title: Proteomic analysis of neural differentiation of mouse embryonic stem cells.
abstract: Mouse embryonic stem cells (mESCs) can differentiate into different types of cells, and serve as a good model system to study human embryonic stem cells (hESCs). We showed that mESCs differentiated into two types of neurons with different time courses. To determine the global protein expression changes after neural differentiation, we employed a proteomic strategy to analyze the differences between the proteomes of ES cells (E14) and neurons. Using 2-DE plus LC/MS/MS, we have generated proteome reference maps of E14 cells and derived dopaminergic neurons. Around 23 proteins with an increase or decrease in expression or phosphorylation after differentiation have been identified. We confirmed the downregulation of translationally controlled tumor protein (TCTP) and upregulation of alpha-tubulin by Western blotting. We also showed that TCTP was further downregulated in derived motor neurons than in dopaminergic neurons, and its expression level was independent of extracellular Ca(2+) concentration during neural differentiation. Potential roles of TCTP in modulating neural differentiation through binding to Ca(2+), tubulin and Na,K-ATPase, as well as the functional significance of regulation of other proteins such as actin-related protein 3 (Arp3) and Ran GTPase are discussed. This study demonstrates that proteomic tools are valuable in studying stem cell differentiation and elucidating the underlying molecular mechanisms.
authors.affiliation: Life Sciences Division, Lawrence Berkeley National Laboratory, CA 94720, USA. djwang@lbl.gov
authors.forename: Daojing
authors.initials: D
authors.lastname: Wang
authors.forename: Ling
authors.initials: L
authors.lastname: Gao
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D004622:Embryo, Mammalian; D004798:Enzymes / Q000032:analysis / Q000235:genetics; D015151:Immunoblotting; D051379:Mice; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000235:genetics; D009474:Neurons / Q000737:chemistry / Q000166:cytology* / Q000201:enzymology; D010750:Phosphoproteins / Q000032:analysis / Q000235:genetics; D010766:Phosphorylation; D020543:Proteome / Q000032:analysis*; D040901:Proteomics / Q000379:methods; D013234:Stem Cells / Q000166:cytology*; D000090324:Tumor Protein, Translationally-Controlled 1; D020931:ran GTP-Binding Protein / Q000032:analysis / Q000235:genetics
chemical_list: D004798:Enzymes; D009419:Nerve Tissue Proteins; D010750:Phosphoproteins; D020543:Proteome; C000715647:TPT1 protein, human; C000715648:Tpt1 protein, mouse; D000090324:Tumor Protein, Translationally-Controlled 1; D020931:ran GTP-Binding Protein