RNA methylation at adenosine N6 (m6A) is one of the most common RNA modifications, impacting RNA stability, transport, and translation. Previous studies uncovered RNA destabilization in amyotrophic lateral sclerosis (ALS) models in association with accumulation of the RNA-binding protein TDP43. Here, we show that TDP43 recognizes m6A RNA and that RNA methylation is critical for both TDP43 binding and autoregulation.
View Article and Find Full Text PDFDespite their high degree of identity and even higher homology, the two Kat3 transcriptional coactivators, CBP and p300, have distinct functions, particularly within the Wnt/β-catenin signaling cascade. ICG-001, by directly binding to CBP but not p300, inhibits CBP/β-catenin transcription and has served as an invaluable chemical genomic tool to dissect the Wnt signaling cascade and the divergent roles of these two coactivators. However, to date no direct antagonist of the p300/β-catenin interaction has been reported.
View Article and Find Full Text PDFAn optimal culture system for human pluripotent stem cells should be fully defined and free of animal components. To date, most xeno-free culture systems require human feeder cells and/or highly complicated culture media that contain activators of the fibroblast growth factor (FGF) and transforming growth factor-β (TGFβ) signaling pathways, and none provide for replacement of FGF/TGFβ ligands with chemical compounds. The Wnt/β-catenin signaling pathway plays an important role in mouse embryonic stem cells in leukemia inhibitory factor-independent culture; however, the role of Wnt/β-catenin signaling in human pluripotent stem cell is still poorly understood and controversial because of the dual role of Wnts in proliferation and differentiation.
View Article and Find Full Text PDFAm J Respir Cell Mol Biol
December 2012
In this study, we explored the regulation and the role of up-regulated microRNAs in idiopathic pulmonary fibrosis (IPF), a progressive interstitial lung disease of unknown origin. We analyzed the expression of microRNAs in IPF lungs and identified 43 significantly up-regulated microRNAs. Twenty-four of the 43 increased microRNAs were localized to the chromosome 14q32 microRNA cluster.
View Article and Find Full Text PDFBecause of their central role in programmed cell death, the caspases are attractive targets for developing new therapeutics against cancer and autoimmunity, myocardial infarction and ischemic damage, and neurodegenerative diseases. We chose to target caspase-3, an executioner caspase, and caspase-8, an initiator caspase, based on the vast amount of information linking their functions to diseases. Through a structure-based drug design approach, a number of novel beta-strand peptidomimetic compounds were synthesized.
View Article and Find Full Text PDFEmbryonic stem cells (ESCs) represent an important research tool and a potential resource for regenerative medicine. Generally, ESCs are cocultured with a supportive feeder cell layer of murine embryonic fibroblasts, which maintain the ESCs' capacity for self-renewal and block spontaneous differentiation. These cumbersome conditions, as well as the risk of xenobiotic contamination of human ESCs grown on murine embryonic fibroblasts, make it a priority to develop chemically defined methods that can be safely used for the expansion of ESCs.
View Article and Find Full Text PDFChemical genomics is a powerful method to complement more traditional genetic techniques (i.e. knockout mice, siRNA) for the dissection of complex signaling networks.
View Article and Find Full Text PDF1 The nuclear translocation of transcription factors may be a critical factor in the intracellular pathway involved in ischaemia/reperfusion (I/R) injury. Here, we examined whether NF-kappaB and AP-1 participated in the cascade of events leading to TNF-alpha production, neutrophil recruitment, tissue injury and lethality following intestinal I/R. 2 The superior mesenteric artery (SMA) of mice was made ischaemic for 60 min followed by 30 min of reperfusion.
View Article and Find Full Text PDFComb Chem High Throughput Screen
November 2003
There is increasing evidence that redox regulation of transcription, particularly activator protein-1 (AP-1) and nuclear factor kappa B (NF-kappaB), is important in inflammatory diseases. Human thioredoxin (TRX), a member of the oxidoreductase superfamily, was initially identified, as a factor which augments the production of interleukin-2 receptor alpha (IL-2R alpha) in human T-cell lymphotropic virus type 1 (HTLV-1) infected patient T-cells. Substrates for the redox activity of TRX bind the active site cleft in extended strand structure.
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