们发现吗啡耐受的大鼠脊髓背角circ-Nf1的m6A修饰显著上调，circ-Nf1总量不变，抑制circ-Nf1或circ-Nf1的甲基化缓解吗啡耐受。吗啡耐受中YTHDF1与circ-Nf1结合增加，抑制METTL14使二者结合减少，缓解吗啡耐受。CircRNA能吸附miRNA发挥功能。YTHDF1与circ-Nf1的结合增强了circ-Nf1吸附miRNA的能力，上调靶蛋白b-arrestin2和AKAP150表达，AKAP150促进b-arrestin2向膜上转运介导吗啡耐受。本项目探讨：①circ-Nf1的m6A修饰通过结合YTHDF1增强了circ-Nf1吸附miRNA的能力参与吗啡耐受的作用机制；②AKAP150促进b-arrestin2向膜上转运介导吗啡耐受的分子机制。该研究能够为解决吗啡耐受提供靶点

The mechanism of morphine tolerance remains unclear. N6-methyladenosine (m6A) modification of RNA is very important for physiological function. Our preliminary experiments showed m6A modification of circ-Nf1 significantly increased in a rat morphine tolerance model, accompanied by an increase in methyltransferase METTL3 and METTL14. Intrathecal injection circ-Nf1siRNA, or METTL14 siRNA significantly attenuated morphine tolerance. RNA pulldown and mass spectrometry analysis showed that the methylation “reader” protein, YTHDF1, was bound with circ-Nf1. Morphine tolerance induced an up-regulated expression of YTHDF1 and a combination of YTHDF1 and circ-Nf1. Intrathecal injection of YTHDF1 siRNA attenuated morphine tolerance. CircRNA can sponge to miRNAs. Overexpression of YTHDF1 enhanced circ-Nf1’s sponging ability of miRNA and increased the expression of miRNA target proteins of beta-arrestin2 and AKAP150. AKAP150 promotes membrane trafficking of beta-arrestin2 and mediates morphine tolerance. This study aims to: (1) clarify the YTHDF1’s mechanism in mediating m6A modification of circ-Nf1 and enhancing thecirc-Nf1’s spong effect to miRNAs in morphine tolerance; (2) explore AKAP150’s mechanism in promoting membrane trafficking of beta-arrestin2 and how it transfers to the cell membrane in relation to morphine tolerance. Our research will provide a novel target for morphine tolerance.