RNA interference and receptors

@article{michel_drosophila_2001,

title = {Drosophila Toll is activated by Gram-positive bacteria through a circulating peptidoglycan recognition protein},

author = {T Michel and Jean-Marc Reichhart and Jules A Hoffmann and Julien Royet},

doi = {10.1038/414756a},

issn = {0028-0836},

year  = {2001},

date = {2001-12-01},

journal = {Nature},

volume = {414},

number = {6865},

pages = {756--759},

abstract = {Microbial infection activates two distinct intracellular signalling cascades in the immune-responsive fat body of Drosophila. Gram-positive bacteria and fungi predominantly induce the Toll signalling pathway, whereas Gram-negative bacteria activate the Imd pathway. Loss-of-function mutants in either pathway reduce the resistance to corresponding infections. Genetic screens have identified a range of genes involved in these intracellular signalling cascades, but how they are activated by microbial infection is largely unknown. Activation of the transmembrane receptor Toll requires a proteolytically cleaved form of an extracellular cytokine-like polypeptide, Spätzle, suggesting that Toll does not itself function as a bona fide recognition receptor of microbial patterns. This is in apparent contrast with the mammalian Toll-like receptors and raises the question of which host molecules actually recognize microbial patterns to activate Toll through Spätzle. Here we present a mutation that blocks Toll activation by Gram-positive bacteria and significantly decreases resistance to this type of infection. The mutation semmelweis (seml) inactivates the gene encoding a peptidoglycan recognition protein (PGRP-SA). Interestingly, seml does not affect Toll activation by fungal infection, indicating the existence of a distinct recognition system for fungi to activate the Toll pathway.},

keywords = {Amino Acid, Animals, Anti-Bacterial Agents, Anti-Infective Agents, Bacillus thuringiensis, Carrier Proteins, Cell Surface, Chromosome Mapping, Enterococcus faecalis, Fungi, Genes, Gram-Positive Bacteria, Hemolymph, hoffmann, Humans, Insect, Insect Proteins, M3i, Membrane Glycoproteins, Micrococcus luteus, Mutation, Receptors, reichhart, Sequence Homology, Toll-Like Receptors},

pubstate = {published},

tppubtype = {article}

}

@article{hoffmann_first_1977,

title = {First results of the antibacterial defense reactions of Locusta migratoria larva and imago},

author = {Danièle Hoffmann and M Brehelin and Jules A Hoffmann},

issn = {0003-4150},

year  = {1977},

date = {1977-02-01},

journal = {Ann Parasitol Hum Comp},

volume = {52},

number = {1},

pages = {87--88},

keywords = {Animals, Bacillus thuringiensis, bacteria, Cellular, Grasshoppers, Hematopoietic System, Hemocytes, Hemolymph, hoffmann, Immunity, Larva, M3i, Muramidase},

pubstate = {published},

tppubtype = {article}

}