title: Gαi1 and Gαi3 regulate macrophage polarization by forming a complex containing CD14 and Gab1.
abstract: Heterotrimeric G proteins have been implicated in Toll-like receptor 4 (TLR4) signaling in macrophages and endothelial cells. However, whether guanine nucleotide-binding protein G(i) subunit alpha-1 and alpha-3 (Gαi1/3) are required for LPS responses remains unclear, and if so, the underlying mechanisms need to be studied. In this study, we demonstrated that, in response to LPS, Gαi1/3 form complexes containing the pattern recognition receptor (PRR) CD14 and growth factor receptor binding 2 (Grb2)-associated binding protein (Gab1), which are required for activation of PI3K-Akt signaling. Gαi1/3 deficiency decreased LPS-induced TLR4 endocytosis, which was associated with decreased phosphorylation of IFN regulatory factor 3 (IRF3). Gαi1/3 knockdown in bone marrow-derived macrophage cells (Gαi1/3 KD BMDMs) exhibited an M2-like phenotype with significantly suppressed production of TNF-α, IL-6, IL-12, and NO in response to LPS. The altered polarization coincided with decreased Akt activation. Further, Gαi1/3 deficiency caused LPS tolerance in mice. In vitro studies revealed that, in LPS-tolerant macrophages, Gαi1/3 were down-regulated partially by the proteasome pathway. Collectively, the present findings demonstrated that Gαi1/3 can interact with CD14/Gab1, which modulates macrophage polarization in vitro and in vivo.
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Xianjing
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Duowei
authors.initials: D
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Zhen
authors.initials: Z
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Ermei
authors.initials: E
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Jingjing
authors.initials: J
authors.lastname: Duan
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Wei
authors.initials: W
authors.lastname: Tian
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Linjun
authors.initials: L
authors.lastname: You
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Yulian
authors.initials: Y
authors.lastname: Zou
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Yan
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: Department of Urology, Jiangsu Province Hospital of Traditional Chinese Medicine, Nanjing 210029, China;
authors.forename: Qingyi
authors.initials: Q
authors.lastname: Zhu
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Changhai Hospital, Second Military Medical University, Shanghai 200433, China; and.
authors.forename: Xiaojian
authors.initials: X
authors.lastname: Wan
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China;
authors.forename: Tao
authors.initials: T
authors.lastname: Xi
authors.affiliation: Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA 90095;
authors.forename: Meisheng
authors.initials: M
authors.lastname: Jiang
authors.affiliation: Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
authors.forename: Yuyuan
authors.initials: Y
authors.lastname: Han
authors.affiliation: Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912
authors.forename: Cong
authors.initials: C
authors.lastname: Cao
authors.affiliation: Laboratory of Neurobiology, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709 yy@cpu.edu.cn birbau1@gmail.com.
authors.forename: Lutz
authors.initials: L
authors.lastname: Birnbaumer
authors.affiliation: Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02912|University of Hawaii Cancer Center, Honolulu, HI 96813
authors.forename: Wen-Ming
authors.initials: WM
authors.lastname: Chu
