Glial differentiation does not require a neural ground state.
Glial cells differentiate from the neuroepithelium. In flies, gliogenesis depends on the expression of glial cell deficient/glial cell missing (glide/gcm). The phenotype of glide/gcm loss- and gain-of-function mutations suggested that gliogenesis occurs in cells that, by default, would differentiate into neurons. Here we show that glide/gcm is able to induce cells even from a distinct germ layer, the mesoderm, to activate the glial developmental program, which demonstrates that gliogenesis does not require a ground neural state. These findings challenge the common view on the establishment of cell diversity in the nervous system. Strikingly, ectopic glide/gcm overrides positional information by repressing the endogenous developmental program. These findings also indicate that glial differentiation tightly depends on glide/gcm transcriptional regulation. It is likely that glide/gcm homologs act similarly during vertebrate gliogenesis.
Institut de Génétique et Biologie Moléculaire et Cellulaire, IGBMC/CNRS/ULP-BP 163 67404 Illkirch, c.u. de Strasbourg, France.
R
R
Bernardoni
A A
AA
Miller
A
A
Giangrande
D000818:Animals; D030801:Animals, Genetically Modified; D002454:Cell Differentiation / Q000235:genetics*; D004268:DNA-Binding Proteins; D004330:Drosophila / Q000196:embryology*; D029721:Drosophila Proteins; D004475:Ectoderm / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008648:Mesoderm / Q000378:metabolism; D024510:Muscle Development; D009457:Neuroglia / Q000502:physiology*; D009474:Neurons / Q000378:metabolism; D009479:Neuropeptides / Q000502:physiology*; D015534:Trans-Activators / Q000502:physiology*; D014157:Transcription Factors
D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C102805:GCM protein, Drosophila; D009479:Neuropeptides; D015534:Trans-Activators; D014157:Transcription Factors