Increased intracellular calcium alters myelin gene expression in the N20.1 oligodendroglial cell line

✍ Scribed by Diane M. Studzinski; Rose E. Callahan; Joyce A. Benjamins

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 270 KB
• Volume: 57
• Category: Article
• ISSN: 0360-4012
• DOI: 10.1002/(sici)1097-4547(19990901)57:5<633::aid-jnr5>3.0.co;2-i

✦ Synopsis

Regulation of intracellular

Ca 2؉ (Ca i ) plays a central role in cell survival, proliferation, and differentiation. We previously reported that immature oligodendroglia (OLs) are less susceptible than mature OLs to cell death following increases in Ca i (Benjamins and Nedelkoska [1995] Neurochem. Res. 21:471-479). The N20.1 murine OL cell line provides a model of an intermediate stage of OL maturation in which to study responses to Ca i increases with regard to viability, as well as the expression of mRNAs for myelin basic protein (MBP), proteolipid protein (PLP), DM-20, SCIP, and the immediate early genes ZIF268, c-fos, and c-jun. Cells were treated with the calcium ionophore A23187 or thapsigargin for 1, 3, and 18 hr. A23187 at 1.0 M had no significant effect on cell detachment or death, whereas thapsigargin at 1.0 M slightly increased both. With both agents, SCIP, MBP, and PLP mRNA levels were unaffected by 3 hr, but markedly reduced after 18 hours. DM-20 mRNA levels remained unchanged at both time points. With both agents, ZIF268, c-fos, and c-jun mRNA levels were unaffected after 1 hr; c-jun mRNA levels showed a significant increase after 3 hr of thapsigargin treatment. Thus, in N20.1 cells, increased calcium affects the IEG c-jun first, SCIP is coordinately decreased with MBP and PLP mRNAs at a later time point, and DM-20 message is under different regulation than PLP.