authors.affiliation: State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Disease, Center for New Drug Safety Evaluation and Research, China Pharmaceutical University, Nanjing 211198, China; yy@cpu.edu.cn birbau1@gmail.com.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D004705:Endocytosis / Q000187:drug effects; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D018664:Interleukin-12 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D018950:Lipopolysaccharide Receptors / Q000235:genetics / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000378:metabolism; D057507:Mice, 129 Strain; D018345:Mice, Knockout; D018613:Microscopy, Confocal; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis; D051197:Toll-Like Receptor 4 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C490897:Gab1 protein, mouse; D015850:Interleukin-6; D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D010750:Phosphoproteins; D021122:Protein Subunits; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha; D018664:Interleukin-12; D020928:Mitogen-Activated Protein Kinases; D019206:GTP-Binding Protein alpha Subunits, Gi-Go
keywords: Gαi1; Gαi3; Toll-like receptor 4; endosome; macrophage polarization
references.citation: Proc Natl Acad Sci U S A. 2003 Jul 8;100(14):8270-5
references.pmid: 12826607
references.citation: Nat Med. 2014 Sep;20(9):1001-8
references.pmid: 25086906
references.citation: Shock. 2004 Jul;22(1):57-62
references.pmid: 15201703
references.citation: J Virol. 1991 Dec;65(12):6872-80
references.pmid: 1658380
references.citation: Nat Genet. 1995 Jun;10(2):143-50
references.pmid: 7663509
references.citation: Biochim Biophys Acta. 1996 Jun 13;1312(2):163-8
references.pmid: 8672540
references.citation: J Clin Invest. 1998 Dec 1;102(11):2019-27
references.pmid: 9835628
references.citation: Shock. 1999 May;11(5):330-5
references.pmid: 10353538
references.citation: Nature. 1999 Sep 2;401(6748):82-5
references.pmid: 10485710
references.citation: Br J Pharmacol. 2006 Jan;147 Suppl 1:S46-55
references.pmid: 16402120
references.citation: Cell. 2006 Jul 14;126(1):25-7
references.pmid: 16839871
references.citation: Circ Res. 2006 Dec 8;99(12):1305-14
references.pmid: 17158346
references.citation: Biochemistry. 2007 Jul 3;46(26):7665-77
references.pmid: 17559193
references.citation: Immunology. 2007 Sep;122(1):116-23
references.pmid: 17484771
references.citation: Nat Immunol. 2008 Apr;9(4):361-8
references.pmid: 18297073
references.citation: Immunol Rev. 2008 Apr;222:155-61
references.pmid: 18364000
references.citation: Cell. 2008 Oct 3;135(1):61-73
references.pmid: 18854155
references.citation: Nat Rev Immunol. 2008 Dec;8(12):958-69
references.pmid: 19029990
references.citation: Sci Signal. 2009;2(68):ra17
references.pmid: 19401591
references.citation: Blood. 2009 Oct 8;114(15):3316-24
references.pmid: 19657115
references.citation: Proc Natl Acad Sci U S A. 2010 Feb 9;107(6):2568-73
references.pmid: 20133793
references.citation: Annu Rev Physiol. 2010;72:219-46
references.pmid: 20148674
references.citation: J Biol Chem. 2010 May 14;285(20):15268-77
references.pmid: 20231290
references.citation: Cell. 2000 Sep 1;102(5):635-46
references.pmid: 11007482
references.citation: Proc Natl Acad Sci U S A. 2001 Mar 13;98(6):3577-82
references.pmid: 11248120
references.citation: Nat Immunol. 2001 Apr;2(4):338-45
references.pmid: 11276205
references.citation: FEBS Lett. 2002 Mar 27;515(1-3):1-7
references.pmid: 11943184
references.citation: J Immunol. 2010 Jun 1;184(11):6447-56
references.pmid: 20435932
references.citation: Biochim Biophys Acta. 2011 Mar;1813(3):466-72
references.pmid: 21255617
references.citation: Cell. 2011 Nov 11;147(4):868-80
references.pmid: 22078883
references.citation: Am J Physiol Heart Circ Physiol. 2011 Dec;301(6):H2246-53
references.pmid: 21949112
references.citation: J Clin Invest. 2012 Mar;122(3):787-95
references.pmid: 22378047
references.citation: Nat Immunol. 2012 Jul;13(7):642-50
references.pmid: 22610140
references.citation: Inflammation. 2012 Oct;35(5):1611-7
references.pmid: 22581266
references.citation: J Immunol. 2013 Jan 1;190(1):324-33
references.pmid: 23225882
references.citation: Nature. 2013 Apr 25;496(7446):445-55
references.pmid: 23619691
references.citation: Nature. 2013 May 9;497(7448):211-6
references.pmid: 23636330
references.citation: PLoS One. 2014;9(1):e85834
references.pmid: 24465735
references.citation: Mol Cell Biol. 2004 Feb;24(4):1531-9
references.pmid: 14749370