Post-transcriptional control of nuclear-encoded cytochrome oxidase subunits in Trypanosoma brucei: evidence for genome-wide conservation of life-cycle stage-specific regulatory elements
Open Access
- 29 September 2006
- journal article
- Published by Oxford University Press (OUP) in Nucleic Acids Research
- Vol. 34 (18), 5312-5324
- https://doi.org/10.1093/nar/gkl598
Abstract
Trypanosomes represent an excellent model for the post-transcriptional regulation of gene expression because their genome is organized into polycistronic transcription units. However, few signals governing developmental stage-specific expression have been identified, with there being no compelling evidence for widespread conservation of regulatory motifs. As a tool to search for common regulatory sequences we have used the nuclear-encoded components of the cytochrome oxidase (COX) complex of the trypanosome respiratory chain. Components of this complex represent a form of post-transcriptional operon because trypanosome mitochondrial activity is unusual in being developmentally programmed. By genome analysis we identified the genes for seven components of the COX complex. Each mRNA exhibits bloodstream stage-specific instability, which is not mediated by the RNA silencing pathway but which is alleviated by cycloheximide. Reporter assays have identified regulatory regions within the 3′-untranslated regions of three COX mRNAs operating principally at the translational level, but also via mRNA stability. Interrogation of the mapped regions via oligonucleotide frequency scoring provides evidence for genome-wide conservation of regulatory sequences among a large cohort of procyclic-enriched transcripts. Analysis of the co-regulated subunits of a stage-specific enzyme is therefore a novel approach to uncover cryptic regulatory sequences controlling gene expression at the post-transcriptional level.Keywords
This publication has 47 references indexed in Scilit:
- Functional replacement of Trypanosoma brucei Argonaute by the human slicer Argonaute2RNA, 2006
- Regulation of surface coat exchange by differentiating African trypanosomesMolecular and Biochemical Parasitology, 2006
- Regulation of antigen gene expression in Trypanosoma bruceiTrends in Parasitology, 2005
- From Birth to Death: The Complex Lives of Eukaryotic mRNAsScience, 2005
- Structure clustering features on the Sfold Web serverBioinformatics, 2005
- The Genome of the African Trypanosome Trypanosoma bruceiScience, 2005
- Involvement of MicroRNA in AU-Rich Element-Mediated mRNA InstabilityCell, 2005
- Extensive Association of Functionally and Cytotopically Related mRNAs with Puf Family RNA-Binding Proteins in YeastPLoS Biology, 2004
- Extracting regulatory sites from the upstream region of yeast genes by computational analysis of oligonucleotide frequencies 1 1Edited by G. von HeijneJournal of Molecular Biology, 1998
- Polysomal, procyclin mRNAs accumulate in bloodstream forms of monomorphic and pleomorphic trypanosomes treated with protein synthesis inhibitorsMolecular and Biochemical Parasitology, 1996