Regulation of the translation and processing of rat dopamine beta-hydroxylase by metal ions in a cell free system.
Metal ions play an important role in the metabolism of prokaryotic and eukaryotic cells. In this study we examine the effect of various metal ions on the translation, glycosylation and co-translational processing of dopamine beta-hydroxylase (DBH) in vitro. The translation of wild type DBH mRNA and constructs with site directed mutations near the putative signal cleavage site was carried out with the addition of different ions (Mg2+, Cu2+, Mn2+, Ni2+, Co2+, Zn2+, Pb2+, Fe2+, Fe3+, Ca2+) in a cell-free system in the present of microsomal membranes. Most of the metal ions inhibited translation at concentrations above 1.5 mM. The translation was more sensitive to Fe2+ than Fe3+. Ni2+ and Cu2+ preferentially inhibited formation of the glycosylated products. Only magnesium affected the ratio of the two different processed forms in a concentration dependent manner.
Feng
Z
Z
Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla 10595, USA.
Sabban
E L
EL
D000818:Animals; D002474:Cell-Free System; D004299:Dopamine beta-Hydroxylase / Q000235:genetics* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D006031:Glycosylation; D008670:Metals / Q000494:pharmacology*; D016297:Mutagenesis, Site-Directed / Q000235:genetics; D014176:Protein Biosynthesis / Q000187:drug effects*; D011499:Protein Processing, Post-Translational / Q000187:drug effects*; D051381:Rats
D008670:Metals; D004299:Dopamine beta-Hydroxylase