title: Direct evidence that ventral forebrain cells migrate to the cortex and contribute to the generation of cortical myelinating oligodendrocytes.
abstract: Cortical neuroepithelial cells generate neurons, astrocytes, and oligodendrocytes (OLs) in vitro. However, whether cortical OLs are derived from the cortical neuroepithelium or migrate from the ventral forebrain is under severe debate yet. This is due to the fact that OL progenitor cells (OPCs), as marked by the expression of PDGFRalpha or NG2, are generated at around embryonic day (E) 11 or 12 in the mouse ganglionic eminences, but the myelinating OLs appear during the second week postnatally in the cortex. There has been no labeling method for long-term glial cell-lineage tracing. Thus, we developed a new strategy: plasmid DNA encoding Cre recombinase was introduced into the Cre/loxP reporter forebrain in ventral- or dorsal-specific manner by in utero DNA electroporation. The reporter gfp gene is expressed permanently owing to the chromosomal DNA recombination. The GFP-labeled myelinating OLs were detected in the adult cortex when electroporation was targeted to the ventral neuroepithelium, demonstrating at least some of the myelinating OLs are derived from the ventral forebrain. However, when electroporation was targeted to the dorsal, we could not find GFP-labeled myelinating OLs. This suggests that the progenitors of cortical OPCs are absent or located at restricted regions in the dorsal forebrain (cortex) at E12.
authors.affiliation: Laboratory of Neurobiology and Bioinformatics, National Institute for Physiological Sciences, 5-1 Higashiyama, Myodaiji, Okazaki 444-8787, Japan.
authors.forename: Eiko
authors.initials: E
authors.lastname: Nakahira
authors.forename: Tetsushi
authors.initials: T
authors.lastname: Kagawa
authors.forename: Takeshi
authors.initials: T
authors.lastname: Shimizu
authors.forename: Martyn D
authors.initials: MD
authors.lastname: Goulding
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ikenaka
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D019070:Cell Lineage; D002465:Cell Movement; D002540:Cerebral Cortex / Q000166:cytology* / Q000196:embryology; D018274:Electroporation; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D019426:Integrases / Q000235:genetics; D051379:Mice; D009186:Myelin Sheath / Q000502:physiology*; D009474:Neurons / Q000166:cytology*; D009836:Oligodendroglia / Q000166:cytology* / Q000378:metabolism; D016548:Prosencephalon / Q000166:cytology* / Q000196:embryology
chemical_list: C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; C045073:Cre recombinase; D019426:Integrases