Mitochondrial and nucleolar localization of cysteine desulfurase Nfs and the scaffold protein Isu in Trypanosoma brucei.
Trypanosoma brucei has a complex life cycle during which its single mitochondrion is subjected to major metabolic and morphological changes. While the procyclic stage (PS) of the insect vector contains a large and reticulated mitochondrion, its counterpart in the bloodstream stage (BS) parasitizing mammals is highly reduced and seems to be devoid of most functions. We show here that key Fe-S cluster assembly proteins are still present and active in this organelle and that produced clusters are incorporated into overexpressed enzymes. Importantly, the cysteine desulfurase Nfs, equipped with the nuclear localization signal, was detected in the nucleolus of both T. brucei life stages. The scaffold protein Isu, an interacting partner of Nfs, was also found to have a dual localization in the mitochondrion and the nucleolus, while frataxin and both ferredoxins are confined to the mitochondrion. Moreover, upon depletion of Isu, cytosolic tRNA thiolation dropped in the PS but not BS parasites.
Biology Center, Institute of Parasitology, Czech Academy of Sciences and Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic.
Julie
J
Kovárová
Eva
E
Horáková
Piya
P
Changmai
Marie
M
Vancová
Julius
J
Lukeš
D021581:Active Transport, Cell Nucleus; D000595:Amino Acid Sequence; D013437:Carbon-Sulfur Lyases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism*; D005288:Ferredoxins / Q000378:metabolism; D033862:Iron-Binding Proteins / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D019913:Nuclear Localization Signals; D034521:Nuclear Matrix-Associated Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D055503:Protein Multimerization; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014346:Trypanosoma brucei brucei / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D000096923:Frataxin
D013437:Carbon-Sulfur Lyases; D005288:Ferredoxins; D033862:Iron-Binding Proteins; D024101:Mitochondrial Proteins; D019913:Nuclear Localization Signals; D034521:Nuclear Matrix-Associated Proteins; D015800:Protozoan Proteins; D000096923:Frataxin; C080546:cysteine desulfurase