The Effect of Zinc Finger Domain Protein Spalt Like Transcription Factor 4 (SALL4A)-Mediated DNA Demethylation on Cardiac Development and Function

Abstract

SALL4 is one of the important members of SALL4 gene family and participates in embryo development, including organogenesis, maintenance and reconstruction of pluripotency, such as heart development and function. This study explores the effects of SALL4A-mediated DNA demethylation on heart development and function. The ventricular weight/body weight, ventricular diameter, septal thickness, LVEF% and LVFS% of the SALL4A gene knockout and normal SD mice were compared. ChIP/DIP-Seq and RNA-Seq technology were used to assess the mechanism by how SALL4Adependent DNA demethylation affects heart development and function. We found that compared with control group of SD mice, the ventricular weight/body weight of SD mice in SALL4A knockout group was significantly lower. In addition, SALL4A knockout group showed significantly lower interval thickness, LVEF%, LVFS% and other indicators related to heart development than normal SD mice. In addition, SALL4A-mediated DNA demethylation was closely related to TET. Both TET1 and TET2 were enriched in the SALL4A binding site. SALL4A targeted 5hmC gene in vitro and occupied the enhancer in mouse embryonic stem cells (ESCs) to promote 5hmC oxidation depending on TET enzyme. Therefore, SALL4A promoted oxidation of 5hmC and caused DNA demethylation which finally affected heart development and function. In conclusion, SALL4A, as a gene that can target and bind 5hmC, promotes the oxidation of 5hmC by stabilizing TET enzyme binding, thereby regulating the DNA demethylation process in ESCs to further regulate heart development and function.