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The transition of mouse embryonic stem cells (ESCs) between serum/LIF and 2i(MEK and GSK3 kinase inhibitor)/LIF culture conditions serves as a valuable model for exploring the mechanisms underlying ground and confused pluripotent states. Regulatory networks comprising core and ancillary pluripotency factors drive the gene expression programs defining stable naïve pluripotency. In our study, we systematically screened factors essential for ESC pluripotency, identifying TEAD2 as an ancillary factor maintaining ground-state pluripotency in 2i/LIF ESCs and facilitating the transition from serum/LIF to 2i/LIF ESCs. TEAD2 exhibits increased binding to chromatin in 2i/LIF ESCs, targeting active chromatin regions to regulate the expression of 2i-specific genes. In addition, TEAD2 facilitates the expression of 2i-specific genes by mediating enhancer-promoter interactions during the serum/LIF to 2i/LIF transition. Notably, deletion of Tead2 results in reduction of a specific set of enhancer-promoter interactions without significantly affecting binding of chromatin architecture proteins, CCCTC-binding factor (CTCF), and Yin Yang 1 (YY1). In summary, our findings highlight a novel prominent role of TEAD2 in orchestrating higher-order chromatin structures of 2i-specific genes to sustain ground-state pluripotency. Synopsis: The transition of mouse embryonic stem cells (ESCs) between ground and confused state culture conditions unveils transcriptional networks governing pluripotency. In this study, we identified TEAD2 as a key ESC regulator initiating pluripotency through mediating 2i (MEK and GSK3 kinase inhibitor) state-specific chromatin looping and genome architecture. TEAD2 supports the ground-state of pluripotency and facilitates the conversion from serum/LIF to 2i/LIF ESCs. Genome-wide TEAD2 occupancy is increased in 2i/LIF ESCs, targeting active chromatin regions at 2i-specific genes. TEAD2 promotes 2i-specific gene expression by mediating enhancer-promoter interactions. Mutation of TEAD2 binding sites at B4galt6 promoter disrupts enhancer-promoter interactions at this 2i-specific gene locus. The transcription factor TEAD2 aids naïve pluripotency of mouse embryonic stem cells by orchestrating state-specific genome architecture. [ABSTRACT FROM AUTHOR]

Background: Four transcription factors, Oct4, Sox2, Klf4, and c-Myc (the Yamanka factors), can reprogram somatic cells to induced pluripotent stem cells (iPSCs). Many studies have provided a number of alternative combinations to the non-Yamanaka factors. However, it is clear that many additional transcription factors that can generate iPSCs remain to be discovered. Methods: The chromatin accessibility and transcriptional level of human embryonic stem cells and human urine cells were compared by Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq) and RNA sequencing (RNA-seq) to identify potential reprogramming factors. Selected transcription factors were employed to reprogram urine cells, and the reprogramming efficiency was measured. Urine-derived iPSCs were detected for pluripotency by Immunofluorescence, quantitative polymerase chain reaction, RNA sequencing and teratoma formation test. Finally, we assessed the differentiation potential of the new iPSCs to cardiomyocytes in vitro. Results: ATAC-seq and RNA-seq datasets predicted TEAD2, TEAD4 and ZIC3 as potential factors involved in urine cell reprogramming. Transfection of TEAD2, TEAD4 and ZIC3 (in the presence of Yamanaka factors) significantly improved the reprogramming efficiency of urine cells. We confirmed that the newly generated iPSCs possessed pluripotency characteristics similar to normal H1 embryonic stem cells. We also confirmed that the new iPSCs could differentiate to functional cardiomyocytes. Conclusions: In conclusion, TEAD2, TEAD4 and ZIC3 can increase the efficiency of reprogramming human urine cells into iPSCs, and provides a new stem cell sources for the clinical application and modeling of cardiovascular disease. [ABSTRACT FROM AUTHOR]

