Glucocorticosteroids stimulate the activity of the promoters of peripheral myelin protein-22 and protein zero genes in Schwann cells.
To better understand the mechanism by which glucocorticosteroids (GLUC) could enhance myelination in the PNS, cultured rat Schwann cells were transiently transfected with reporter constructs in which luciferase expression was controlled by the promoter region of either the peripheral myelin protein-22 (PMP22) or the protein zero (P(0)) genes. GLUC stimulated the activity of the P(0) promoter and the PMP22 promoters 1 and 2. The effect of GLUC was specific as estradiol and testosterone did not activate the promoters. The antagonist RU486 did not abolish the effect of GLUC, but instead stimulated promoter activities by itself. In the mammary carcinoma cell line 34i, which expresses GLUC receptors, GLUC did not stimulate the P(0) and PMP22 promoters while the promoter of the mouse mammary tumor virus was strongly activated. Thus, the activation by GLUC of the promoter activities of two peripheral myelin protein genes is Schwann cell-specific.
Désarnaud
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F
INSERM U488, 80, rue du Général Leclerc, 94276, Le Kremlin-Bicêtre, France. fdesarna@uci.edu
Bidichandani
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S
Patel
P I
PI
Baulieu
E E
EE
Schumacher
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M
D000367:Age Factors; D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005938:Glucocorticoids / Q000378:metabolism / Q000494:pharmacology*; D018993:Myelin P0 Protein / Q000235:genetics*; D009185:Myelin Proteins / Q000235:genetics*; D009186:Myelin Sheath / Q000187:drug effects / Q000378:metabolism; D017933:Peripheral Nervous System / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D011965:Receptors, Glucocorticoid / Q000187:drug effects / Q000378:metabolism; D012583:Schwann Cells / Q000187:drug effects* / Q000378:metabolism*; D012680:Sensitivity and Specificity
D005938:Glucocorticoids; D018993:Myelin P0 Protein; D009185:Myelin Proteins; C489545:Pmp22 protein, mouse; C489546:Pmp22 protein, rat; D011965:Receptors, Glucocorticoid