甲基化转移酶样蛋白3介导的m6A修饰参与高静水压诱导的心房肌细胞电重塑  

METTL3-mediated m6A modification involved in electrical remodeling of atrial cardiomyocytes under high hydrostatic pressure

作　　者：刘攀月 曾珑 肖海茵 肖菲菲 朱蕊 杨慧[2] 邝素娟[2] 邓春玉[2] 饶芳[2] 魏薇[2] LIU Pan-yue;ZENG Long;XIAO Hai-yin;XIAO Fei-fei;ZHU Rui;YANG Hui;KUANG Su-juan;DENG Chun-yu;RAO Fang;WEI Wei(School of Medicine,South China University of Technology,Guangzhou 510006,China;Dept of Cardiology,Guangdong Cardiovascular Institute,Guangdong Provincial People′s Hospital Medical Research Center,Guangdong Academy of Medical Sciences,Guangzhou 510080,China)

机构地区：[1]华南理工大学医学院,广东广州510006 [2]广东省心血管病研究所心内科,广东省人民医院,广东省医学科学院,广东广州510080

出　　处：《中国药理学通报》2023年第12期2258-2265,共8页Chinese Pharmacological Bulletin

基　　金：国家自然科学基金青年科学基金项目(No 81900301)。

摘　　要：目的探讨甲基化转移酶样蛋白3(methyltransferase-like protein 3,METTL3)介导的N-6甲基腺苷(N6-methyladenosine,m6A)修饰对高静水压下心房肌细胞L型钙通道的调控作用。方法C57BL/6J小鼠随机分为对照组和高血压组(血管紧张素持续给药4周)。采用Masson染色观察小鼠心房组织纤维化情况,斑点印迹实验检测小鼠心房组织中m6A,Western blot检测METTL3和Cav1.2表达情况。体外培养的小鼠心房细胞株HL-1细胞,予加压构建高静水压模型及干预METTL3,观察细胞中m6A表达含量、METTL3和Cav1.2水平的改变,全细胞膜片钳检测HL-1动作电位时程(action potential duration,APD)及L型钙电流(L-type calcium current,I Ca,L)。结果与对照组相比,高血压组小鼠心房肌细胞形态紊乱,间质纤维化增加,且心房组织中m6A含量及METTL3表达水平也明显增加,离子通道蛋白Cav1.2表达减少。体外培养的HL-1细胞,施予不同静水压(0、20、40 mmHg)干预后,随着静水压的升高,细胞中m6A、METTL3上调,Cav1.2下调。STM2457(特异性METTL3抑制剂)和si-METTL3可逆转上述变化,同时STM2457逆转高静水压所致的HL-1细胞的APD缩短和I Ca,L峰值密度降低,METTL3可直接与CACNA1C(Cav1.2 mRNA)发生结合。结论高静水压下METTL3介导的m6A修饰可直接调控CACNA1C参与心房肌细胞电重塑。Aim To investigate the regulation of N6-methyladenosine(m6A)modification on L-type calcium channels in atrial myocytes under high hydrostatic pressure,mediated by methyltransferase-like protein 3(METTL3).Methods C57BL/6J mice were randomly assigned to the control group and the hypertension group(treated with continuous administration of angiotensin for four weeks).Masson staining was used to observe the fibrosis of mouse atrial tissue,while dot blot assay and Western blot were used to detect the levels of m6A,METTL3,and Cav1.2 in the atrial tissue.A high hydrostatic pressure model was constructed using the HL-1 cell line cultured in vitro,and METTL3 was intervened to observe changes in m6A expression levels,METTL3 and Cav1.2 levels in cells,and action potential duration(APD)and L-type calcium current(I Ca,L)were detected using whole-cell patch clamp.Results Compared to the control group,the hypertension group showed disordered atrial myocyte morphology,increased interstitial fibrosis,significant increased m6A content and METTL3 expression levels in the atrial tissue,and decreased expression of ion channel protein Cav1.2.In HL-1 cells cultured in vitro,increasing hydrostatic pressure(0,20,40 mmHg)up-regulated m6A and METTL3 expression levels,down-regulated Cav1.2,and these changes were reversed with STM2457 and si-METTL3.Furthermore,specific METTL3 inhibitor STM2457 reversed the shortening of APD and the decrease of I Ca,L peak density in HL-1 cells caused by high hydrostatic pressure,while METTL3 directly bound to CACNA1C.Conclusion METTL3-mediated m6A modification might directly regulate CACNA1C to participate in electrical remodeling of atrial myocytes under high hydrostatic pressure.

关 键 词：METTL3 高静水压 m6A L型钙通道 心房电重塑 房颤 

分 类 号：R-332[医药卫生] R329.24R329.411R541.75R544.1