Acetyl-coenzyme A (acetyl-CoA) plays an important role in metabolism, gene expression, signaling, and other cellular processes via transfer of its acetyl group to proteins and metabolites. However, the synthesis and usage of acetyl-CoA in disease states such as cancer are poorly characterized. Here, we investigated global acetyl-CoA synthesis and protein acetylation in a mouse model and patient samples of hepatocellular carcinoma (HCC). Unexpectedly, we found that acetyl-CoA levels are decreased in HCC due to transcriptional downregulation of all six acetyl-CoA biosynthesis pathways. This led to hypo-acetylation specifically of non-histone proteins, including many enzymes in metabolic pathways. Importantly, repression of acetyl-CoA synthesis promoted oncogenic dedifferentiation and proliferation. Mechanistically, acetyl-CoA synthesis was repressed by the transcription factors TEAD2 and E2A, previously unknown to control acetyl-CoA synthesis. Knockdown of TEAD2 and E2A restored acetyl-CoA levels and inhibited tumor growth. Our findings causally link transcriptional reprogramming of acetyl-CoA metabolism, dedifferentiation, and cancer. [Display omitted] • Acetyl-CoA levels and non-histone protein acetylation are decreased in HCC • All six acetyl-CoA synthesis pathways are transcriptionally downregulated in HCC • Acetyl-CoA synthesis genes are globally repressed by transcription factors TEAD2 and E2A • TEAD2 and E2A promote proliferation and dedifferentiation by reducing acetyl-CoA levels Park et al. demonstrate that TEAD2 and E2A transcriptionally repress acetyl-CoA synthesis in HCC, which results in reduced acetylation specifically of non-histone proteins. The authors show that repression of acetyl-CoA synthesis, in turn, promotes oncogenic dedifferentiation and proliferation. [ABSTRACT FROM AUTHOR]

Pax3 is a transcription factor that is required by Pre-migratory neural crest cells give rise to the peripheral nervous system, melanocytes, some vascular smooth muscle, and numerous other derivatives. These cells require the transcription factor Pax3, and both mice and humans with Pax3 deficiency exhibit neural crest-related developmental defects. Pax3 is also expressed in the dorsal neural tube, and by myogenic progenitors in the presomitic mesoderm and the hypaxial somites. Molecular pathways that regulate Pax3 expression in the roof plate probably represent early upstream signals in neural crest induction. We have identified an enhancer region in the Pax3 genomic locus that is sufficient to recapitulate expression in neural crest precursors in transgenic mice. We show that Tead2, a member of the Tead box family of transcription factors, binds to a neural crest enhancer and activates Pax3 expression. Tead2, and its co-activator YAP65, are co-expressed with Pax3 in the dorsal neural tube, and mutation of the Tead2 binding site in the context of Pax3 transgenic constructs abolishes neural expression. In addition, a Tead2-Engrailed fusion protein is able to repress retinoic acid-induced Pax3 expression in P19 cells and in vivo. These results suggest that Tead2 is an endogenous activator of Pax3 in neural crest. [ABSTRACT FROM AUTHOR]

In the context of mechanically induced force transmission, the modification of the actin cytoskeleton through involvement of zyxin is an established concept. However, in cells of the periodontal ligament (PDL), which is physiologically subjected to intermittent mechanical forces, the force-responsive modulation of zyxin and the molecular key players, which orchestrate its cellular regulation, have not yet been elucidated. By employing indirect immunofluorescence and western blotting with different subcellular fractions, we show here in stretch force-exposed human PDL fibroblasts (hPDLFs) that (i) the zyxin protein is modulated, and (ii) its subcellular localization is altered. More importantly, using a pharmacological intervention approach, to inhibit the nuclear presence of the co-transcriptional activator yes-associated protein (YAP), we evidence for the first time that on the molecular level, the cellular abundance of zyxin, among the Thyrotrophic Embryonic Factor (TEF)-binding proteins, is regulated by YAP rather than TAZ. Our findings provide novel insights into the topic how cells of the periodontium and the periodontal ligament in particular respond and may adapt to mechanical forces, and first time identify YAP as the key player of the intracellular regulation of the mechano-sensor and mechano-transducer zyxin in hPDLFs. Moreover, the findings broaden the current knowledge on YAP, since so far, currently only very few YAP-regulated genes have been identified. • YAP is the key player of the intracellular regulation of the mechano-sensor zyxin in hPDLFs. • Zyxin is regulated by the TEF binding protein YAP rather than TAZ in hPDLFs. • Strain modulates TEF-family member TEAD2, binding partner YAP and the 14-3-3 protein. • Verteporfin treatment suggest that YAP nuclear depletion is involved in the causation of zyxin diminishment. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "TEAD2, a Hippo pathway gene, is somatically mutated in gastric and colorectal cancers with high microsatellite instability."