title: A p38 inhibitor allows to dissociate differentiation and apoptotic processes triggered upon LIF withdrawal in mouse embryonic stem cells.
abstract: Mouse embryonic stem cells remain pluripotent when maintained in the presence of leukemia inhibitory factor (LIF). Upon LIF withdrawal, most cells differentiate into various lineages, while some die by apoptosis within 3 days. We have analyzed the activation pattern of the mitogen-activated protein kinase (MAPK) families and characterized the expression profile of selected genes modulated during differentiation or apoptosis. We show that p38 MAPKs are activated first, during the apoptotic crisis, while extracellular-regulated kinases and c-Jun N-terminal kinases are induced after the apoptotic crisis in differentiated cells. However, by using both p38 kinase inhibitors (PD169316 and SB203580) and a p38alpha(-/-) cell line, we demonstrate that p38alpha activation is rather a consequence than a cause of apoptosis. We thus reveal novel properties of PD169316, which induces cell survival without impairing cell differentiation, and identify PD169316-sensitive targets like the fibroblast growth factor-5, Brachyury and bcl-2 genes. Finally, we demonstrate that overexpression of the PD169316 - regulated bcl-2 gene prevents LIF withdrawal - induced cell death.
authors.affiliation: Institut de Génétique et de Biologie Moleculaire et Cellulaire, CNRS/INSERM/ULP, B.P. 10142, 67404 Illkirch Cedex, C.U. de Strasbourg, France.
authors.forename: D
authors.initials: D
authors.lastname: Duval
authors.forename: M
authors.initials: M
authors.lastname: Malaisé
authors.forename: B
authors.initials: B
authors.lastname: Reinhardt
authors.forename: C
authors.initials: C
authors.lastname: Kedinger
authors.forename: H
authors.initials: H
authors.lastname: Boeuf
mesh_terms: D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D020169:Caspases / Q000187:drug effects / Q000378:metabolism; D002454:Cell Differentiation; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002999:Clone Cells; D003470:Culture Media; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005434:Flow Cytometry; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D049452:Green Fluorescent Proteins; D007093:Imidazoles / Q000494:pharmacology; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; D008164:Luminescent Proteins / Q000378:metabolism; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism
chemical_list: D003470:Culture Media; D004791:Enzyme Inhibitors; D007093:Imidazoles; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse; D008164:Luminescent Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011725:Pyridines; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D020928:Mitogen-Activated Protein Kinases; D020169:Caspases; C408604:2-(4-nitrophenyl)-4-(4-fluorophenyl)-5-(4-pyridinyl)-1H-imidazole; C093642:SB 203580