Sialic acid metabolism is involved in the regulation of gene expression during neuronal differentiation of PC12 cells.
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.
Kontou
Maria
M
Institut für Biochemie und Molekularbiologie, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Arnimallee 22, 14195, Berlin-Dahlem, Germany. maria.kontou@charite.de
Bauer
Christian
C
Reutter
Werner
W
Horstkorte
Rüdiger
R
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics; D000818:Animals; D002454:Cell Differentiation; D005786:Gene Expression Regulation; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D019158:N-Acetylneuraminic Acid / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000235:genetics; D009474:Neurons / Q000166:cytology* / Q000378:metabolism*; D016716:PC12 Cells; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D051381:Rats
D048868:Adaptor Proteins, Signal Transducing; C413755:Dpysl5 protein, rat; D009419:Nerve Tissue Proteins; D016755:Proto-Oncogene Proteins c-jun; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D019158:N-Acetylneuraminic Acid