RNA Metabolism in Trypanosomes: Approaches to Unravel pre-mRNA Signals Required for Intron Removal

  • Christian Tschudi
  • Elisabetta Ullu


The study of RNA metabolism in trypanosomes has provided the scientific community with a number of unexpected and enticing discoveries, including polycistronic transcription (Ullu et al., 1996), trans-splicing (Ullu et al., 1996), cap 4 modification (Bangs et al., 1992), mitochondrial RNA editing (Hajduk et al., 1997; Simpson and Emeson, 1996; Stuart et al., 1997), coupling of trans-splicing and polyadenylation (Matthews et al., 1994), and more recently RNA interference or RNAi (Ngo et al., 1998). Furthermore, over the past few years we have learned that there is very little, if any, regulation of gene expression at the transcriptional level and that most likely modulation of gene expression is achieved primarily at the post-transcriptional level. In this scenario, the pre-mRNA cis-acting signals for RNA processing, by virtue of their interactions with processing machineries, would be major determinants for regulating gene expression.


Polymerase Chain Reaction Splice Site Polymerase Chain Reaction Reaction Polymerase Chain Reaction Fragment Trypanosoma Brucei 
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Copyright information

© Springer Science+Business Media New York 2000

Authors and Affiliations

  • Christian Tschudi
    • 1
  • Elisabetta Ullu
    • 1
  1. 1.Department of Internal MedicineYale University School of MedicineNew HavenUSA

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