The marking of DNA, histones, and RNA is central to gene expression regulation in development and disease. Recent evidence links N6-methyladenosine (mA), installed on RNA by the METTL3-METTL14 methyltransferase complex, to histone modifications, but the link between mA and DNA methylation remains scarcely explored. This study shows that METTL3-METTL14 recruits the DNA methyltransferase DNMT1 to chromatin for gene-body methylation.
View Article and Find Full Text PDFPyruvate metabolism defects lead to severe neuropathies such as the Leigh syndrome (LS) but the molecular mechanisms underlying neuronal cell death remain poorly understood. Here, we unravel a connection between pyruvate metabolism and the regulation of the epitranscriptome that plays an essential role during brain development. Using genetically engineered mouse model and primary neuronal cells, we identify the transcription factor E4F1 as a key coordinator of AcetylCoenzyme A (AcCoA) production by the pyruvate dehydrogenase complex (PDC) and its utilization as an essential co-factor by the Elongator complex to acetylate tRNAs at the wobble position uridine 34 (U).
View Article and Find Full Text PDFLung metastases occur in up to 54% of patients with metastatic tumours. Contributing factors to this high frequency include the physical properties of the pulmonary system and a less oxidative environment that may favour the survival of cancer cells. Moreover, secreted factors from primary tumours alter immune cells and the extracellular matrix of the lung, creating a permissive pre-metastatic environment primed for the arriving cancer cells.
View Article and Find Full Text PDFIntestinal tuft cells are critical for anti-helminth parasite immunity because they produce IL-25, which triggers IL-13 secretion by activated group 2 innate lymphoid cells (ILC2s) to expand both goblet and tuft cells. We show that epithelial Elp3, a tRNA-modifying enzyme, promotes tuft cell differentiation and is consequently critical for IL-25 production, ILC2 activation, goblet cell expansion and control of Nippostrongylus brasiliensis helminth infection in mice. Elp3 is essential for the generation of intestinal immature tuft cells and for the IL-13-dependent induction of glycolytic enzymes such as Hexokinase 1 and Aldolase A.
View Article and Find Full Text PDFThe kinetics of the protein elongation cycle by the ribosome depends on intertwined factors. One of these factors is the electrostatic interaction of the nascent protein with the ribosome exit tunnel. In this computational biology theoretical study, we focus on the rate of the peptide bond formation and its dependence on the ribosome exit tunnel electrostatic potential profile.
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