TIRAP in the Mechanism of Inflammation

• Published in: Frontiers in immunology Vol. 12; p. 697588
• Main Authors: Rajpoot, Sajjan, Wary, Kishore K, Ibbott, Rachel, Liu, Dongfang, Saqib, Uzma, Thurston, Teresa L M, Baig, Mirza S
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 08.07.2021
• Subjects: Agammaglobulinaemia Tyrosine Kinase - immunology; Agammaglobulinaemia Tyrosine Kinase - metabolism; Animals; Carrier Proteins - immunology; Carrier Proteins - metabolism; Class Ia Phosphatidylinositol 3-Kinase - immunology; Class Ia Phosphatidylinositol 3-Kinase - metabolism; Humans; Immunity, Innate; Immunology; inflammation; Inflammation - immunology; Inflammation - metabolism; inflammatory disease; Membrane Glycoproteins - immunology; Membrane Glycoproteins - metabolism; Models, Biological; Protein Interaction Maps; Protein Kinase C-delta - immunology; Protein Kinase C-delta - metabolism; protein-protein interaction (PPI); Receptor for Advanced Glycation End Products - immunology; Receptor for Advanced Glycation End Products - metabolism; Receptors, Interleukin-1 - immunology; Receptors, Interleukin-1 - metabolism; Signal Transduction - immunology; TIRAP (TIR domain-containing adaptor protein); TLR signaling; TLR signaling; inflammatory disease; protein-protein interaction (PPI); inflammation; TIRAP (TIR domain-containing adaptor protein)
• ISSN: 1664-3224; 1664-3224
• DOI: 10.3389/fimmu.2021.697588

The Toll-interleukin-1 Receptor (TIR) domain-containing adaptor protein (TIRAP) represents a key intracellular signalling molecule regulating diverse immune responses. Its capacity to function as an adaptor molecule has been widely investigated in relation to Toll-like Receptor (TLR)-mediated innate immune signalling. Since the discovery of TIRAP in 2001, initial studies were mainly focused on its role as an adaptor protein that couples Myeloid differentiation factor 88 (MyD88) with TLRs, to activate MyD88-dependent TLRs signalling. Subsequent studies delineated TIRAP's role as a transducer of signalling events through its interaction with non-TLR signalling mediators. Indeed, the ability of TIRAP to interact with an array of intracellular signalling mediators suggests its central role in various immune responses. Therefore, continued studies that elucidate the molecular basis of various TIRAP-protein interactions and how they affect the signalling magnitude, should provide key information on the inflammatory disease mechanisms. This review summarizes the TIRAP recruitment to activated receptors and discusses the mechanism of interactions in relation to the signalling that precede acute and chronic inflammatory diseases. Furthermore, we highlighted the significance of TIRAP-TIR domain containing binding sites for several intracellular inflammatory signalling molecules. Collectively, we discuss the importance of the TIR domain in TIRAP as a key interface involved in protein interactions which could hence serve as a therapeutic target to dampen the extent of acute and chronic inflammatory conditions.