title: Differentiation of embryonic stem cells conditionally expressing neurogenin 3.
abstract: Expression of the proendocrine gene neurogenin 3 (Ngn3) is required for the development of pancreatic islets. To better characterize the molecular events regulated by Ngn3 during development, we have determined the expression profiles of murine embryonic stem cells (mESCs) uniformly induced to overexpress Ngn3. An mESC line was created in order to induce Ngn3 by adding doxycycline to the culture medium. Genome-wide microarray analysis was performed to identify genes regulated by Ngn3 in a variety of contexts, including undifferentiated ESCs and differentiating embryoid bodies (EBs). Genes regulated by Ngn3 in a context-independent manner were identified and analyzed using systematic gene ontology tools. This analysis revealed Notch signaling as the most significantly regulated signaling pathway (p = .009). This result is consistent with the hypothesis that Ngn3 expression makes the cell competent for Notch signaling to be activated and, conversely, more sensitive to Notch signaling inhibition. Indeed, EBs induced to express Ngn3 were significantly more sensitive to gamma-secretase inhibitor-mediated Notch signaling inhibition (p < .0001) when compared with uninduced EBs. Moreover, we find that Ngn3 induction in differentiating ESCs results in significant increases in insulin, glucagon, and somatostatin expression.
authors.affiliation: University of Wisconsin-Madison School of Medicine and Public Health, Department of Surgery, Madison, Wisconsin, USA.
authors.forename: Nathan R
authors.initials: NR
authors.lastname: Treff
authors.forename: Robert K
authors.initials: RK
authors.lastname: Vincent
authors.forename: Melisa L
authors.initials: ML
authors.lastname: Budde
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Browning
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Magliocca
authors.forename: Vivek
authors.initials: V
authors.lastname: Kapur
authors.forename: Jon S
authors.initials: JS
authors.lastname: Odorico
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D002460:Cell Line; D016000:Cluster Analysis; D053595:Embryonic Stem Cells / Q000378:metabolism*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D005934:Glucagon / Q000378:metabolism; D007328:Insulin / Q000378:metabolism; D051379:Mice; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D010179:Pancreas / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051880:Receptors, Notch / Q000378:metabolism; D012097:Repressor Proteins / Q000378:metabolism; D015398:Signal Transduction; D013004:Somatostatin / Q000378:metabolism
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D005934:Glucagon; D007328:Insulin; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D051880:Receptors, Notch; D012097:Repressor Proteins; D013004:Somatostatin; C407737:Neurog3 protein, mouse; C101750:Sim1 protein, mouse