Wee1 protein kinase plays an important regulatory role in cell cycle progression. It inhibits Cdc-2 activity by phosphorylating Tyr15 and arrests cells at G2-M phase. In an attempt to understand Wee1 regulation during cell cycle, yeast two-hybrid screening was used to identify Wee1-binding protein(s). Five of the eight positive clones identified encode 14-3-3beta. In vivo binding assay in 293 cells showed that both full-length and NH2-terminal truncated Wee1 bind with 14-3-3beta. The 14-3-3beta binding site was mapped to a COOH-terminal consensus motif, RSVSLT (codons 639 to 646). Binding with 14-3-3beta increases the protein level of full-length Wee1 but not of the truncated Wee1. Accompanying the protein level increases, the kinase activity of Wee1 also increases when coexpressed with 14-3-3beta. Increased Wee1 protein level/enzymatic activity is accountable, at least in part, to an increased Wee1 protein half-life when coexpressed with 14-3-3beta. The protein half-life of the NH2-terminal truncated Wee1 is much longer than that of the full-length protein and is not affected by 14-3-3beta cotransfection. Biologically, 14-3-3beta/Wee1 coexpression increases the cell population at G2-M phase. Thus, Wee1 binding with 14-3-3beta increases its biochemical activity as well as its biological function. The finding reveals a novel mechanism by which 14-3-3 regulates G2-M arrest and suggests that the NH2-terminal domain of Wee1 contains a negative regulatory sequence that determines Wee1 stability.
|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|