Sialic acid metabolism is involved in the regulation of gene expression during neuronal differentiation of PC12 cells
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Sialic acid precursors are mediators of the sialic acid pathway. In this manuscript we present evidence that the application of sialic acid a precursor modulates gene expression and cell differentiation. The concept that sugars are involved in cellular transcription was first proposed by Jacob and Monod nearly 40 years ago studying the regulation of the lac-operon in prokaryotes. Surprisingly, these findings have never been transferred to eukaryotic systems. For our studies we have chosen PC12 cells. PC12-cells differentiate after application of NGF into a neuron-like phenotype. It is shown that treatment of PC12 cells with two different sialic acid precursors N-acetyl- or N-propanoylmannosamine, without application of NGF also induces neurite outgrowth. Moreover, the PC12 cells show the same morphology as the NGF-treated cells. Surprisingly, after application of both sialic acid precursors the phosphorylation and translocation of erk1/2 into the nucleus are activated, thus influencing the expression of genes involved in the differentiation of cells, such as the transcription factor c-Jun or TOAD-64/Ulip/CRMP (Turned ON After Division, 64 kd/ unc-33-like phosphoprotein/Collapsin Response Mediator Protein). These are the first experimental data showing that the sialic acid metabolism is closely associated with signal transduction and regulation of neuronal differentiation.
KeywordsProliferation Gene expression Differentiation
The authors are grateful to Sabine Nöhring for technical support. This work received financial support by the Deutsche Forschungsgemeinschaft, and the Fonds der Chemischen Industrie. Dr. M. Kontou received a grant of the Berliner Programm zur Förderung der Chancengleichheit für Frauen in Forschung und Lehre.
- 11.Collins, B.E., Fralich, T.J., Itonori, S., Ichikawa, V., Schnaar, R.L.: Conversion of cellular sialic acid expression from N-acetyl- to N-glycolylneuraminic acid using a synthetic precursor, N-glycolylmannosamine pentaacetate: inhibition of myelin-associated glycoprotein binding to neural cells. Glycobiology 10, 11–20 (2000)CrossRefPubMedGoogle Scholar
- 24.Quach, T.T., Mosinger Jr., B., Ricard, D., Copeland, N.G., Gilbert, D.J., Jenkins, N.A., Stankoff, B., Honnorat, J., Belin, M.F., Kolattukudy, P.: Collapsin response mediator protein-3/unc-33-like protein-4 gene: organization, chromosomal mapping and expression in the developing mouse brain. Gene 242, 175–182 (2000)CrossRefPubMedGoogle Scholar