Gene expression regulatory networks in Trypanosoma brucei: insights into the role of the mRNA-binding proteome

Mol Microbiol. 2016 May;100(3):457-71. doi: 10.1111/mmi.13328. Epub 2016 Mar 10.

Abstract

Control of gene expression at the post-transcriptional level is essential in all organisms, and RNA-binding proteins play critical roles from mRNA synthesis to decay. To fully understand this process, it is necessary to identify the complete set of RNA-binding proteins and the functional consequences of the protein-mRNA interactions. Here, we provide an overview of the proteins that bind to mRNAs and their functions in the pathogenic bloodstream form of Trypanosoma brucei. We describe the production of a small collection of open-reading frames encoding proteins potentially involved in mRNA metabolism. With this ORFeome collection, we used tethering to screen for proteins that play a role in post-transcriptional control. A yeast two-hybrid screen showed that several of the discovered repressors interact with components of the CAF1/NOT1 deadenylation complex. To identify the RNA-binding proteins, we obtained the mRNA-bound proteome. We identified 155 high-confidence candidates, including many not previously annotated as RNA-binding proteins. Twenty seven of these proteins affected reporter expression in the tethering screen. Our study provides novel insights into the potential trypanosome mRNPs composition, architecture and function.

MeSH terms

  • Gene Expression Profiling
  • Gene Expression Regulation
  • Gene Regulatory Networks
  • High-Throughput Screening Assays
  • Proteome / genetics*
  • Protozoan Proteins / analysis
  • Protozoan Proteins / genetics*
  • Protozoan Proteins / metabolism
  • RNA, Messenger / genetics*
  • RNA, Protozoan / genetics*
  • RNA-Binding Proteins / analysis
  • RNA-Binding Proteins / genetics*
  • RNA-Binding Proteins / metabolism
  • Trypanosoma brucei brucei / genetics*

Substances

  • Proteome
  • Protozoan Proteins
  • RNA, Messenger
  • RNA, Protozoan
  • RNA-Binding Proteins