Adv Biol Regul
November 2024
The Trans Golgi Network (TGN)/endosomal system is a sorting center for cargo brought via the anterograde secretory pathway and the endocytic pathway that internalizes material from the plasma membrane. As many of the cargo that transit this central trafficking hub are components of key homeostatic signaling pathways, TGN/endosomes define a critical signaling hub for cellular growth control. A particularly interesting yet incompletely understood aspect of regulation of TGN/endosome function is control of this system by two families of lipid exchange/lipid transfer proteins.
View Article and Find Full Text PDFUnlabelled: Diffuse intrinsic pontine gliomas (DIPGs), a major type of pediatric high-grade gliomas located in the pons, are the leading cause of death in children with brain cancer. A subset (20-25%) of DIPGs harbor a lysine 27-to-methionine (K27M) mutation in , which encodes histone H3.1, and an activating mutation.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Cell Biol Lipids
October 2024
PtdIns and its phosphorylated derivatives, the phosphoinositides, are the biochemical components of a major pathway of intracellular signaling in all eukaryotic cells. These lipids are few in terms of cohort of unique positional isomers, and are quantitatively minor species of the bulk cellular lipidome. Nevertheless, phosphoinositides regulate an impressively diverse set of biological processes.
View Article and Find Full Text PDFRegulated hydrolysis of the phosphoinositide phosphatidylinositol(4,5)-bis-phosphate to diacylglycerol and inositol-1,4,5-P defines a major eukaryotic pathway for translation of extracellular cues to intracellular signaling circuits. Members of the lipid-activated protein kinase C isoenzyme family (PKCs) play central roles in this signaling circuit. One of the regulatory mechanisms employed to downregulate stimulated PKC activity is via a proteasome-dependent degradation pathway that is potentiated by peptidyl-prolyl isomerase Pin1.
View Article and Find Full Text PDFPhospholipase D (PLD) hydrolyses phosphatidylcholine (PtdCho) to produce free choline and the critically important lipid signaling molecule phosphatidic acid (PtdOH). Since the initial discovery of PLD activities in plants and bacteria, PLDs have been identified in a diverse range of organisms spanning the taxa. While widespread interest in these proteins grew following the discovery of mammalian isoforms, research into the PLDs of non-mammalian organisms has revealed a fascinating array of functions ranging from roles in microbial pathogenesis, to the stress responses of plants and the developmental patterning of flies.
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