title: CK2 functionally interacts with AKT/PKB to promote the β-catenin-dependent expression of survivin and enhance cell survival.
abstract: β-Catenin is crucial in the canonical Wnt signaling pathway. This pathway is up-regulated by CK2 which is associated with an enhanced expression of the antiapoptotic protein survivin, although the underlying molecular mechanism is unknown. AKT/PKB kinase phosphorylates and promotes β-catenin transcriptional activity, whereas CK2 hyperactivates AKT by phosphorylation at Ser129; however, the role of this phosphorylation on β-catenin transcriptional activity and cell survival is unclear. We studied in HEK-293T cells, the effect of CK2-dependent hyperactivation of AKT on cell viability, as well as analyzed β-catenin subcellular localization and transcriptional activity and survivin expression. CK2α overexpression led to an augmented β-catenin-dependent transcription and protein levels of survivin, and consequently an enhanced resistance to apoptosis. However, CK2α-enhancing effects were reversed when an AKT mutant deficient in Ser129 phosphorylation by CK2 was co-expressed. Therefore, our results strongly suggest that CK2α-specific enhancement of β-catenin transcriptional activity as well as cell survival may depend on AKT hyperactivation by CK2.
authors: Institute of Biomedical Sciences, Cell Transformation Laboratory, Program of Cellular and Molecular Biology, ICBM, University of Chile, Av. Independencia 1027, 8700664 Santiago, Chile.
authors: Daniela P
authors: DP
authors: Ponce
authors: Roger
authors: R
authors: Yefi
authors: Pablo
authors: P
authors: Cabello
authors: Jose L
authors: JL
authors: Maturana
authors: Ignacio
authors: I
authors: Niechi
authors: Eduardo
authors: E
authors: Silva
authors: Mario
authors: M
authors: Galindo
authors: Marcelo
authors: M
authors: Antonelli
authors: Katherine
authors: K
authors: Marcelain
authors: Ricardo
authors: R
authors: Armisen
authors: Julio C
authors: JC
authors: Tapia
mesh_terms: D017209:Apoptosis; D047390:Casein Kinase II / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D002470:Cell Survival; D057809:HEK293 Cells; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000378:metabolism*; D050505:Mutant Proteins / Q000378:metabolism; D010766:Phosphorylation; D011485:Protein Binding; D021381:Protein Transport; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D015854:Up-Regulation; D051176:beta Catenin / Q000378:metabolism*
chemical_list: D051034:Inhibitor of Apoptosis Proteins; D050505:Mutant Proteins; D051176:beta Catenin; D047390:Casein Kinase II; D051057:Proto-Oncogene Proteins c-akt