title: Geminin regulates the transcriptional and epigenetic status of neuronal fate-promoting genes during mammalian neurogenesis.
abstract: Regulating the transition from lineage-restricted progenitors to terminally differentiated cells is a central aspect of nervous system development. Here, we investigated the role of the nucleoprotein geminin in regulating neurogenesis at a mechanistic level during both Xenopus primary neurogenesis and mammalian neuronal differentiation in vitro. The latter work utilized neural cells derived from embryonic stem and embryonal carcinoma cells in vitro and neural stem cells from mouse forebrain. In all of these contexts, geminin antagonized the ability of neural basic helix-loop-helix (bHLH) transcription factors to activate transcriptional programs promoting neurogenesis. Furthermore, geminin promoted a bivalent chromatin state, characterized by the presence of both activating and repressive histone modifications, at genes encoding transcription factors that promote neurogenesis. This epigenetic state restrains the expression of genes that regulate commitment of undifferentiated stem and neuronal precursor cells to neuronal lineages. However, maintaining geminin at high levels was not sufficient to prevent terminal neuronal differentiation. Therefore, these data support a model whereby geminin promotes the neuronal precursor cell state by modulating both the epigenetic status and expression of genes encoding neurogenesis-promoting factors. Additional developmental signals acting in these cells can then control their transition toward terminal neuronal or glial differentiation during mammalian neurogenesis.
authors.affiliation: Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, USA.
authors.forename: Dhananjay
authors.initials: D
authors.lastname: Yellajoshyula
authors.forename: Jong-won
authors.initials: JW
authors.lastname: Lim
authors.forename: Dominic M
authors.initials: DM
authors.lastname: Thompson
authors.forename: Jacob S
authors.initials: JS
authors.lastname: Witt
authors.forename: Ethan S
authors.initials: ES
authors.lastname: Patterson
authors.forename: Kristen L
authors.initials: KL
authors.lastname: Kroll
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D002454:Cell Differentiation; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D004625:Embryo, Nonmammalian; D053595:Embryonic Stem Cells / Q000166:cytology / Q000378:metabolism; D044127:Epigenesis, Genetic; D064248:Geminin; D018507:Gene Expression Regulation, Developmental; D006657:Histones / Q000235:genetics / Q000378:metabolism; D051379:Mice; D014411:Neoplastic Stem Cells / Q000166:cytology / Q000378:metabolism; D058953:Neural Stem Cells / Q000166:cytology / Q000378:metabolism; D055495:Neurogenesis / Q000235:genetics*; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics* / Q000378:metabolism; D016548:Prosencephalon / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D015533:Transcriptional Activation; D029867:Xenopus Proteins; D014982:Xenopus laevis / Q000196:embryology / Q000235:genetics* / Q000378:metabolism
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D018797:Cell Cycle Proteins; D002843:Chromatin; D064248:Geminin; D006657:Histones; D009687:Nuclear Proteins; D029867:Xenopus Proteins; C577998:GMNN protein, Xenopus; C577997:Gmnn protein, mouse