Proteomic dissection of LPS-inducible, PHF8-dependent secretome reveals novel roles of PHF8 in TLR4-induced acute inflammation and T cell proliferation.
Endotoxin (LPS)-induced changes in histone lysine methylation contribute to the gene-specific transcription for control of inflammation. Still unidentified are the chromatin regulators that drive the transition from a transcriptional-repressive to a transcriptional-active chromatin state of pro-inflammatory genes. Here, using combined approaches to analyze LPS-induced changes in both gene-specific transcription and protein secretion to the extracellular compartment, we characterize novel functions of the lysine demethylase PHF8 as a pro-inflammatory, gene-specific chromatin regulator. First, in the LPS-induced, acute-inflamed macrophages, PHF8 knockdown led to both a reduction of pro-inflammatory factors and an increase in a transcriptional-repressive code (H3K9me2) written by the methyltransferase G9a. Through unbiased quantitative secretome screening we discovered that LPS induces the secretion of a cluster of PHF8-dependent, 'tolerizable' proteins that are related to diverse extracellular pathways/processes including those for the activation of adaptive immunity. Specifically, we determined that PHF8 promotes T-cell activation and proliferation, thus providing the first link between the epigenetic regulation of inflammation and adaptive immunity. Further, we found that, in the acute-inflamed macrophages, the acute-active PHF8 opposes the H3K9me1/2-writing activity of G9a to activate specific protein secretions that are suppressed by G9a in the endotoxin-tolerant cells, revealing the inflammatory-phenotypic chromatin drivers that regulate the gene-specific chromatin plasticity.
Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, US.
Özgün
Ö
Erdoğan
Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, US.
Ling
L
Xie
Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, US.|Department of Chemistry, Fudan University, Shanghai, China.
Li
L
Wang
Departement of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, US.
Bing
B
Wu
Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, US.
Qing
Q
Kong
Departement of Microbiology and Immunology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, US.|Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, US.
Yisong
Y
Wan
Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, US.|Department of Chemistry, Fudan University, Shanghai, China.|Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, US.
Xian
X
Chen
D000208:Acute Disease; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D049109:Cell Proliferation / Q000187:drug effects*; D018925:Chemokines / Q000235:genetics / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D044127:Epigenesis, Genetic / Q000187:drug effects; D056466:Histone Demethylases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D011495:Histone-Lysine N-Methyltransferase / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D007249:Inflammation / Q000378:metabolism / Q000473:pathology*; D008070:Lipopolysaccharides / Q000633:toxicity*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008745:Methylation / Q000187:drug effects; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism; D010748:Phosphopeptides / Q000032:analysis; D000071636:Protein Phosphatase 2C / Q000378:metabolism; D040901:Proteomics; D000067996:RAW 264.7 Cells; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000378:metabolism*; D014157:Transcription Factors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*
D018925:Chemokines; D002843:Chromatin; D016207:Cytokines; D006657:Histones; D008070:Lipopolysaccharides; D016328:NF-kappa B; D010748:Phosphopeptides; D034741:RNA, Small Interfering; D051197:Toll-Like Receptor 4; D014157:Transcription Factors; D056466:Histone Demethylases; C553256:PHF8 protein, mouse; C533711:G9a protein, mouse; D011495:Histone-Lysine N-Methyltransferase; D000071636:Protein Phosphatase 2C