This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Miller, S I Articles by Wirth, D F Search for Related Content PubMed PubMed Citation Articles by Miller, S I Articles by Wirth, D F

 Previous Article  |  Next Article 

Mol Cell Biol. 1988 June; 8(6): 2597-2603

trans splicing in Leishmania enriettii and identification of ribonucleoprotein complexes containing the spliced leader and U2 equivalent RNAs.

Department of Tropical Public Health, Harvard School of Public Health, Boston, Massachusetts 02115.

ABSTRACT

The 5' ends of Leishmania mRNAs contain an identical 35-nucleotide sequence termed the spliced leader (SL) or 5' mini-exon. The SL sequence is at the 5' end of an 85-nucleotide primary transcript that contains a consensus eucaryotic 5' intron-exon splice junction immediately 3' to the SL. The SL is added to protein-coding genes immediately 3' to a consensus eucaryotic 3' intron-exon splice junction. Our previous work demonstrated possible intermediates in discontinuous mRNA processing that contain the 50 nucleotides of the SL primary transcript 3' to the SL, the SL intron sequence (SLIS). These RNAs have a 5' terminus at the splice junction of the SL and the SLIS. We examined a Leishmania nuclear extract for these RNAs in ribonucleoprotein (RNP) particles. Density centrifugation analysis showed that the SL RNA is predominantly in RNP complexes at 60S, while the SLIS-containing RNAs are in complexes at 40S. We also demonstrated that the SLIS can be released from polyadenylated RNA by incubation with a HeLa cell extract containing debranching enzymatic activity. These data suggested that Leishmania enriettii mRNAs are assembled by bimolecular or trans splicing as has been recently demonstrated for Trypanosoma brucei. Furthermore, we determined the partial sequence of the Leishmania U2 equivalent RNA and demonstrated that it cosediments with the SL RNA at 60S in a nuclear extract. These RNP particles may be analogous to so-called spliceosomes that have been demonstrated in other systems.

This article has been cited by other articles:

• Kelly, B. L., Stetson, D. B., Locksley, R. M. (2003). Leishmania major LACK Antigen Is Required for Efficient Vertebrate Parasitization. J. Exp. Med. 198: 1689-1698 [Abstract] [Full Text]  
• Jardim, A., Bergeson, S. E., Shih, S., Carter, N., Lucas, R. W., Merlin, G., Myler, P. J., Stuart, K., Ullman, B. (1999). Xanthine Phosphoribosyltransferase from Leishmania donovani. MOLECULAR CLONING, BIOCHEMICAL CHARACTERIZATION, AND GENETIC ANALYSIS. J. Biol. Chem. 274: 34403-34410 [Abstract] [Full Text]  
• Ferguson, K. C., Rothman, J. H. (1999). Alterations in the Conserved SL1 trans-Spliced Leader of Caenorhabditis elegans Demonstrate Flexibility in Length and Sequence Requirements In Vivo. Mol. Cell. Biol. 19: 1892-1900 [Abstract] [Full Text]  
• Hartshorne, T, Agabian, N (1990). A new U2 RNA secondary structure provided by phylogenetic analysis of trypanosomatid U2 RNAs.. Genes Dev. 4: 2121-2131 [Abstract]