Trypanosoma brucei TBRGG1, a mitochondrial oligo(U)-binding protein that co-localizes with an in vitro RNA editing activity

• Published in: The Journal of biological chemistry Vol. 273; no. 34; pp. 21825 - 21833
• Main Authors: Vanhamme, L. (Free University of Brussels, Rhode St. Genese, Belgium.), Perez-Morga, D, Marchal, C, Speijer, D, Lambert, L, Geuskens, M, Alexandre, S, Ismaili, N, Goringer, U, Benne, R
• Format: Journal Article
• Language: English
• Published: United States 21.08.1998
• Subjects: Alternative Splicing; Amino Acid Sequence; AMINO ACID SEQUENCES; Animals; Base Sequence; BINDING PROTEINS; CHEMICAL COMPOSITION; Cloning, Molecular; COMPLEMENTARY DNA; DNA; GENBANK/Z96795; GENE EXPRESSION; GENES; IMMUNOCYTOCHEMISTRY; IMMUNOLOGY; MESSENGER RNA; MITOCHONDRIA; Mitochondria - chemistry; MOLECULAR SEQUENCE DATA; Molecular Weight; NUCLEOTIDE SEQUENCE; Poly U - metabolism; POLY(URACIL); Protein Binding; Protozoan Proteins; RNA; RNA - metabolism; RNA BINDING PROTEINS; RNA Editing; RNA, Mitochondrial; RNA, Protozoan - biosynthesis; RNA, Ribosomal - biosynthesis; RNA-Binding Proteins - genetics; RNA-Binding Proteins - metabolism; TBRGG1 GENE; TBRGG1 protein; TRYPANOSOMA BRUCEI; Trypanosoma brucei brucei - chemistry
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.273.34.21825

We report the characterization of a Trypanosoma brucei 75-kDa protein of the RGG (Arg-Gly-Gly) type, termed TBRGG1. Dicistronic and monocistronic transcripts of the TBRGG1 gene were produced by both alternative splicing and polyadenylation. TBRGG1 was found in two or three forms that differ in their electrophoretic mobility on SDS-polyacrylamide gel electrophoresis gels, one of which was more abundant in the procyclic form of the parasite. TBRGG1 was localized to the mitochondrion and appeared to be more abundant in bloodstream intermediate and stumpy forms in which the mitochondrion reactivates and during the procyclic stage, which possesses a fully functional mitochondrion. This protein was characterized to display oligo(U) binding characteristics and was found to co-localize with an in vitro RNA editing activity in a sedimentation analysis. TBRGG1 most likely corresponds to the 83-kDa oligo(U)-binding protein previously identified by UV cross-linking of guide RNA to mitochondrial lysates (Leegwater, P., Speijer, D., and Benne, R. (1995) Eur. J. Biochem. 227, 780-786).