TY - JOUR
T1 - Comprehensive RNAi-based screening of human and mouse TLR pathways identifies species-specific preferences in signaling protein use
AU - Sun, Jing
AU - Li, Ning
AU - Oh, Kyu Seon
AU - Dutta, Bhaskar
AU - Vayttaden, Sharat J.
AU - Lin, Bin
AU - Ebert, Thomas S.
AU - De Nardo, Dominic
AU - Davis, Joie
AU - Bagirzadeh, Rustam
AU - Lounsbury, Nicolas W.
AU - Pasare, Chandrashekhar
AU - Latz, Eicke
AU - Hornung, Veit
AU - Fraser, Iain D C
N1 - Funding Information:
We thank R. Germain, R. Gottschalk, and colleagues in the Laboratory of Systems Biology for helpful discussions and critical reading of the manuscript; S. Holland for assistance in obtaining blood from an IRAK4-deficient patient; X. Li for provision of the human IRAK4 kinase-deficient mutant; A. Miller for assistance with the bacterial infection assay; and R. Stahl for assistance in generating the mouse IRAK4-mCitrine retroviral plasmids. This work was supported by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases (NIAID) (to J.S., N.L., K.-S.O., B.D., S.J.V., B.L., J.D., N.W.L., and I.D.C.F.) and the BONFOR research commission at the University of Bonn (to D.D.N.). V.H. and T.S.E. are supported by grants from the German Research Foundation (SFB704 and SFB670) and the European Research Council (ERC- 2009-StG 243046). E.L. is supported by grants from the NIH (R01HL112661), the Deutsche Forschungsgemeinschaft (SFB670), and the European Research Council (ERCInflammAct). E.L. and V.H. are members of the ImmunoSensation cluster of excellence. C.P. is supported by grants from the NIAID (AI082265) and The Welch Foundation (I-1820). R.B. is supported by an NIH Integrative Immunology Training program grant (5T32-AI005284-35).
PY - 2016/1/5
Y1 - 2016/1/5
N2 - Toll-like receptors (TLRs) are a major class of pattern recognition receptors, whichmediate the responses of innate immune cells to microbial stimuli. To systematically determine the roles of proteins in canonical TLR signaling pathways, we conducted an RNA interference (RNAi)-based screen in human and mouse macrophages. We observed a pattern of conserved signaling module dependencies across species, but found notable species-specific requirements at the level of individual proteins. Among these, weidentified unexpected differences in the involvement of members of the interleukin-1 receptor-associated kinase (IRAK) family between the human andmouse TLR pathways. Whereas TLR signaling inmousemacrophages depended primarily on IRAK4 and IRAK2, with little or no role for IRAK1, TLR signaling and proinflammatory cytokine production in human macrophages depended on IRAK1, with knockdown of IRAK4 or IRAK2 having less of an effect. Consistent with species-specific roles for these kinases, IRAK4 orthologs failed to rescue signaling in IRAK4-deficient macrophages from the other species, and only mouse macrophages required the kinase activity of IRAK4 to mediate TLR responses. The identification of a critical role for IRAK1 in TLR signaling in humans could potentially explain the association of IRAK1 with several autoimmune diseases. Furthermore, this study demonstrated how systematic screening can be used to identify important characteristics of innate immune responses across species, which could optimize therapeutic targeting to manipulate human TLR-dependent outputs.
AB - Toll-like receptors (TLRs) are a major class of pattern recognition receptors, whichmediate the responses of innate immune cells to microbial stimuli. To systematically determine the roles of proteins in canonical TLR signaling pathways, we conducted an RNA interference (RNAi)-based screen in human and mouse macrophages. We observed a pattern of conserved signaling module dependencies across species, but found notable species-specific requirements at the level of individual proteins. Among these, weidentified unexpected differences in the involvement of members of the interleukin-1 receptor-associated kinase (IRAK) family between the human andmouse TLR pathways. Whereas TLR signaling inmousemacrophages depended primarily on IRAK4 and IRAK2, with little or no role for IRAK1, TLR signaling and proinflammatory cytokine production in human macrophages depended on IRAK1, with knockdown of IRAK4 or IRAK2 having less of an effect. Consistent with species-specific roles for these kinases, IRAK4 orthologs failed to rescue signaling in IRAK4-deficient macrophages from the other species, and only mouse macrophages required the kinase activity of IRAK4 to mediate TLR responses. The identification of a critical role for IRAK1 in TLR signaling in humans could potentially explain the association of IRAK1 with several autoimmune diseases. Furthermore, this study demonstrated how systematic screening can be used to identify important characteristics of innate immune responses across species, which could optimize therapeutic targeting to manipulate human TLR-dependent outputs.
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U2 - 10.1126/scisignal.aab2191
DO - 10.1126/scisignal.aab2191
M3 - Article
C2 - 26732763
AN - SCOPUS:84954504744
SN - 1945-0877
VL - 9
JO - Science signaling
JF - Science signaling
IS - 409
M1 - ra3
ER -