NDRG2 and PRA1 interact and synergistically inhibit T-cell factor/β-catenin signaling

NDRG2 is a member of the N-myc downstream regulated gene (NDRG) family, implicated in cell growth and differentiation. Investigation of NDRG2 molecular interactions by yeast two-hybrid screening identified prenylated Rab acceptor-1 (PRA1), involved in vesicle trafficking and protein transport, as binding partner. Binding of NDRG2 (and NDRG1-4) with PRA1 in vitro was confirmed by GST pull-down assay and immunoprecipitation, and colocalization was verified by confocal microscopy in HCT116 cells. Intracellular coexpression showed that NDRG2 and PRA1 synergistically downregulate T-cell factor (TCF) promoter activity and GSK3β phosphorylation. Results suggest that NDRG2 and PRA1 might act synergistically to prevent signaling of TCF/β-catenin.Structured summary of protein interactionsNDRG2abinds to PRA1 by pull down (View interaction)NDRG2aphysically interacts with PRA1 by two hybrid (View Interaction: 1, 2)PRA1physically interacts with NDRG2a by anti tag coimmunoprecipitation (View interaction)NDRG2a, PRA1 and Catenin betacolocalize by cosedimentation (View interaction)NDRG2a and PRA1colocalize by fluorescence microscopy (View Interaction: 1, 2, 3)

► NDRG2 mRNA and protein levels are downregulated in colorectal cancer tissue.
► Yeast two-hybrid screening shows that NDRG2 and PRA1 physically interact.
► NDRG2 and PRA1 interaction is confirmed by immunoprecipitation in vitro and in vivo.
► NDRG2–PRA1 interaction inhibits TCF signaling by blocking GSK3β phosphorylation.
► NDRG2–PRA1 protein interaction downregulates cell proliferation.