PMID:19158487

Citation	Chen, Y, Craigen, WJ and Riley, DJ (2009) Nek1 regulates cell death and mitochondrial membrane permeability through phosphorylation of VDAC1. Cell Cycle 8:257-67
Abstract	The mammalian NIMA-related protein kinase 1 (Nek1) is important for keeping cells alive after DNA damage, but the mechanism by which injured cells die without functional Nek1 has not yet been demonstrated. Here we show that Nek1 regulates the pathway to mitochondrial cell death through phosphorylation of voltage dependent anion channel 1 (VDAC1) on serine 193. Nek1 associates with VDAC1 in a yeast two-hybrid system, as well as by GST pull-down assays and by reciprocal immunoprecipitation. A portion of Nek1 in cells also localizes at mitochondria. Ectopic expression of a kinase-dead Nek1 mutant results in cell death, which is immediately preceded by loss of the Nek1-dependent VDAC1-S193 phosphorylation. UV irradiation of Nek1-deficient cells or silencing of endogenous Nek1 expression similarly results in loss of the specific S193 phosphorylation before cells die. Nek1-deficient cells are characterized by exaggerated mitochondrial membrane permeability (MMP) and accelerated cell death. Ectopic expression of a VDAC1-Ser193Ala mutant, which cannot be phosphorylated by Nek1, also results in cell death. A VDAC1-Ser193Glu mutant, designed to mimic constitutive phosphorylation by Nek1, rescues exaggerated MMP and keeps cells alive after DNA damaging injury, but only transiently. The direct interaction between Nek1 and VDAC1 provides a mechanism to explain how Nek1 prevents excessive cell death, as well as the first direct evidence that a specific kinase regulates VDAC1 activity.
Links	PubMed PMC2673983
Keywords	Animals; Cell Cycle Proteins/genetics; Cell Cycle Proteins/metabolism; Cell Death/physiology; Cell Line, Tumor; Cell Membrane Permeability/physiology; Cells, Cultured; HeLa Cells; Humans; Membrane Potential, Mitochondrial; Mice; Mitochondrial Membranes/metabolism; Phosphorylation; Protein-Serine-Threonine Kinases/genetics; Protein-Serine-Threonine Kinases/metabolism; Voltage-Dependent Anion Channel 1/genetics; Voltage-Dependent Anion Channel 1/metabolism
edit table

Annotations

Gene product	Qualifier	GO Term	Evidence Code	with/from	Aspect	Extension	Notes	Status
HUMAN:NEK1		GO:0006468: protein phosphorylation	ECO:0000314:		P		Figure 2A.	complete CACAO 6106
HUMAN:NEK1		GO:0016301: kinase activity	ECO:0000315:		F		Figure 3.	complete CACAO 6109
HUMAN:NEK1	involved_in	GO:0006468: protein phosphorylation	ECO:0000314: direct assay evidence used in manual assertion		P		Seeded From UniProt	complete
HUMAN:NEK1	enables	GO:0016301: kinase activity	ECO:0000315: mutant phenotype evidence used in manual assertion		F		Seeded From UniProt	complete

References

See Help:References for how to manage references in GONUTS.