Expression of glyceraldehyde-3-phosphate dehydrogenase during differentiation of HD3 cells.
The chicken erythroblast cell line HD3, which is infected with a temperature-sensitive avian erythroleukemia virus, becomes committed to differentiate to an erythrocyte upon temperature shift in the presence of inducers (hemin and butyric acid). The activity of glyceraldehyde-3-phosphate dehydrogenase (GAD), a key enzyme in the glycolytic pathway, was examined. Upon induction of differentiation the following changes in glyceraldehyde-3-phosphate dehydrogenase activity and the corresponding mRNA level occurred. Twenty-four hours post-induction the glyceraldehyde-3-phosphate dehydrogenase message decreased and virtually disappeared within 48 h. Glyceraldehyde-3-phosphate dehydrogenase activity did not follow the mRNA level and increased within 48 h post-induction and then started to fall. The discrepancy between glyceraldehyde-3-phosphate dehydrogenase activity and the mRNA level is likely due to a difference in GAD protein and mRNA half-lives. The results also suggest that enzyme activity could be regulated by post-translational events. Chicken erythrocytes expressed reduced levels of glyceraldehyde-3-phosphate dehydrogenase activity. Thus the low level of GAD found in chicken erythrocytes is associated with a turn off of GAD gene expression upon induction of erythroid differentiation.
Division of Molecular Medicine, Rudjer Bosković Institute, Zagreb/Croatia.
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D000249:Adenosine Monophosphate / Q000378:metabolism; D000818:Animals; D002087:Butyrates / Q000494:pharmacology; D020148:Butyric Acid; D002454:Cell Differentiation; D002478:Cells, Cultured; D002645:Chickens; D003513:Cycloheximide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D004900:Erythroblasts / Q000187:drug effects / Q000201:enzymology*; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D006531:HEPES / Q000494:pharmacology; D006207:Half-Life; D006427:Hemin / Q000494:pharmacology; D006358:Hot Temperature; D019271:Hypoxanthine / Q000378:metabolism; D007288:Inosine / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D013997:Time Factors
D002087:Butyrates; D012333:RNA, Messenger; D020148:Butyric Acid; D003609:Dactinomycin; D019271:Hypoxanthine; D000249:Adenosine Monophosphate; D007288:Inosine; D006427:Hemin; D003513:Cycloheximide; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D006531:HEPES