The effects of spectinomycin and ethidium bromide on the synthesis of organelle rRNA and on ultrastructure in Ochromonas danica.
نویسندگان
چکیده
The effects of 24-h exposure to spectinomycin (100 microgram/ml) and ethidium bromide (1 microgram/ml) on the accumulation of chloroplast and mitochondrial rRNAs and on organelle ultrastructure were studied in greening cells of Ochromonas danica. Cells treated with ethidium bromide for 24 h divide at the same rate as controls but contain less than one third the normal amount of mitochondrial rRNA. Ultrastructural observations showed that these cells contain only 10% the number of mitochondrial ribosomes found in controls as well as fewer mitochondrial cristae. Ethidium bromide has no effect on chloroplast ultrastructure in Ochromonas. Greening cells treated with spectinomycin grow at close to control rates but contain 30-40% less chloroplast rRNA than do controls. Electron microscopy showed that spectinomycin disrupts the organization of chloroplast membranes and reduces the number of chloroplast ribosomes by 30%. Under these conditions, spectinomycin has no effect on mitochondrial rRNA or ultrastructure. Since spectinomycin is a specific inhibitor of translation on 70S ribosomes, these results are consistent with the possibility that at least some chloroplast ribosomal proteins are synthesized in the chloroplast of Ochromonas.
منابع مشابه
Effects of Chloramphenicol on Chloroplast and Mitochondrial Ultrastructure in Ochromonas Danica
The effect of chloramphenicol (CAP) on cell division and organelle ultrastructure was studied during light-induced chloroplast development in the Chrysophyte alga, Ochromonas danica. Since the growth rate of the CAP-treated cells is the same as that of the control cells for the first 12 hr in the light, CAP is presumed to be acting during that interval solely by inhibiting protein synthesis on ...
متن کاملThe Effect of NO System on Ethidium Bromide-Induced Oxidative Stress in the Hippocampal Formation of Male Rats
Background Acute and chronic effects of nitric oxide on oxidative stress and neuronal demyelination have been reported in human and animal models. Objective Oxidative stress is involved in the pathogenesis of demyelinated animals; thus, this study investigated the effects of nitric oxide system and ethidium bromide on oxidative stress in the hippocampal formation. Methods This experimental...
متن کاملThe effects of Intracerebellumal Injection of Estrogen on Anxiety-like Behavior and Parameters of Antioxidant System following Ethidium Bromide Injection in rat
Background & Objectives: Demyelination by Ethidium bromide is one of the ways that is usually used for preparing experimental models of MS. Treatment with estrogen protects oligodendrocyts from cell poisoning and stops lipidic peroxidation. The aim of this study is the evaluation of the effects of estrogen on anxiety like behavior and stress oxidative parameters after inducing demyelination by ...
متن کاملEffects of Crocin on Oxidative Stress Indices in Rat Brain Demylated with Ethidium Bromide
Background and purpose: The purpose of this study was to investigate the effects of crocin (Cr) on brain oxidative stress indices in animal model demyelinated with intracerebroventricular ethidium bromide (EB). Materials and methods: In an interventional study, female Wistar rats were randomly divided into 7 groups. Crocin administration was done 1 day after EB injection for 21 days. The value...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of cell science
دوره 43 شماره
صفحات -
تاریخ انتشار 1980