Selective down-regulation of the pro-enkephalin gene during differentiation of a multiple neuropeptide-co-expressing cell line.
Regulation of co-expression of three neuropeptide genes, i.e. genes encoding enkephalin, cholecystokinin, and gastrin-releasing peptide, was studied in human neuroepithelioma cells. In nondifferentiated state, the continuous cell line SK-N-MC displayed an equally high level of expression of the enkephalin, cholecystokinin, and gastrin-releasing peptide genes. By culturing in medium containing endothelial cell growth supplement the SK-N-MC cells differentiated morphologically into a cell type with neurite-like processes. After 3 days the expression of the enkephalin gene in endothelial cell growth supplement-differentiated cells was significantly reduced by 75% as compared to the nondifferentiated cells, while there was no change in the expression of the cholecystokinin and gastrin-releasing peptide genes during differentiation. The results show that the enkephalin gene is selectively down-regulated during differentiation of neuroepithelioma cells. It is suggested that the down-regulation is related to the transient expression of the enkephalin gene in developing brain and other organs. Thus the neuroepithelioma cell line may provide a cellular model to study the underlying molecular mechanism.
Rudolf Magnus Institute, Medical Faculty, University of Utrecht, The Netherlands.
M A
MA
Verbeeck
M
M
Draaijer
J P
JP
Burbach
D015152:Blotting, Northern; D002454:Cell Differentiation; D002460:Cell Line; D002766:Cholecystokinin / Q000235:genetics*; D004745:Enkephalins / Q000235:genetics*; D019886:Gastrin-Releasing Peptide; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D066298:In Vitro Techniques; D018241:Neuroectodermal Tumors, Primitive, Peripheral / Q000235:genetics*; D010455:Peptides / Q000235:genetics*; D011498:Protein Precursors / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics
D004745:Enkephalins; D010455:Peptides; D011498:Protein Precursors; D012333:RNA, Messenger; D012334:RNA, Neoplasm; C029992:proenkephalin; D019886:Gastrin-Releasing Peptide; D002766:Cholecystokinin