Important aspects of Toll-like receptors, ligands and their signaling pathways.
Due to the rapid increase of new information on the multiple roles of Toll-like receptors (TLRs), this paper reviews several main properties of TLRs and their ligands and signaling pathways. The investigation of pathogen infections in knockout mice suggests that specific TLRs play a key role in the activation of immune responses. Although the investigation of TLR biology is just beginning, a number of important findings are emerging. This review focuses on the following seven aspects of this emerging field: (a) a history of TLR and ligand studies; (b) the molecular basis of recognition by TLRs: TLR structures, pathogen-associated molecular pattern binding sites, TLR locations and functional responses; (c) cell types in TLR expression; (d) an overview of TLRs and their ligands: expression and ligands of cell-surface TLRs and of intracellular TLRs; (e) TLR-signaling pathways; (f) discussion: TLRs control of innate and adaptive systems; the trafficking of intracellular TLRs to endolysosomes; investigation of TLRs in regulating microRNA; investigation of crystal structure of TLRs with ligand binding; incidence of infectious diseases associated with single nucleotide polymorphisms (SNPs) in TLR genes; risk of cancer related to SNPs in TLR genes; TLR-ligand mediated anti-cancer effects; and TLR-ligand induced chronic inflammation and tumorigenesis; and (g) conclusions.
Chang
Z L
ZL
Institute of Biochemistry and Cell Biology, Shanghai Institute for Biological Science, Chinese Academy of Sciences, Shanghai 200031, China. chang_zong_liang@hotmail.com
D000818:Animals; D001665:Binding Sites; D006801:Humans; D007109:Immunity / Q000502:physiology; D007249:Inflammation / Q000473:pathology / Q000503:physiopathology; D008024:Ligands; D035683:MicroRNAs / Q000276:immunology; D008958:Models, Molecular; D009369:Neoplasms / Q000235:genetics / Q000276:immunology; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology*; D051193:Toll-Like Receptors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D059016:Tumor Microenvironment
D008024:Ligands; D035683:MicroRNAs; D020033:Protein Isoforms; D051193:Toll-Like Receptors