Myeloid-derived cullin 3 promotes STAT3 phosphorylation by inhibiting OGT expression and protects against intestinal inflammation.

ABSTRACT: Signal transducer and activator of transcription 3 (STAT3) is a key mediator of intestinal inflammation and tumorigenesis. However, the molecular mechanism that modulates STAT3 phosphorylation and activation is not fully understood. Here, we demonstrate that modification of STAT3 with O-linked β-N-acetylglucosamine (O-GlcNAc) on threonine 717 (T717) negatively regulates its phosphorylation and targets gene expression in macrophages. We further found that cullin 3 (CUL3), a cullin family E3 ubiquitin ligase, down-regulates the expression of the O-GlcNAc transferase (OGT) and inhibits STAT3 O-GlcNAcylation. The inhibitory effect of CUL3 on OGT expression is dependent on nuclear factor E2-related factor-2 (Nrf2), which binds to the Ogt promoter region

SUBMITTER: Li X 

PROVIDER: S-EPMC5379975 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature