Generation of oligodendrocyte precursor cells from mouse dorsal spinal cord independent of Nkx6 regulation and Shh signaling.
In the developing spinal cord, early progenitor cells of the oligodendrocyte lineage are induced in the motor neuron progenitor (pMN) domain of the ventral neuroepithelium by the ventral midline signal Sonic hedgehog (Shh). The ventral generation of oligodendrocytes requires Nkx6-regulated expression of the bHLH gene Olig2 in this domain. In the absence of Nkx6 genes or Shh signaling, the initial expression of Olig2 in the pMN domain is completely abolished. In this study, we provide the in vivo evidence for a late phase of Olig gene expression independent of Nkx6 and Shh gene activities and reveal a brief second wave of oligodendrogenesis in the dorsal spinal cord. In addition, we provide genetic evidence that oligodendrogenesis can occur in the absence of hedgehog receptor Smoothened, which is essential for all hedgehog signaling.
Cai
Jun
J
Department of Anatomical Sciences and Neurobiology, School of Medicine, University of Louisville, Louisville, KY 40292, USA.
Qi
Yingchuan
Y
Hu
Xuemei
X
Tan
Min
M
Liu
Zijing
Z
Zhang
Jianshe
J
Li
Qun
Q
Sander
Maike
M
Qiu
Mengsheng
M
D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins; D002454:Cell Differentiation / Q000502:physiology; D004268:DNA-Binding Proteins / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D007150:Immunohistochemistry; D051379:Mice; D018345:Mice, Knockout; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D000076104:Oligodendrocyte Transcription Factor 2; D009836:Oligodendroglia / Q000166:cytology / Q000378:metabolism*; D051763:PAX7 Transcription Factor; D043562:Receptors, G-Protein-Coupled / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics; D000072086:Smoothened Receptor; D013116:Spinal Cord / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics*; D014157:Transcription Factors / Q000378:metabolism
D051792:Basic Helix-Loop-Helix Proteins; D004268:DNA-Binding Proteins; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins; D000076104:Oligodendrocyte Transcription Factor 2; D051763:PAX7 Transcription Factor; D043562:Receptors, G-Protein-Coupled; D000072086:Smoothened Receptor; D015534:Trans-Activators; D014157:Transcription Factors; C499317:Ascl1 protein, mouse; C491328:Nkx6-1 protein, mouse; C512773:Olig2 protein, mouse; C497322:Pax7 protein, mouse; C509239:SHH protein, human; C491022:Smo protein, mouse