Journal article

Publication year: 2000

Pages: 8967-8972

Journal: Proceedings of the National Academy of Sciences

Volume number: 97

Issue number: 16

ISSN: 0027-8424

eISSN: 1091-6490

Open access status: Green

DOI Link: https://doi.org/10.1073/pnas.150236097

Publisher: National Academy of Sciences

Abstract: 
Each of the trypanosome small nuclear ribonucleoproteins (snRNPs) U2, U4/U6, and U5, as well as the spliced leader (SL) RNP, contains a core of common proteins, which we have previously identified. This core is unusual because it is not recognized by anti-Sm Abs and it associates with an Sm-related sequence in the trypanosome small nuclear RNAs (snRNAs). Using peptide sequences derived from affinity-purified U2 snRNP proteins, we have cloned cDNAs for five common proteins of 8.5, 10, 12.5, 14, and 15 kDa of Trypanosoma brucei and identified them as Sm proteins SmF (8.5 kDa), -E (10 kDa), -D1 (12.5 kDa), -G (14 kDa), and -D2 (15 kDa), respectively. Furthermore, we found the trypanosome SmB (T. brucei) and SmD3 (Trypanosoma cruzi) homologues through database searches, thus completing a set of seven canonical Sm proteins. Sequence comparisons of the trypanosome proteins revealed several deviations in highly conserved positions from the Sm consensus motif. We have identified a network of specific heterodimeric and -trimeric Sm protein interactions in vitro. These results are summarized in a model of the trypanosome Sm core, which argues for a strong conservation of the Sm particle structure. The conservation extends also to the functional level, because at least one trypanosome Sm protein, SmG, was able to specifically complement a corresponding mutation in yeast.

Harvard Citation style: Palfi, Z., Lücke, S., Lahm, H., Lane, W., Kruft, V., Bragado-Nilsson, E., et al. (2000) The spliceosomal snRNP core complex of Trypanosoma brucei: Cloning and functional analysis reveals seven Sm protein constituents, Proceedings of the National Academy of Sciences, 97(16), pp. 8967-8972. https://doi.org/10.1073/pnas.150236097

APA Citation style: Palfi, Z., Lücke, S., Lahm, H., Lane, W., Kruft, V., Bragado-Nilsson, E., Seraphin, B., & Bindereif, A. (2000). The spliceosomal snRNP core complex of Trypanosoma brucei: Cloning and functional analysis reveals seven Sm protein constituents. Proceedings of the National Academy of Sciences. 97(16), 8967-8972. https://doi.org/10.1073/pnas.150236097