DNA methylation status of TBX20 in patients with tetralogy of Fallot

• Published in: BMC medical genomics Vol. 12; no. 1; p. 75
• Main Authors: Gong, Juan, Sheng, Wei, Ma, Duan, Huang, Guoying, Liu, Fang
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 28-05-2019; BioMed Central; BMC
• Subjects: Anopheles; Base Sequence; Binding Sites; Cardiovascular disease; Care and treatment; Case-Control Studies; Congenital diseases; Congenital heart defects; CpG islands; Defects; Deoxyribonucleic acid; Developmental biology; Diagnosis; DNA; DNA binding proteins; DNA Methylation; DNA sequencing; Electrophoretic mobility; Epigenesis, Genetic; Epigenetic inheritance; Epigenetics; Female; Gene expression; Gene mutation; Genes; Genetic aspects; Genetic research; Heart; HEK293 Cells; Humans; Infant; Journalists; Luciferase; Male; Males; Methylation; Mutation; Pathogenesis; Pulmonary arteries; Sp1 protein; Sp1 transcription factor; Sp1 Transcription Factor - metabolism; Studies; T-Box Domain Proteins - genetics; TBX20 gene; Tetralogy of Fallot; Tetralogy of Fallot - genetics; Transcription factors; Transcription, Genetic - genetics; Ventricle; United States > US; China; Tetralogy of Fallot; DNA methylation; Sp1 transcription factor; TBX20 gene
• ISSN: 1755-8794; 1755-8794
• DOI: 10.1186/s12920-019-0534-3

TBX20 plays an important role in heart development; however, its epigenetic regulation in the pathogenesis of tetralogy of Fallot (TOF) remains unclear.
The methylation levels of the TBX20 promoter region in the right ventricular myocardial tissues of TOF and control samples were measured by the Sequenom MassARRAY platform. Bisulphite-sequencing PCR (BSP) was used to confirm the TBX20 methylation of CpG sites in cells. Dual-luciferase reporter assays were performed to detect the influence of TBX20 methylation and Sp1 transcription factors on gene activity. An electrophoretic mobility shift assay (EMSA) was used to explore the binding of the Sp1 transcription factor to the TBX20 promoter.
TOF cases had a significantly lower TBX20_M1 methylation level than controls (median methylation: 20.40% vs. 38.73%; p = 0.0047). The Sp1 transcription factor, which binds to Sp1 binding sites in the TBX20_M1 region and promotes TBX20 gene activity, was blocked by the methylation of Sp1 binding sites in normal controls. With decreasing methylation in the TOF cases, the Sp1 transcription factor can bind to its binding site within the TBX20 promoter M1 region and promote TBX20 gene expression.
Hypomethylation of the TBX20 promoter region was observed in the TOF cases, and the high expression of the TBX20 gene may be caused by activated Sp1 transcription factor binding because of the decreasing methylation at the Sp1 transcription factor binding sites within TBX20_M1.