Format

Send to

Choose Destination
J Biol Chem. 2013 Jul 5;288(27):19450-8. doi: 10.1074/jbc.M113.467670. Epub 2013 May 13.

Vitamin D receptor inhibits nuclear factor κB activation by interacting with IκB kinase β protein.

Author information

1
Laboratory of Metabolic Disease Research and Drug Development, China Medical University, Shenyang 110000, China.

Abstract

1,25-Dihydroxyvitamin D (1,25(OH)2D3) is known to suppress NF-κB activity, but the underlying mechanism remains poorly understood. Here we show that the vitamin D receptor (VDR) physically interacts with IκB kinase β (IKKβ) to block NF-κB activation. 1,25(OH)2D3 rapidly attenuates TNFα-induced p65 nuclear translocation and NF-κB activity in a VDR-dependent manner. VDR overexpression inhibits IKKβ-induced NF-κB activity. GST pull-down assays and coimmunoprecipitation experiments demonstrated that VDR physically interacts with IKKβ and that this interaction is enhanced by 1,25(OH)2D3. Protein mapping reveals that VDR-IKKβ interaction occurs between the C-terminal portions of the VDR and IKKβ proteins. Reconstitution of VDR(-/-) cells with the VDR C terminus restores the ability to block TNFα-induced NF-κB activation and IL-6 up-regulation. VDR-IKKβ interaction disrupts the formation of the IKK complex and, thus, abrogates IKKβ phosphorylation at Ser-177 and abolishes IKK activity to phosphorylate IκBα. Consequently, stabilization of IκBα arrests p65/p50 nuclear translocation. Together, these data define a novel mechanism whereby 1,25(OH)2D3-VDR inhibits NF-κB activation.

KEYWORDS:

IKKβ; Inflammation; NF-κB; Nuclear Receptors; Protein-Protein Interactions; Vitamin D

PMID:
23671281
PMCID:
PMC3707648
DOI:
10.1074/jbc.M113.467670
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center