TU Darmstadt / ULB / TUbiblio

Trypanosoma brucei mitochondrial ribonucleoprotein complexes which contain 12S and 9S ribosomal RNAs.

Shu, H. H. ; Göringer, H. Ulrich (1998)
Trypanosoma brucei mitochondrial ribonucleoprotein complexes which contain 12S and 9S ribosomal RNAs.
In: Parasitology, 116 (2)
Artikel, Bibliographie

Kurzbeschreibung (Abstract)

Antibiotics have been widely used to identify ribosomal activity in Trypanosoma brucei mitochondria. The validity of some of the results has been questioned because the permeability of the trypanosome cell membrane for some antibiotics was not adequately addressed. Here we describe translation inhibition experiments with digitonin-permeabilized trypanosomes to exclude diffusion barriers through the cell membrane. Using this system we were able to confirm, next to the eukaryotic and thus cycloheximide-sensitive translation system, the existence of a prokaryotic-type translational activity being cycloheximide resistant, chloramphenicol sensitive and streptomycin dependent. We interpret this observation analogous to what has been found for other eukarya as the independent protein synthesis activity of the mitochondrial organelle. We further examined the putative translational apparatus by using isokinetic density-gradient analysis of mitochondrial extracts. The 2 mitochondrially encoded rRNAs, the 9S and 12S rRNAs, were found to co-fractionate in a single RNP complex, approximately 80S in size. This complex disassembled at reduced MgCl2 concentrations into 2 unusually small complexes of 17.5S, containing the 9S rRNA, and 20S containing the 12S rRNA. A preliminary stoichiometry determination suggested a multicopy assembly of these putative subunits in a 2:3 ratio (20S:17.5S).

Typ des Eintrags: Artikel
Erschienen: 1998
Autor(en): Shu, H. H. ; Göringer, H. Ulrich
Art des Eintrags: Bibliographie
Titel: Trypanosoma brucei mitochondrial ribonucleoprotein complexes which contain 12S and 9S ribosomal RNAs.
Sprache: Englisch
Publikationsjahr: 1998
Titel der Zeitschrift, Zeitung oder Schriftenreihe: Parasitology
Jahrgang/Volume einer Zeitschrift: 116
(Heft-)Nummer: 2
Kurzbeschreibung (Abstract):

Antibiotics have been widely used to identify ribosomal activity in Trypanosoma brucei mitochondria. The validity of some of the results has been questioned because the permeability of the trypanosome cell membrane for some antibiotics was not adequately addressed. Here we describe translation inhibition experiments with digitonin-permeabilized trypanosomes to exclude diffusion barriers through the cell membrane. Using this system we were able to confirm, next to the eukaryotic and thus cycloheximide-sensitive translation system, the existence of a prokaryotic-type translational activity being cycloheximide resistant, chloramphenicol sensitive and streptomycin dependent. We interpret this observation analogous to what has been found for other eukarya as the independent protein synthesis activity of the mitochondrial organelle. We further examined the putative translational apparatus by using isokinetic density-gradient analysis of mitochondrial extracts. The 2 mitochondrially encoded rRNAs, the 9S and 12S rRNAs, were found to co-fractionate in a single RNP complex, approximately 80S in size. This complex disassembled at reduced MgCl2 concentrations into 2 unusually small complexes of 17.5S, containing the 9S rRNA, and 20S containing the 12S rRNA. A preliminary stoichiometry determination suggested a multicopy assembly of these putative subunits in a 2:3 ratio (20S:17.5S).

Fachbereich(e)/-gebiet(e): 10 Fachbereich Biologie > Genregulation und RNA-Therapeutika
?? fb10_mikrobiologie ??
10 Fachbereich Biologie
Hinterlegungsdatum: 03 Nov 2011 13:21
Letzte Änderung: 05 Mär 2013 09:55
PPN:
Export:
Suche nach Titel in: TUfind oder in Google
Frage zum Eintrag Frage zum Eintrag

Optionen (nur für Redakteure)
Redaktionelle Details anzeigen Redaktionelle Details anzeigen