title: Isolation of a novel rat neural progenitor clone that expresses Dlx family transcription factors and gives rise to functional GABAergic neurons in culture.
abstract: Gamma-aminobutyric acid (GABA) ergic interneurons are lost in conditions including epilepsy and central nervous system injury, but there are few culture models available to study their function. Toward the goal of obtaining renewable sources of GABAergic neurons, we used the molecular profile of a functionally incomplete GABAergic precursor clone to screen 17 new clones isolated from GFP(+) rat E14.5 cortex and ganglionic eminence (GE) that were generated by viral introduction of v-myc. The clones grow as neurospheres in medium with FGF2, and after withdrawal of FGF2, they exhibit varying patterns of differentiation. Transcriptional profiling and quantitative reverse transcriptase polymerase chain reaction (RT-PCR) indicated that one clone (GE6) expresses high levels of mRNAs encoding Dlx1, 2, 5, and 6, glutamate decarboxylases, and presynaptic proteins including neuropeptide Y and somatostatin. Protein expression confirmed that GE6 is a progenitor with restricted differentiation giving rise mostly to neurons with GABAergic markers. In cocultures with hippocampal neurons, GE6 neurons became electrically excitable and received both inhibitory and excitatory synapses. After withdrawal of FGF2 in cultures of GE6 alone, neurons matured to express βIII-tubulin, and staining for synaptophysin and vesicular GABA transporter were robust after 1-2 weeks of differentiation. GE6 neurons also became electrically excitable and displayed synaptic activity, but synaptic currents were carried by chloride and were blocked by bicuculline. The results suggest that the GE6 clone, which is ventrally derived from the GE, resembles GABAergic interneuron progenitors that migrate into the developing forebrain. This is the first report of a relatively stable fetal clone that can be differentiated into GABAergic interneurons with functional synapses.
authors.affiliation: W.M. Keck Center for Collaborative Neuroscience, Rutgers Stem Cell Research Center, Rutgers, State University of New Jersey, Piscataway, New Jersey 08854-8082, USA. hedongli2009@gmail.com
authors.forename: Hedong
authors.initials: H
authors.lastname: Li
authors.forename: Anna T
authors.initials: AT
authors.lastname: Hader
authors.forename: Yu R
authors.initials: YR
authors.lastname: Han
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Wong
authors.forename: Joanne
authors.initials: J
authors.lastname: Babiarz
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Ricupero
authors.forename: Sasha Blue
authors.initials: SB
authors.lastname: Godfrey
authors.forename: John P
authors.initials: JP
authors.lastname: Corradi
authors.forename: Myles
authors.initials: M
authors.lastname: Fennell
authors.forename: Ronald P
authors.initials: RP
authors.lastname: Hart
authors.forename: Mark R
authors.initials: MR
authors.lastname: Plummer
authors.forename: Martin
authors.initials: M
authors.lastname: Grumet
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology* / Q000378:metabolism; D059330:GABAergic Neurons / Q000166:cytology* / Q000378:metabolism; D020869:Gene Expression Profiling; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D058953:Neural Stem Cells / Q000166:cytology* / Q000378:metabolism; D055495:Neurogenesis / Q000502:physiology*; D051381:Rats; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: C088334:Distal-less homeobox proteins; D018398:Homeodomain Proteins; D014157:Transcription Factors