TitleIdentifying novel transcription factors involved in the inflammatory response by using binding site motif scanning in genomic regions defined by histone acetylation.
Publication TypeJournal Article
Year of Publication2017
AuthorsAskovich, PS, Ramsey, SA, Diercks, AH, Kennedy, KA, Knijnenburg, TA, Aderem, A
JournalPLoS One
Date Published2017
KeywordsAcetylation, Animals, Female, Gene Expression Profiling, Gene Expression Regulation, Genome, Histones, Immunity, Innate, Inflammation, Lipopolysaccharides, Macrophages, Mice, Transcription Factors

The innate immune response to pathogenic challenge is a complex, multi-staged process involving thousands of genes. While numerous transcription factors that act as master regulators of this response have been identified, the temporal complexity of gene expression changes in response to pathogen-associated molecular pattern receptor stimulation strongly suggest that additional layers of regulation remain to be uncovered. The evolved pathogen response program in mammalian innate immune cells is understood to reflect a compromise between the probability of clearing the infection and the extent of tissue damage and inflammatory sequelae it causes. Because of that, a key challenge to delineating the regulators that control the temporal inflammatory response is that an innate immune regulator that may confer a selective advantage in the wild may be dispensable in the lab setting. In order to better understand the complete transcriptional response of primary macrophages to the bacterial endotoxin lipopolysaccharide (LPS), we designed a method that integrates temporally resolved gene expression and chromatin-accessibility measurements from mouse macrophages. By correlating changes in transcription factor binding site motif enrichment scores, calculated within regions of accessible chromatin, with the average temporal expression profile of a gene cluster, we screened for transcriptional factors that regulate the cluster. We have validated our predictions of LPS-stimulated transcriptional regulators using ChIP-seq data for three transcription factors with experimentally confirmed functions in innate immunity. In addition, we predict a role in the macrophage LPS response for several novel transcription factors that have not previously been implicated in immune responses. This method is applicable to any experimental situation where temporal gene expression and chromatin-accessibility data are available.

Alternate JournalPLoS One
PubMed ID28922390
PubMed Central IDPMC5602638
Grant ListK25 HL098807 / HL / NHLBI NIH HHS / United States
R01 AI025032 / AI / NIAID NIH HHS / United States
R01 AI032972 / AI / NIAID NIH HHS / United States
U19 AI100627 / AI / NIAID NIH HHS / United States