Interaction of ZPR1 with translation elongation factor-1alpha in proliferating cells
UMass Chan Affiliations
Howard Hughes Medical Institute and Program in Molecular MedicineDocument Type
ArticlePublication Date
1998-12-16Keywords
Amino Acid SequenceAnimals
COS Cells
Carrier Proteins
Cell Cycle
Cell Division
Cell Line
Consensus Sequence
Fungal Proteins
G2 PhaseGene DeletionGenes, FungalGenotypeHumansMammalsMiceMitosisMolecular Sequence DataPeptide Elongation Factor 1Peptide Elongation FactorsRecombinant ProteinsRestriction MappingSaccharomyces cerevisiae*Saccharomyces cerevisiae ProteinsSchizosaccharomycesSequence AlignmentSequence Homology, Amino AcidZinc FingersCell Biology
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The zinc finger protein ZPR1 is present in the cytoplasm of quiescent mammalian cells and translocates to the nucleus upon treatment with mitogens, including epidermal growth factor (EGF). Homologues of ZPR1 were identified in yeast and mammals. These ZPR1 proteins bind to eukaryotic translation elongation factor-1alpha (eEF-1alpha). Studies of mammalian cells demonstrated that EGF treatment induces the interaction of ZPR1 with eEF-1alpha and the redistribution of both proteins to the nucleus. In the yeast Saccharomyces cerevisiae, genetic analysis demonstrated that ZPR1 is an essential gene. Deletion analysis demonstrated that the NH2-terminal region of ZPR1 is required for normal growth and that the COOH-terminal region was essential for viability in S. cerevisiae. The yeast ZPR1 protein redistributes from the cytoplasm to the nucleus in response to nutrient stimulation. Disruption of the binding of ZPR1 to eEF-1alpha by mutational analysis resulted in an accumulation of cells in the G2/M phase of cell cycle and defective growth. Reconstitution of the ZPR1 interaction with eEF-1alpha restored normal growth. We conclude that ZPR1 is essential for cell viability and that its interaction with eEF-1alpha contributes to normal cellular proliferation.Source
J Cell Biol. 1998 Dec 14;143(6):1471-84.Permanent Link to this Item
http://hdl.handle.net/20.500.14038/42605PubMed ID
9852145Related Resources
Link to Article in PubMedCollections
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