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Pre-mRNA Splicing in Trypanosoma brucei: Factors, Mechanisms, and Regulation

Chapter
Part of the Nucleic Acids and Molecular Biology book series (NUCLEIC, volume 28)

Abstract

Processing of polycistronic pre-mRNAs in trypanosomes requires trans splicing and polyadenylation of the primary transcripts to generate mature 5′ and 3′ ends of the mRNAs, respectively. Splicing is catalyzed by the spliceosome, which contains the spliceosomal small nuclear ribonucleoprotein particles (snRNPs) U1, U2, U4/U6, and U5, as well as the SL RNP, which is essential for trans splicing. As in other eukaryotes, the trypanosomal snRNPs share a common set of seven Sm polypeptides, which assemble in a ring-like structure on the Sm binding site of the snRNAs, a process that is mediated by the survival of motor neurons (SMN) protein. Whereas studies in the last decade disclosed numerous spliceosomal components, little is known about splicing regulation in trypanosomes, even though recent studies revealed evidence for alternative trans splicing. Here we summarize the current state of research on mRNA splicing in Trypanosoma brucei which differs in several aspects from the well-studied mechanisms in other eukaryotes.

Keywords

Spinal Muscular Atrophy Tandem Affinity Purification Polypyrimidine Tract Splice Leader Trans Splice 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag GmbH Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Institute of BiochemistryJustus Liebig University of GiessenGiessenGermany
  2. 2.Department of Genetics and Developmental BiologyUniversity of Connecticut Health CenterFarmingtonUSA

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