Formation of a ribonucleoprotein particle (mRNP) competent for export requires the coupling of transcription with mRNA processing and RNA export. A key link between these processes is provided by the THO complex. To progress into our understanding of this coupling we have performed a search for suppressors of the transcription defect of hpr1Delta. This has permitted to identify mutations in the genes of the RNAPII Mediator component Med10, the Sch9 protein-kinase and the Ypr045c protein. We report a role in transcription elongation for Ypr045c (Thp3) and the Csn12 component of the COP9-signalosome. Thp3 and Csn12 form a complex that is recruited to transcribed genes. Their mutations suppress the gene expression defects of mutants of the THO complex involved in mRNP biogenesis and export and show defects in mRNA accumulation. Transcription elongation impairment of thp3Delta mutants is shown by in vivo transcript run on analysis performed in G-less systems. Thp3-Csn12 establishes a novel link between transcription and mRNA processing that open new perspectives to our understanding of gene expression and reveals novel functions for a component of the COP9-signalosome. Thp3-Csn12 also co-purifies with ribosomal proteins, which opens the possibility that it might have other functions in addition to transcription.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Reference||Annotation Extension|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Conditions||Strain||Source||Reference|