title: A bimodal influence of thyroid hormone on cerebellum oligodendrocyte differentiation.
abstract: Thyroid hormone (T(3)) can trigger a massive differentiation of cultured oligodendrocytes precursor cells (OPC) by binding the nuclear T(3) receptor α1 (TRα1). Whether this reflects a physiological function of TRα1 remains uncertain. Using a recently generated mouse model, in which CRE/loxP recombination is used to block its function, we show that TRα1 acts at two levels for the in vivo differentiation of OPC in mouse cerebellum. At the early postnatal stage, it promotes the secretion of several neurotrophic factors by acting in Purkinje neurons and astrocytes, defining an environment suitable for OPC differentiation. At later stages, TRα1 acts in a cell-autonomous manner to ensure the complete arrest of OPC proliferation. These data explain contradictory observations made on various models and outline the importance of T(3) signaling both for synchronizing postnatal neurodevelopment and restraining OPC proliferation in adult brain.
authors.affiliation: Université Lyon 1, Centre National de la Recherche Scientifique, Institut de la Recherché Agronomique, Ecole Normale Supérieure de Lyon, 69364 Lyon Cedex 07, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Picou
authors.forename: Teddy
authors.initials: T
authors.lastname: Fauquier
authors.forename: Fabrice
authors.initials: F
authors.lastname: Chatonnet
authors.forename: Frédéric
authors.initials: F
authors.lastname: Flamant
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D002452:Cell Count; D002454:Cell Differentiation; D049109:Cell Proliferation; D002531:Cerebellum / Q000166:cytology* / Q000254:growth & development / Q000378:metabolism; D015870:Gene Expression; D020869:Gene Expression Profiling; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D009836:Oligodendroglia / Q000502:physiology*; D015398:Signal Transduction; D037021:Thyroid Hormone Receptors alpha / Q000235:genetics / Q000378:metabolism*; D013963:Thyroid Hormones / Q000502:physiology*; D014284:Triiodothyronine / Q000502:physiology*
chemical_list: D037021:Thyroid Hormone Receptors alpha; D013963:Thyroid Hormones; D014284:Triiodothyronine