BAF200 is required for heart morphogenesis and coronary artery development.

Lingjuan He,Libo Zhang,Xueying Tian,Zhong Wang,Hui Zhang,Bin Zhou,Xiuzhen Huang,Tianyuan Hu,Li Chen

doi:10.1371/journal.pone.0109493

Abstract

ATP-dependent SWI/SNF chromatin remodeling complexes utilize ATP hydrolysis to non-covalently change nucleosome-DNA interactions and are essential in stem cell development, organogenesis, and tumorigenesis. Biochemical studies show that SWI/SNF in mammalian cells can be divided into two subcomplexes BAF and PBAF based on the subunit composition. ARID2 or BAF200 has been defined as an intrinsic subunit of PBAF complex. However, the function of BAF200 in vivo is not clear. To dissect the possible role of BAF200 in regulating embryogenesis and organ development, we generated BAF200 mutant mice and found they were embryonic lethal. BAF200 mutant embryos exhibited multiple cardiac defects including thin myocardium, ventricular septum defect, common atrioventricular valve, and double outlet right ventricle around E14.5. Moreover, we also detected reduced intramyocardial coronary arteries in BAF200 mutants, suggesting that BAF200 is required for proper migration and differentiation of subepicardial venous cells into arterial endothelial cells. Our work revealed that PBAF complex plays a critical role in heart morphogenesis and coronary artery angiogenesis.

Highlights

Epigenetic regulation of embryonic development involves DNA methylation, histone modifications and ATP-dependent chromatin remodeling [1]
Our previous studies have shown that BAF-specific BAF250 knockout mouse embryos die early around implantation and are defective in mesodermal differentiation [11], whereas PBAFspecific BAF180 deficiency in mouse embryos leads to severe hypoplastic ventricle development and trophoblast placental defects [12], and defect in coronary vessel formation [13]
We measured the remaining Baf200 transcripts in BAF200LacZ/LacZ mutant embryonic samples by quantitative reverse transcriptase-polymerase chain reaction, and found significant reduction of Baf200 RNA expression in mutants compared with littermate controls (Fig. 1B)

Summary

Introduction

Epigenetic regulation of embryonic development involves DNA methylation, histone modifications and ATP-dependent chromatin remodeling [1]. For section x-gal staining, embryos and hearts were collected in PBS on ice and fixed in 4% paraformaldehyde at 4uC for 1 hour. Embryos were incubated in block solution containing PECAM antibody (BD PHharmingen, 553370) overnight at 4uC, followed by five times wash in PBS.

Results

Conclusion