Eukaryotic gene expression requires the export of mRNA from nucleus to the cytoplasm. The DEAD box protein Dbp5p is an essential export factor conserved from yeast to man. A fraction of Dbp5p forms a complex with nucleoporins of the cytoplasmic filaments of the nuclear pore complex (NPC). Gfd1p was identified originally as a multicopy suppressor of the rat8-2 ts allele of DBP5. Here we report that Dbp5p and Gfd1p interact with Zds1p, a protein previously identified as a multicopy suppressor in several yeast genetic screens. Using the 2-hybrid system we show that Zds1p interacts in vivo with both Gfd1p and Dbp5p. In vitro binding experiments reveal that Gfd1p and Dbp5p bind directly to the C-terminal part of Zds1p. In addition, ZDS1 interacts genetically with mutant alleles of genes encoding key factors in mRNA export, including DBP5 and MEX67. Furthermore, deletion of ZDS1 or of both ZDS1 and the closely-related ZDS2 exacerbates the poly(A)+ export defects shown by dbp5-2 and mex67-5 mutants. We propose that Zds1p associates with the complex formed by Dbp5p, Gfd1p, and nucleoporins at the cytosolic fibrils of the NPC and is required for optimal mRNA export.
|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|