小中大4#
【正题名】: Biochemical and molecular consequences of Ethidium bromide treatment onDrosophila cells
【作者】: Morel F Debise R Renoux M Touraille S Ragno M Alziari S
【刊名】: Insect biochemistry and molecular biology
【年卷期】: Vol.29,No.9,1999
【出版年】: 1999
【ISSN】: 0965-1748
【页码】: p.835-843
【总页数】: 9
【分类号】: Q955
【关键词】: ATP DNA genes mitochondria mitochondrial DNA mutations polymorphismrespiration molecular genetics genetics agricultural entomology Drosophila arthropods
【正文语种】: eng
【文摘】:KC167 Drosophila cells were incubated with low concentrations of Ethidiumbromide (200 ng/ml), causing changes in mitochondrial DNA (mtDNA) content (2-184% of that ofcontrols). SSCP (single strand conformational polymorphism) analysis of mtDNA indicated that theincubation with Ethidium bromide also generated mutations. Compared with controls, there were markedreductions in the activities of respiratory complexes III and IV measured in these cells, and inrespiration and ATP synthesis capacitiesmeasured in isolated mitochondria. These reductions matchedthat in mtDNA content. In contrast, no link could be demonstrated between mtDNA content andsteady-state concentrations of the transcripts of genes COIII and Cyt b.
5#
【正题名】: Ethidium bromide-induced inhibition of mitochondrial gene transcriptionsuppresses glucose-stimulated insulin release in the mouse pancreatic beta-cell line betaHC9.
【作者】: Hayakawa,T Noda,M Yasuda,K Yorifuji,H Taniguchi,S Miwa,I Sakura,H Terauchi,YHayashi,J Sharp,GW Kanazawa,Y Akanuma,Y Yazaki,Y Kadowaki,T
【作者单位】:Third Department of Internal Medicine, Faculty of Medicine, University ofTokyo, Bunkyo-ku, Tokyo 113, Japan.
【刊名】: The Journal of Biological Chemistry
【年卷期】: V.273,no.32,1998
【出版年】: 1998
【ISSN】: 0021-9258
【页码】: P.20300-20307
【总页数】: 8
【分类号】: R3
【关键词】: DNA, Mitochondrial Ethidium Glucose Insulin Islets of LangerhansTranscription, Genetic DNA, 线粒体 胡米胺 葡萄糖 胰岛素 胰岛 转录, 遗传
【正文语种】: eng
【文摘】:Recently, a mitochondrial mutation was found to be associated with maternallyinherited diabetes mellitus (Kadowaki, T., Kadowaki, H., Mori, Y., Tobe, K., Sakuta, R., Suzuki,Y., Tanabe, Y, Sakura, H., Awata, T., Goto, Y., Hayakawa, T., Matsuoka, K., Kawamori, R., Kamada,T., Horai, S., Nonaka, I., Hagura, R., Akanuma, Y., and Yazaki, Y. (1994) N. Engl. J. Med. 330,962-968). In order to elucidate its etiology, we have investigated the involvement of mitochondrialfunction in insulin secretion. Culture of the pancreatic beta-cell line, betaHC9, with low doseEthidium bromide (EBlack Eye (0.4 microg/ml) for 2-6 days resulted in a substantial decrease in thetranscription level of mitochondrial DNA (to 10-20% of the control cells) without changing its copynumber, whereas the transcription of nuclear genes was grossly unaffected. Electron microscopicanalysis revealed that treatment by EB caused morphological changes only in mitochondria and not inother organelles such as nuclei, endoplasmic reticula, Golgi bodies, or secretory granules. When thecells were treated with EB for 6 days, glucose (20 mM) could no longer stimulate insulin secretion,while glibenclamide (1 microM) still did. When EB was removed after 3- or 6-day treatment,mitochondrial gene transcription recovered within 2 days, and the profiles of insulin secretionreturned to normal within 7 days. Studies with fura-2 indicated that in EB-treated cells, glucose(20 mM) failed to increase intracellular Ca2+, while the effect of glibenclamide (1 microM) wasmaintained. Our system provides a unique way to investigate the relationship between mitochondrialfunction and insulin secretion.
