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DNA Methyltransferase 3 A (DNMT3A) is an important facilitator of differentiation of both embryonic and hematopoietic stem cells. Heterozygous germline mutations in DNMT3A lead to Tatton-Brown-Rahman Syndrome (TBRS), characterized by obesity and excessive height. While DNMT3A is known to impact feeding behavior via the hypothalamus, here we investigated a role in adipocyte progenitors utilizing heterozygous knockout mice that recapitulate cardinal TBRS phenotypes. These mice become morbidly obese due to adipocyte enlargement and tissue expansion. Adipose tissue in these mice exhibited defects in preadipocyte maturation and precocious activation of inflammatory gene networks, including interleukin-6 signaling. Adipocyte progenitor cell lines lacking DNMT3A exhibited aberrant differentiation. Furthermore, mice in which Dnmt3a was specifically ablated in adipocyte progenitors showed enlarged fat depots and increased progenitor numbers, partly recapitulating the TBRS obesity phenotypes. Loss of DNMT3A led to constitutive DNA hypomethylation, such that the DNA methylation landscape of young adipocyte progenitors resemble that of older wild-type mice. Together, our results demonstrate that DNMT3A coordinates both the central and local control of energy storage required to maintain normal weight and prevent inflammatory obesity.

Abstract Background DNA methylation is a heritable epigenetic mark, enabling stable but reversible gene repression. In mammalian cells, DNA methyltransferases (DNMTs) are responsible for modifying cytosine to 5-methylcytosine (5mC), which can be further oxidized by the TET dioxygenases to ultimately cause DNA demethylation. However, the genome-wide cooperation and functions of these two families of proteins, especially at large under-methylated regions, called canyons, remain largely unknown. Results Here we demonstrate that DNMT3A and TET1 function in a complementary and competitive manner in mouse embryonic stem cells to mediate proper epigenetic landscapes and gene expression. The longer isoform of DNMT3A, DNMT3A1, exhibits significant enrichment at distal promoters and canyon edges, but is excluded from proximal promoters and canyons where TET1 shows prominent binding. Deletion of Tet1 increases DNMT3A1 binding capacity at and around genes with wild-type TET1 binding. However, deletion of Dnmt3a has a minor effect on TET1 binding on chromatin, indicating that TET1 may limit DNA methylation partially by protecting its targets from DNMT3A and establishing boundaries for DNA methylation. Local CpG density may determine their complementary binding patterns and therefore that the methylation landscape is encoded in the DNA sequence. Furthermore, DNMT3A and TET1 impact histone modifications which in turn regulate gene expression. In particular, they regulate Polycomb Repressive Complex 2 (PRC2)-mediated H3K27me3 enrichment to constrain gene expression from bivalent promoters. Conclusions We conclude that DNMT3A and TET1 regulate the epigenome and gene expression at specific targets via their functional interplay.

BackgroundProstate cancer (PCa) is one of the prevalent malignant tumors among men. It can progress to castration-resistant prostate cancer (CRPC), which is significantly more challenging to treat. Saikosaponin A (SSA), a triterpenoid saponin extracted from the genus Bupleurum, exerts numerous pharmacological effects, including anti-inflammatory and anti-tumorigenic effects. However, the mechanism underlying the effects of SSA in prostate cancer treatment remains elusive.MethodsIn this study, a network pharmacology approach was applied to identify relevant targets from drug- and disease-related databases, and intersections were analyzed using Venny2.1 to construct a Protein-Protein interaction (PPI) interaction network. Next, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to elucidate associated biological functions and signaling pathways. Meanwhile, molecular docking between core targets and SSA was performed using Autodock software. Lastly, in vitro experiments were performed for validation.ResultsA least of four key targets, namely BCL2 apoptosis regulator (BCL2), estrogen receptor 1 (ESR1), hypoxia-inducible factor 1 subunit alpha (HIF1A), and signal transducer and activator of transcription 3 (STAT3) were identified in this study, and molecular docking analyses revealed that SSA stably binds to these targets. Moreover, the results of in vitro experiments revealed that SSA significantly inhibited the proliferative and migratory abilities of PC3 cells in a dose-dependent manner. Finally, SSA also induced G1-phase blockade and apoptosis in PC3 cells, further highlighting its potential role in prostate cancer treatment.ConclusionThe present study revealed that SSA exerts anti-tumorigenic effects in prostate cancer by targeting multiple pathways, laying a theoretical reference for its use as a therapeutic candidate for prostate cancer.

Normally the optical wafer inspection tools are used for advanced process control in high volume manufacturing of semiconductor devices. The SEM Review is done for limited sample of inspection defects to do defect based process characterization. The defect classes that are monitored normally indicate process and random defect issues. There is limited to no information of patterning related issues in real time defect monitor. Moreover, with the objective of process integration engineering of multiple processes it becomes harder to see the evolution of a defect in the line. The Die-to-Database Pattern Monitor (D2DB-PM) solution has addressed this problem. It uses the existing high resolution images from the Review and Metrology tools and compares the pattern shapes with the design reference. This way it captures patterning deviations in real time. Here we report the subtle defect problem encountered in process integration and the results from using the D2DB-PM solution. We found that this approach reduces the workload on CDSEM tools by analyzing SEM Review images instead and the automated reports improves the efficiency of all process teams.