The Institute of Cardiovascular Diseases & Department of Cardiovascular Surgery, TEDA International Cardiovascular Hospital, Tianjin University & Chinese Academy of Medical Sciences, Tianjin, People's Republic of China.
Drug Research and Development Center, Wannan Medical College, Wuhu, People's Republic of China.
Am J Physiol Cell Physiol. 2021 Sep 1;321(3):C443-C452. doi: 10.1152/ajpcell.00167.2021. Epub 2021 Jul 14.
Ventricular septal defects (VSDs) are the most common congenital heart defects (CHDs). Studies have documented that has a crucial impact on cardiac growth, but the role of variants in the gene promoter in patients with VSD has not been explored. In 400 subjects (200 patients with isolated and sporadic VSDs: 200 healthy controls), we investigated the gene promoter variant and performed cellular functional experiments by using the dual-luciferase reporter assay to verify the impact on gene expression. In the promoter, five variants were found only in patients with VSD by sequencing. Cellular functional experiments demonstrated that three variants decreased the transcriptional activity of the promoter ( < 0.05). Further analysis with the online JASPAR database demonstrated that a cluster of putative binding sites for transcription factors may be altered by these variants, possibly resulting in change of ISL1 protein expression and VSD formation. Our study has, for the first time, identified novel variants in the gene promoter region in the Han Chinese patients with isolated and sporadic VSD. In addition, the cellular functional experiments, electrophoretic mobility shift assay, and bioinformatic analysis have demonstrated that these variants significantly alter the expression of the gene and affect the binding of transcription factors, likely resulting in VSD. Therefore, this study may provide new insights into the role of the gene promoter region for a better understanding of genetic basis of the formation of CHDs and may promote further investigations on mechanism of the formation of CHDs.
室间隔缺损（VSD）是最常见的先天性心脏病（CHD）。研究表明，ISL1 对心脏生长有重要影响，但 VSD 患者中 基因启动子的变异体的作用尚未得到探索。在 400 名受试者（200 名患有孤立性和散发性 VSD 的患者：200 名健康对照者）中，我们通过双荧光素酶报告基因检测法研究了 基因启动子变异体，并进行了细胞功能实验，以验证对基因表达的影响。在 基因启动子中，通过测序仅在 VSD 患者中发现了 5 个变异体。细胞功能实验表明，有 3 个变异体降低了 基因启动子的转录活性（<0.05）。通过在线 JASPAR 数据库的进一步分析表明，这些变异体可能改变了转录因子的潜在结合位点簇，可能导致 ISL1 蛋白表达和 VSD 形成的改变。本研究首次在汉族孤立性和散发性 VSD 患者的 基因启动子区鉴定出了新的变异体。此外，细胞功能实验、电泳迁移率变动分析和生物信息学分析表明，这些变异体显著改变了 基因的表达，并影响了转录因子的结合，可能导致 VSD。因此，这项研究可能为更好地理解 CHD 形成的遗传基础提供了对基因启动子区域作用的新见解，并可能促进对 CHD 形成机制的进一步研究。
