The role of iron supply in the regulation of 5-aminolevulinate synthase mRNA levels in murine erythroleukemia cells.
Mouse erythroleukemia (MEL) cells transformed by Friend virus and induced to undergo erythroid differentiation by treatment with hexamethylenebisacetamide (HMBA) increase erythroid specific 5-aminolevulinate synthase (ALAS-E) mRNA levels by 4-15-fold and decrease "housekeeping" 5-aminolevulinate synthase (ALAS-N) mRNA levels by 1.2-1.4-fold. Iron affects translation of (ALAS-E) mRNA but nothing is known about its effect at the pretranslational level of the expression of (ALAS-E) mRNA. The aim of this study was to examine the effect of iron on the synthesis of (ALAS-E) mRNA and (ALAS-N) mRNA. This effect was compared with the effect of iron on the iron on the synthesis of H-ferritin and transferrin receptor mRNAs. Incubation of uninduced or induced MEL cells with iron chelator pyridoxal isonicotinoyl hydrazone (PIH) or desferrioxamine (Desferal) and 3H-uridine decreased the level of the 3H-labeled (ALAS-E) mRNA. The treatment with either diferric transferrin or Fe-PIH increased the level of the 3H-labeled (ALAS-E) mRNA. The opposite effect was observed on the level of the 3H-labeled (ALAS-N) mRNA. These findings indicate that iron might play its role also at the pretranslational level of the expression of ALAS-E or in the stability of (ALAS-E) mRNA.
Fuchs
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O
Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
Ponka
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D000624:5-Aminolevulinate Synthetase / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D004273:DNA, Neoplasm / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D005293:Ferritins / Q000096:biosynthesis / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D007501:Iron / Q000378:metabolism / Q000494:pharmacology*; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D004915:Leukemia, Erythroblastic, Acute / Q000201:enzymology / Q000378:metabolism*; D051379:Mice; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger / Q000378:metabolism*; D011990:Receptors, Transferrin / Q000096:biosynthesis / Q000235:genetics; D014407:Tumor Cells, Cultured
D004273:DNA, Neoplasm; D007527:Isoenzymes; D012333:RNA, Messenger; D011990:Receptors, Transferrin; D005293:Ferritins; D007501:Iron; D000624:5-Aminolevulinate Synthetase