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Effect of TbDRBD3 depletion on procyclic T. brucei transcriptome

ABSTRACT: In trypanosomes, the apparent lack of regulation of RNA polymerase II-dependent transcription initiation poses a challenge to understand how these eukaryotes adjust gene expression in order to adapt to the contrasting environments they find during their life cycles. Evidence so far indicates that mRNA turnover and translation are the major control points in which regulation is exerted in trypanosomes. However, very little is known about which proteins are involved, and how do they regulate the abundance and translation of different mRNAs in different life stages. In this work, an RNA-binding protein, TbDRBD3, has been identified by affinity chromatography, and its function addressed using RNA interference, microarray analysis and immunoprecipitation of mRNA-protein complexes. The results obtained indicate that TbDRBD3 binds to a subset of developmentally regulated mRNAs encoding membrane proteins and intermediate metabolism enzymes, and that this association promotes the stabilization of the target transcripts. These observations raise the possibility that TbDRBD3-mRNA complexes act as a post-transcriptional operon, and provide a framework to interpret how trypanosomes regulate gene expression in the absence of transcriptional control. Keywords: Effect of depletion of an RNA-binding protein on the transcriptome

ORGANISM(S): Trypanosoma brucei

PROVIDER: GSE8734 | GEO | 2008/07/15

SECONDARY ACCESSION(S): PRJNA101995

REPOSITORIES: GEO

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