HCN4基因变异介导心肌细胞钙稳态失衡在SUNDS中的致病作用机制研究

SUNDS是主要发生于平素体健的青壮年男性的睡眠中猝死现象，通过系统尸体解剖、组织病理学检查等检验分析不能明确死亡原因，明确死因在疑似SUNDS的案件调查中具有十分重要的法医学意义。遗传性致死性心律失常可能在SUNDS的发生中发挥了重要作用，但心律失常引起猝死的具体机制和心律失常相关基因或蛋白尚未完全明确。HCN4基因的正常表达和功能调控对心脏自主节律的产生和维持具有重要作用，其表达和功能失衡可能导致心律失常和猝死发生。本课题拟在SUNDS病例中展开HCN4基因变异筛查，明确SUNDS病例中HCN4基因变异的分子病理学特征，并通过RT-qPCR、Western Blotting、膜片钳检测、免疫共沉淀实验等实验技术，从mRNA、蛋白、细胞电生理等多个层次全面分析HCN4基因变异对HCN4蛋白表达和通道电流的影响及机制，为SUNDS的早期筛查和临床防治提供科学依据。

SUNDS is a sudden death mainly occurs in young men during sleep. The cause of death of SUNDS could not be determined by systematic autopsy and histopathological examination. It is of great forensic significance to clarify the cause of death in the investigation of suspected SUNDS cases. Hereditary fatal arrhythmias may takes an important part in the occurrence of SUNDS. However, the specific mechanism of death and arrhythmia related genes or proteins have not been fully identified in SUNDS. The normal expression and functional regulation of HCN4 gene plays an important role in the production and maintenance of cardiac autonomic rhythm, while imbalanced expression and dysfunction of HCN4 protein may induce arrhythmias and related sudden death. In this project, we intend to screen the variation of HCN4 gene in SUNDS, thus to identify the molecular pathological characteristics of HCN4 gene variation in SUNDS, and RT-qPCR, Western blotting, whole cell patch clamp detection, CO-IP experiment are applied to analyze the effect and mechanism of HCN4 gene variation on HCN4 protein expression and channel current at levels of mRNA, protein and cell electrophysiology. We aim to reveal the molecular biology and cellular electrophysiological mechanism of HCN4 gene variation in the development of hereditary arrhythmia and SUNDS, thus to provide scientific evidence for early screening and clinical prevention of SUNDS.