Cardiac transcription factors are master regulators during heart development. Some were shown to transdifferentiate tail tip and cardiac fibroblasts into cardiomyocytes. However, recent studies have showed that controversies exist. Potential difference in tail tip and cardiac fibroblast isolation may possibly confound the observations. Moreover, due to the use of a cardiac reporter (Myh6) selec...

The noncoding genome is pervasively transcribed. Noncoding RNAs (ncRNAs) generated from enhancers have been proposed as a general facet of enhancer function and some have been shown to be required for enhancer activity. Here we examine the transcription-factor-(TF)-dependence of ncRNA expression to define enhancers and enhancer-associated ncRNAs that are involved in a TF-dependent regulatory ne...

tbx5, a member of the T-box gene family, encodes one of the key transcription factors mediating vertebrate heart development. Tbx5 function in heart development appears to be exquisitely sensitive to gene dosage, since both haploinsufficiency and gene duplication generate the cardiac abnormalities associated with Holt-Oram syndrome (HOS), a highly penetrant autosomal dominant disease characteri...

Myocardial differentiation is associated with the activation and expression of an array of cardiac specific genes. However, the transcriptional networks that control cardiac gene expression are not completely understood. Myocardin is a cardiac and smooth muscle-specific expressed transcriptional coactivator of Serum Response Factor (SRF) and is able to potently activate cardiac and smooth muscl...

TBX5 is a T-box transcriptional factor required for cardiogenesis and limb development. TBX5 mutations cause Holt-Oram syndrome characterized by congenital heart defects and upper limb deformations. Here we establish a novel function for TBX5 in pre-mRNA splicing, and we show that this function is relevant to the pathogenesis of Holt-Oram syndrome, providing a novel pathogenic mechanism for the...

RATIONALE Holt-Oram syndrome is an autosomal dominant heart-hand syndrome caused by mutations in the TBX5 gene. Overexpression of Tbx5 in the chick proepicardial organ impaired coronary blood vessel formation. However, the potential activity of Tbx5 in the epicardium itself, and the role of Tbx5 in mammalian coronary vasculogenesis, remains largely unknown. OBJECTIVE To evaluate the consequen...

In humans, septal defects are among the most prevalent congenital heart diseases, but their cellular and molecular origins are not fully understood. We report that transcription factor Tbx5 is present in a subpopulation of endocardial cells and that its deletion therein results in fully penetrant, dose-dependent atrial septal defects in mice. Increased apoptosis of endocardial cells lacking Tbx...

In this study, we analyzed the methylation status of human promoters in rheumatoid arthritis synovial fibroblasts (RASF). Differentially methylated genes between RASF and osteoarthritis synovial fibroblasts (OASF) were identified by methylated DNA immunoprecipitation and hybridization to human promoter tiling arrays. The methylation status was confirmed by pyrosequencing. Gene and protein expre...

Extensive misexpression studies were carried out to explore the roles played by Tbx5, the expression of which is excluded from the right ventricle (RV) during cardiogenesis. When Tbx5 was misexpressed ubiquitously, ventricular septum was not formed, resulting in a single ventricle. In such heart, left ventricle (LV)-specific ANF gene was induced. In search of the putative RV factor(s), we have ...