, Volume 20, Issue 2, pp 250–261 | Cite as

Structure and function of Toll/interleukin-1 receptor/resistance protein (TIR) domains

The Domains of Apoptosis and Inflammation


The Toll/interleukin-1 receptor/resistance protein (TIR) domain is a protein–protein interaction domain consisting of 125–200 residues, widely distributed in animals, plants and bacteria but absent from fungi, archea and viruses. In plants and animals, these domains are found in proteins with functions in innate immune pathways, while in bacteria, some TIR domain-containing proteins interfere with the innate immune pathways in the host. TIR domains function as protein scaffolds, mostly involving self-association and homotypic interactions with other TIR domains. In the last 15 years, the three-dimensional structures of TIR domains from several mammalian, plant and bacterial proteins have been reported. These structures, jointly with functional data including the identification of interacting proteins, have started to provide insight into the molecular basis of the assembly of animal and plant immune signaling complexes, and for host immunosuppression by bacterial pathogens. This review focuses on the current knowledge of the structures of the TIR domains and how the structure relates to function.


Innate immunity Nod-like receptor (NLR) Plant disease resistance protein Toll/interleukin-1 receptor/resistance protein (TIR) domain Toll-like receptor 


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.School of Chemistry and Molecular Biosciences, Institute for Molecular Bioscience and Australian Infectious Diseases Research CentreUniversity of QueenslandBrisbaneAustralia

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