Synonyms
Historical Background
Toll receptors are transmembrane proteins that are evolutionarily conserved. These receptors were first recognized in Drosophila, as an essential molecule for embryogenic patterning (Anderson 2000).
Activation of these receptors in Drosophila initiates an intracellular kinase cascade that produces a translocation of transcription factors from cytoplasm to nucleus. These factors activate a variety of inflammatory mediators and cytokines, initiating an immune response (Imler and Hoffmann 2000).
Considering these facts, some researchers began a search for toll-related proteins in humans. In 1997, they identified the first human homologue, initially termed “human toll” and subsequently termed TLR4 (Medzhitov et al. 1997). After this, more toll-like receptors were discovered, as TLR1, TLR2, TLR3, TLR5, and TLR6.
In 2000, Du et al. examined the human genomic sequence database in an effort to identify novel TLRs (Du et al. 2000). He found more three TLRs,...
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Anderson KV. Toll signaling pathways in the innate immune response. Curr Opin Immunol. 2000;12:13–9.
Baeuerle PA, Baltimore D. NF-kB: ten years after. Cell. 1996;87:13–20.
Barton GM, Kagan JC, Medzhitov R. Intracellular localization of Toll-like receptor 9 prevents recognition of self DNA but facilitates access to viral DNA. Nat Immunol. 2006;7:49–56.
Bauer S, Kirschning CJ, Hacker H, et al. Human TLR9 confers responsiveness to bacterial DNA via species-specific CpG motif recognition. Proc Natl Acad Sci USA. 2001;98:9237–42.
Chuang TH, Ulevitch RJ. Cloning and characterization of a sub-family of human toll-like receptors: hTLR7, hTLR8 and hTLR9. Eur Cytokine Netw. 2000;11:372–8.
Du X, Poltorak A, Wei Y, Beutler B. Three novel mammalian toll-like receptors: gene structure, expression, and evolution. Eur Cytokine Netw. 2000;11:362–71.
Gangloff M, Gay NJ. Baseless assumptions: activation of TLR9 by DNA. Immunity. 2008;28:293–4.
Hacker H, Mischak H, Hacker G, et al. Cell type-specific activation of mitogen-activated protein kinases by CpG-DNA controls interleukin-12 release from antigen-presenting cells. EMBO J. 1999;18:6973–82.
Hacker H, Vabulas RM, Takeuchi O, Hoshino K, Akira S, Wagner H. Immune cell activation by bacterial CpG-DNA through myeloid differentiation marker 88 and tumor necrosis factor receptorassociated factor (TRAF)6. J Exp Med. 2000;192:595–600.
Hemmi H, Takeuchi O, Kawai T, Kaisho T, Sato S, Sanjo HA. Toll-like receptor recognizes bacterial DNA. Nature. 2000;408:740–5.
Hickey MJ, Williams SA, Roth GJ. Human platelet glycoprotein IX: an adhesive prototype of leucine-rich glycoproteins with flank-center-flank structures. Proc Natl Acad Sci USA. 1989;86:6773–7.
Imler JL, Hoffmann JA. Signaling mechanisms in the antimicrobial host defense of Drosophila. Curr Opin Microbiol. 2000;3:16–22.
Krieg AM. Antiinfective applications of toll-like receptor 9 agonists. Proc Am Thorac Soc. 2007;4:289–94.
Krieg AM. Toll-like receptor 9 (TLR9) agonists in the treatment of cancer. Oncogene. 2008;27:161–7.
Krieg AM, Vollmer J. Toll-like receptors 7, 8, and 9: linking innate immunity to autoimmunity. Immunol Rev. 2007;220:251–69.
Medzhitov R, Preston-Hurlburt P, Janeway Jr CAA. human homologue of the Drosophila Toll protein signals activation of adaptive immunity. Nature. 1997;388:394–7.
Schnare M, Holt AC, Takeda K, Akira S, Medzhitov R. Recognition of CpG DNA is mediated by signaling pathways dependent on the adaptor protein MyD88. Curr Biol. 2000;10:1139–42.
Sun S, Rao NL, Venable J, Thurmond R, Karlsson L. TLR7/9 antagonists as therapeutics for immune-mediated inflammatory disorders. Inflamm Allergy Drug Targets. 2007;6:223–35.
Tuon FF, Fernandes ER, Duarte MI, Amato VS. The expression of TLR2, TLR4 and TLR9 in the epidermis of patients with cutaneous leishmaniasis. J Dermatol Sci. 2010a;59:55–7.
Tuon FF, Fernandes ER, Pagliari C, Duarte MI, Amato VS. The expression of TLR9 in human cutaneous leishmaniasis is associated with granuloma. Parasite Immunol. 2010b;32:769–72.
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Tuon, F.F. (2018). Toll-Like Receptor 9. In: Choi, S. (eds) Encyclopedia of Signaling Molecules. Springer, Cham. https://doi.org/10.1007/978-3-319-67199-4_14
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DOI: https://doi.org/10.1007/978-3-319-67199-4_14
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