Encyclopedia of Signaling Molecules

2018 Edition
| Editors: Sangdun Choi

Toll-Like Receptor 9

  • Felipe Francisco Tuon
Reference work entry
DOI: https://doi.org/10.1007/978-3-319-67199-4_14

Synonyms

 TLR9

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...

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References

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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Division of Infectious and Parasitic DiseasesHospital Universitario Evangelico de CuritibaCuritibaBrazil