Rédigé le 1 janvier 1998 à 12:00 par , publié dans Non classé.

Elena A. Levashina, S. Ohresser, Bruno Lemaitre, Jean-Luc Imler: Two distinct pathways can control expression of the gene encoding the Drosophila antimicrobial peptide metchnikowin. Dans: Journal of Molecular Biology, 278 (3), p. 515–527, 1998, ISSN: 0022-2836.

Résumé

Metchnikowin is a recently discovered proline-rich peptide from Drosophila with antibacterial and antifungal properties. Like most other antimicrobial peptides from insects, its expression is immune-inducible. Here we present evidence that induction of metchnikowin gene expression can be mediated either by the TOLL pathway or by the imd gene product. We show that the gene remains inducible in Toll-deficient mutants, in which the antifungal response is blocked, as well as in imd mutants, which fail to mount an antibacterial response. However, in Toll-deficient;imd double mutants, metchnikowin gene expression can no longer be detected after immune challenge. Our results suggest that expression of this peptide with dual activity can be triggered by signals generated by either bacterial or fungal infection. Cloning of the metchnikowin gene revealed the presence in the 5' flanking region of several putative cis-regulatory motifs characterized in the promoters of insect immune genes: namely, Rel sites, GATA motifs, interferon consensus response elements and NF-IL6 response elements. Establishment of transgenic fly lines in which the GFP reporter gene was placed under the control of 1.5 kb of metchnikowin gene upstream sequences indicates that this fragment is able to confer full immune inducibility and tissue specificity of expression on the transgene.

BibTeX (Download)

@article{levashina_two_1998,
title = {Two distinct pathways can control expression of the gene encoding the Drosophila antimicrobial peptide metchnikowin},
author = { Elena A. Levashina and S. Ohresser and Bruno Lemaitre and Jean-Luc Imler},
doi = {10.1006/jmbi.1998.1705},
issn = {0022-2836},
year  = {1998},
date = {1998-01-01},
journal = {Journal of Molecular Biology},
volume = {278},
number = {3},
pages = {515--527},
abstract = {Metchnikowin is a recently discovered proline-rich peptide from Drosophila with antibacterial and antifungal properties. Like most other antimicrobial peptides from insects, its expression is immune-inducible. Here we present evidence that induction of metchnikowin gene expression can be mediated either by the TOLL pathway or by the imd gene product. We show that the gene remains inducible in Toll-deficient mutants, in which the antifungal response is blocked, as well as in imd mutants, which fail to mount an antibacterial response. However, in Toll-deficient;imd double mutants, metchnikowin gene expression can no longer be detected after immune challenge. Our results suggest that expression of this peptide with dual activity can be triggered by signals generated by either bacterial or fungal infection. Cloning of the metchnikowin gene revealed the presence in the 5' flanking region of several putative cis-regulatory motifs characterized in the promoters of insect immune genes: namely, Rel sites, GATA motifs, interferon consensus response elements and NF-IL6 response elements. Establishment of transgenic fly lines in which the GFP reporter gene was placed under the control of 1.5 kb of metchnikowin gene upstream sequences indicates that this fragment is able to confer full immune inducibility and tissue specificity of expression on the transgene.},
keywords = {Animals, Anti-Infective Agents, Antimicrobial Cationic Peptides, Base Sequence, Cloning, Gene Expression Regulation, Genes, Genetic, Genetically Modified, Glycopeptides, Insect, Insect Proteins, Larva, Molecular, Mutation, Peptides, Promoter Regions, Recombinant Fusion Proteins, Reporter, Restriction Mapping, Transcription},
pubstate = {published},
tppubtype = {article}
}