Abstract
The transcriptional regulator STAT3 curbs pro-inflammatory cytokine production mediated by NF-κB signalling in innate immune cells, yet the mechanism by which this occurs has been unclear. Here we identify STAT3 as a pivotal negative regulator of Ubc13, an E2 ubiquitin-conjugating enzyme that facilitates TRAF6 K63-linked ubiquitination and NF-κB activation. Ubc13 accumulates intracellularly in the absence of STAT3. Depletion of Ubc13 in Stat3-deficient macrophages subdues excessive RANKL- or LPS-dependent gene expression, indicating that Ubc13 overexpression mediates enhanced transcriptional responses in the absence of STAT3. In RANKL-activated macrophages, STAT3 is stimulated by autocrine IL-6 and inhibits accrual of Ets-1, Set1 methyltransferase and trimethylation of histone H3 lysine 4 (H3K4me3) at the Ube2n (Ubc13) promoter. These results delineate a mechanism by which STAT3 operates as a transcriptional repressor on Ube2n, thus modulating NF-κB activity by regulation of Ubc13 abundance. Our data suggest that this pathway plays important roles in bone homeostasis and restraint of inflammation.
Original language | English (US) |
---|---|
Article number | 5798 |
Journal | Nature communications |
Volume | 5 |
DOIs | |
State | Published - 2014 |
ASJC Scopus subject areas
- General Chemistry
- General Biochemistry, Genetics and Molecular Biology
- General Physics and Astronomy
MD Anderson CCSG core facilities
- Advanced Technology Genomics Core
- Flow Cytometry and Cellular Imaging Facility
- Research Animal Support Facility
- Tissue Biospecimen and Pathology Resource