Roger F. Duncan

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The molecular mechanisms underlying the initiation and control of the release of cytochrome c during mitochondrion-dependent apoptosis are thought to involve the phosphorylation of mitochondrial Bcl-2 and Bcl-x(L). Although the c-Jun N-terminal kinase (JNK) has been proposed to mediate the phosphorylation of Bcl-2/Bcl-x(L) the mechanisms linking the(More)
Five major isoelectric focusing (IEF) parameters--volt-hours; concentrations of acrylamide, NaOH, and H3PO4; and equilibration time--were systematically varied to determine the effect of each on two-dimensional IEF/sodium dodecyl sulfate-polyacrylamide gel electrophoresis gel patterns and to optimize IEF conditions. Alterations in each parameter affected(More)
A clone encoding the alpha-subunit of eukaryotic initiation factor 2 (eIF-2 alpha) was isolated from a lambda gt11 expression library of rat brain cDNAs. The fusion protein expressed by the recombinant phage reacts with eIF-2 alpha antiserum except when the serum is preadsorbed with pure eIF-2. The translation of hybrid-selected HeLa cell mRNA produces two(More)
Low-density lipoprotein (LDL) oxidation mediated by a variety of catalysts in atherosclerotic lesions plays a crucial role in the genesis and evolution of atherosclerotic plaques. In this study we focused on oxidative properties of hemoglobin (Hb)-modified LDL because Hb is present in atherosclerotic lesions. Under low oxygen tensions Hb was previously(More)
Protein synthesis initiation factors in purified preparations and in crude lysates of HeLa cells were fractionated by two-dimensional polyacrylamide gel electrophoresis in order to characterize their molecular forms. Specific spots in the complex cytoplasmic protein gel pattern which corresponded to the initiation factor proteins were identified by(More)
Initiation factor eIF-4F, a multiprotein cap binding protein complex, was purified from HeLa cells by m7G affinity chromatography and independently by phosphocellulose column chromatography. The m7G affinity-purified sample contains three major proteins, p220, eIF-4A, and p28 (also known as CBP-I or eIF-4E). The abundancies of these proteins are roughly 2,(More)
There is a major disparity between the number of polysomal mRNA species found in mammalian cells and the number of polypeptides detected by high-resolution two-dimensional polyacrylamide gel electrophoresis. Here we show that technical factors are not responsible for the relative paucity of proteins, and that the translation products of rare mRNAs would be(More)
Preferential translation of Drosophila heat shock protein 70 (Hsp70) mRNA requires only the 5'-untranslated region (5'-UTR). The sequence of this region suggests that it has relatively little secondary structure, which may facilitate efficient protein synthesis initiation. To determine whether minimal 5'-UTR secondary structure is required for preferential(More)
Dysregulated cell growth can be caused by increased activity of protein synthesis eukaryotic initiation factor (eIF) 4E. Dysregulated cell growth is also characteristic of atherosclerosis. It is postulated that exposure of vascular cells, such as endothelial cells, smooth muscle cells and monocytes/macrophages, to oxidants, such as oxidized low-density(More)
Heat shock in Drosophila results in repression of most normal (non-heat shock) mRNA translation and the preferential translation of the heat shock mRNAs. The sequence elements that confer preferential translation have been localized to the 5'-untranslated region (5'-UTR) for Hsp22 and Hsp70 mRNAs (in Drosophila). Hsp90 mRNA is unique among the heat shock(More)