title: [The origin of mitochondrial RNA in animal tissues. 4. Post-transcriptional RNA modification and polyribosome formation in isolated mitochondria].
abstract: The kinetics of synthesis of various mitochondrial RNA classes and their contribution to polyribosome formation was studied in isolated rat liver mitochondria and in inner membrane fraction obrained from the latter. In pulse labelling experiments it was shown that mitochondrial mRNA synthesis occurred via heavy precursor (30S) not bound to polysomes followed by maturation of polysome-bound mRNA. The time course of polysomal mRNA decay in isolated mitochondria and of protein synthesis inactivation were studied under actinomycin D blockage of mitochondrial DNA trascription. The functional organization of transcriptional units of the mitochondrial genome is discussed in relation to the data obtained.
mesh_terms: D000818:Animals; D005796:Genes; D007700:Kinetics; D008930:Mitochondria, Liver / Q000378:metabolism*; D009694:Nucleic Acid Precursors / Q000378:metabolism; D011132:Polyribosomes / Q000378:metabolism* / Q000648:ultrastructure; D012313:RNA / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D014158:Transcription, Genetic
chemical_list: D009694:Nucleic Acid Precursors; D012333:RNA, Messenger; D012313:RNA
vernacular_title: Proiskhozhdenie RNK mitokhondriĭ zhivotnykh tkaneĭ. IV. Posttranskriptsionnaia modifikatsiia RNK i obrazovanie poliribosom v izolirovannykh mitokhondriiakh