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The Drosophila peptidoglycan-recognition protein LF interacts with peptidoglycan-recognition protein LC to downregulate the Imd pathway.

ABSTRACT: The peptidoglycan (PGN)-recognition protein LF (PGRP-LF) is a specific negative regulator of the immune deficiency (Imd) pathway in Drosophila. We determine the crystal structure of the two PGRP domains constituting the ectodomain of PGRP-LF at 1.72 and 1.94 Å resolution. The structures show that the LFz and LFw domains do not have a PGN-docking groove that is found in other PGRP domains, and they cannot directly interact with PGN, as confirmed by biochemical-binding assays. By using surface plasmon resonance analysis, we show that the PGRP-LF ectodomain interacts with the PGRP-LCx ectodomain in the absence and presence of tracheal cytotoxin. Our results suggest a mechanism for downregulation of the Imd pathway on the basis of the competition between PRGP-LCa and PGRP-LF to bind to PGRP-LCx.

SUBMITTER: Basbous N

PROVIDER: S-EPMC3077246 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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The Drosophila peptidoglycan-recognition protein LF interacts with peptidoglycan-recognition protein LC to downregulate the Imd pathway.

Basbous Nada N Coste Franck F Leone Philippe P Vincentelli Renaud R Royet Julien J Kellenberger Christine C Roussel Alain A

EMBO reports 20110304 4

The peptidoglycan (PGN)-recognition protein LF (PGRP-LF) is a specific negative regulator of the immune deficiency (Imd) pathway in Drosophila. We determine the crystal structure of the two PGRP domains constituting the ectodomain of PGRP-LF at 1.72 and 1.94 Å resolution. The structures show that the LFz and LFw domains do not have a PGN-docking groove that is found in other PGRP domains, and they cannot directly interact with PGN, as confirmed by biochemical-binding assays. By using surface pla ...[more]

PMID: 21372849

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