Pattern Recognition Receptors in Drosophila
The foundation of the innate immune system is the recognition of infectious non-self. Janeway (1,2) has proposed that this recognition is mediated by the binding of host pattern recognition proteins to pathogen-associated molecular patterns (PAMPs). PAMPs were originally defined as structures found on the surfaces of microorganisms but not present on normal host cells. More recently, this definition has been broadened to include intracellular components of microorganisms, such as CpG DNA (3). There are several different classes of pattern recognition proteins including secreted, membrane-bound, and integral membrane proteins, and some pattern recognition molecules can exist in more than one of these forms. Recognition of PAMPs by pattern recognition proteins has several consequences, including the activation of induced cellular and humoral immune responses, such as the induction of antimicrobial genes in Drosophila, and the activation of T- cells in mammals. Pattern recognition proteins also participate in the effector mechanisms of the immune system, such as the complement (mammals) and prophenoloxidase (insect) cascades, as well as phagocytosis of microorganisms.
KeywordsScavenger Receptor Pattern Recognition Receptor Horseshoe Crab Recognition Protein Macrophage Scavenger Receptor
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- 4.Volanakis JE. Overview of the complement system. In: Volanakis JE, Frank MM (eds.). The Human Complement System in Health and Disease. New York: Marcel Dekker, 1998, pp:9–32.Google Scholar
- 11.Kim YS, Ryu JH, Han SJ, et al. Gram-negative bacteria-binding protein, a pattern recognition receptor for lipopolysaccharide and beta-1,3-glucan that mediates the signaling for the induction of innate immune genes in Drosophila melanogaster cells. J Biol Chem 2000;275:32721–32727.PubMedCrossRefGoogle Scholar
- 30.Ramet M, Manfruelli P, Pearson A, Mathey-Prevot B, Ezekowitz RA. Functional genomic analysis of phagocytosis and identification of a Drosophila receptor for E. coli. Nature 2002;416:644 648.Google Scholar