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Screening Bioactive Nanoparticles in Phagocytic Immune Cells for Inhibitors of Toll-like Receptor Signaling
Published on: July 26, 2017
Toll-like receptors--taking an evolutionary approach.
François Leulier1, Bruno Lemaitre
1CNRS, Centre de Génétique Moléculaire, UPR2167, Gif-sur-Yvette, F-91198, France. francois.leulier@cgm.cnrs-gif.fr
Nature Reviews. Genetics
|January 30, 2008
Summary
Toll receptors, initially found in fruit flies, are crucial for immunity in animals. This review explores their evolutionary history and diverse roles across species, suggesting independent adaptations for immune functions.
Area of Science:
- Immunology
- Evolutionary Biology
- Molecular Biology
Background:
- Toll receptors were first identified in Drosophila melanogaster, playing a role in embryonic development.
- Toll and Toll-like receptors (TLRs) are now recognized as critical regulators of immune responses in both insects and mammals.
- Extensive research has generated significant genomic and functional data on TLRs across various organisms.
Purpose of the Study:
- To review the distribution and functions of Toll-like receptors (TLRs) throughout the animal kingdom.
- To provide an evolutionary perspective on the origin and diversification of TLRs.
- To explore hypotheses regarding the independent co-option of different TLRs for analogous immune functions during animal evolution.
Main Methods:
- Comprehensive literature review of existing genomic and functional data on TLRs.
- Comparative analysis of TLR distribution and characteristics across diverse animal taxa.
- Evolutionary analysis to trace the origin and diversification of TLR genes.
Main Results:
- TLRs are widely distributed across the animal kingdom, indicating ancient origins.
- Diverse functions of TLRs have been identified, extending beyond initial roles in development to encompass innate immunity.
- Evidence suggests that distinct TLRs may have evolved independently in different animal lineages to perform similar immune functions.
Conclusions:
- Toll-like receptors represent a conserved system with ancient evolutionary roots, predating the emergence of complex immune systems.
- The functional repertoire of TLRs has expanded through evolutionary processes, with independent recruitment events contributing to their diverse roles in immunity.
- Understanding the evolutionary trajectory of TLRs provides insights into the fundamental mechanisms of innate immunity across the animal kingdom.
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