Cardiovascular Division, Department of Medicine, University of Minnesota, 401 East River ParkwayVCRC 1st Floor, Suite 131 Minneapolis, MN 55455, USA.
Department of Physiology, Basic Medical College, Nanchang University, Nanchang, Jiangxi 330006, China.
Cardiovasc Res. 2023 Jul 6;119(8):1728-1739. doi: 10.1093/cvr/cvad054.
Congenital heart disease (CHD) is the most common genetic birth defect, which has considerable morbidity and mortality. We focused on deciphering key regulators that govern cardiac progenitors and cardiogenesis. FOXK1 is a forkhead/winged helix transcription factor known to regulate cell cycle kinetics and is restricted to mesodermal progenitors, somites, and heart. In the present study, we define an essential role for FOXK1 during cardiovascular development.
We used the mouse embryoid body system to differentiate control and Foxk1 KO embryonic stem cells into mesodermal, cardiac progenitor cells and mature cardiac cells. Using flow cytometry, immunohistochemistry, cardiac beating, transcriptional and chromatin immunoprecipitation quantitative polymerase chain reaction assays, bulk RNA sequencing (RNAseq) and assay for transposase-accessible chromatin using sequencing (ATACseq) analyses, FOXK1 was observed to be an important regulator of cardiogenesis. Flow cytometry analyses revealed perturbed cardiogenesis in Foxk1 KO embryoid bodies (EBs). Bulk RNAseq analysis at two developmental stages showed a significant reduction of the cardiac molecular program in Foxk1 KO EBs compared to the control EBs. ATACseq analysis during EB differentiation demonstrated that the chromatin landscape nearby known important regulators of cardiogenesis was significantly relaxed in control EBs compared to Foxk1 KO EBs. Furthermore, we demonstrated that in the absence of FOXK1, cardiac differentiation was markedly impaired by assaying for cardiac Troponin T expression and cardiac contractility. We demonstrate that FOXK1 is an important regulator of cardiogenesis by repressing the Wnt/β-catenin signalling pathway and thereby promoting differentiation.
These results identify FOXK1 as an essential transcriptional and epigenetic regulator of cardiovascular development. Mechanistically, FOXK1 represses Wnt signalling to promote the development of cardiac progenitor cells.
先天性心脏病（CHD）是最常见的遗传出生缺陷，具有相当高的发病率和死亡率。我们专注于破译控制心脏祖细胞和心脏发生的关键调节因子。FOXK1 是一种已知调节细胞周期动力学的叉头/翼状螺旋转录因子，局限于中胚层祖细胞、体节和心脏。在本研究中，我们定义了 FOXK1 在心血管发育过程中的重要作用。
我们使用小鼠胚状体系统将对照和 Foxk1 KO 胚胎干细胞分化为中胚层、心脏祖细胞和成熟的心脏细胞。使用流式细胞术、免疫组织化学、心脏跳动、转录和染色质免疫沉淀定量聚合酶链反应分析、批量 RNA 测序（RNAseq）和转座酶可及染色质测序（ATACseq）分析，观察到 FOXK1 是心脏发生的重要调节因子。流式细胞术分析显示 Foxk1 KO 胚状体（EB）的心脏发生受到干扰。在两个发育阶段的批量 RNAseq 分析显示，与对照 EB 相比，Foxk1 KO EB 中心脏分子程序显著减少。EB 分化过程中的 ATACseq 分析表明，在对照 EB 中，与 Foxk1 KO EB 相比，已知心脏发生重要调节因子附近的染色质景观明显放松。此外，我们通过检测心脏肌钙蛋白 T 表达和心脏收缩性来证明，在缺乏 FOXK1 的情况下，心脏分化明显受损。我们通过抑制 Wnt/β-catenin 信号通路并促进分化来证明 FOXK1 是心脏发生的重要调节因子。
这些结果表明 FOXK1 是心血管发育的重要转录和表观遗传调节因子。从机制上讲，FOXK1 抑制 Wnt 信号以促进心脏祖细胞的发育。
