Visualization of S100B-positive neurons and glia in the central nervous system of EGFP transgenic mice.
S100B, the EF-hand Ca(++)-binding protein with gliotrophic and neurotrophic properties implicated in the pathogenesis of Alzheimer's disease, is coined as a glial marker, despite its documented presence in rodent brain neurons. We have generated a transgenic mouse whose EGFP reporter, controlled by the -1,669/+3,106 sequence of the murine S100B gene, allows the direct microscopic observation of most S100B-expressing cells in the central nervous system (CNS). From embryonic day 13 onward, EGFP expression was targeted to selected neuroepithelial, glial, and neuronal cells, indicating that cell-specific expression of S100B is regulated at the transcriptional level during development. In adult mice, the highest level of EGFP expression was found in ependymocytes; astrocytes; and spinal, medullar, pontine, and deep cerebellar S100B neurons. Our results, thus, agree with earlier reports suggesting that S100B is not a CNS glial-specific marker. In addition, we detected EGFP and S100B in forebrain neurons previously thought not to express S100B in the mouse, including neurons of primary motor and somatosensory neocortical areas, the ventral pallidum and prerubral field. Another interesting finding was the selected EGFP targeting to neonatal S100B oligodendrocytes and adult NG2 progenitors as opposed to mature S100B oligodendrocytes. This finding suggests that, except for oligodendrocytes at the last stage of myelin maturation, the -1,669/+3,106 sequence of the S100B gene is a useful reagent for driving expression of transgenes in most S100B-expressing cells of mouse brain.
Vives
Virginie
V
Institut National de la Santé et de la Recherche Médicale U469, Centre CNRS-INSERM de Pharmacologie et d'Endocrinologie, F-34094 Montpellier Cedex 05, France.
Alonso
Gérard
G
Solal
Anne Cohen
AC
Joubert
Dominique
D
Legraverend
Catherine
C
D000818:Animals; D015153:Blotting, Western; D002490:Central Nervous System / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D009414:Nerve Growth Factors / Q000378:metabolism*; D009457:Neuroglia / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000378:metabolism*
D008164:Luminescent Proteins; D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579159:S100b protein, mouse; D049452:Green Fluorescent Proteins