Skip Navigation
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Your Environment. Your Health.

Publication Detail

Title: Circadian control of innate immunity in macrophages by miR-155 targeting Bmal1.

Authors: Curtis, Anne M; Fagundes, Caio T; Yang, Guangrui; Palsson-McDermott, Eva M; Wochal, Paulina; McGettrick, Anne F; Foley, Niamh H; Early, James O; Chen, Lihong; Zhang, Hanrui; Xue, Chenyi; Geiger, Sarah S; Hokamp, Karsten; Reilly, Muredach P; Coogan, Andrew N; Vigorito, Elena; FitzGerald, Garret A; O'Neill, Luke A J

Published In Proc Natl Acad Sci U S A, (2015 Jun 09)

Abstract: The response to an innate immune challenge is conditioned by the time of day, but the molecular basis for this remains unclear. In myeloid cells, there is a temporal regulation to induction by lipopolysaccharide (LPS) of the proinflammatory microRNA miR-155 that correlates inversely with levels of BMAL1. BMAL1 in the myeloid lineage inhibits activation of NF-κB and miR-155 induction and protects mice from LPS-induced sepsis. Bmal1 has two miR-155-binding sites in its 3'-UTR, and, in response to LPS, miR-155 binds to these two target sites, leading to suppression of Bmal1 mRNA and protein in mice and humans. miR-155 deletion perturbs circadian function, gives rise to a shorter circadian day, and ablates the circadian effect on cytokine responses to LPS. Thus, the molecular clock controls miR-155 induction that can repress BMAL1 directly. This leads to an innate immune response that is variably responsive to challenges across the circadian day.

PubMed ID: 25995365 Exiting the NIEHS site

MeSH Terms: 3' Untranslated Regions; ARNTL Transcription Factors/genetics; ARNTL Transcription Factors/physiology*; Adipose Tissue/metabolism; Animals; Circadian Rhythm*; Cytokines/biosynthesis; Immunity, Innate*; Macrophages/immunology*; Macrophages/metabolism; Mice; Mice, Knockout; MicroRNAs/physiology*; NF-kappa B/metabolism

to Top