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Ligand-induced dimerization of Drosophila peptidoglycan recognition proteins in vitro.

ABSTRACT: Drosophila knockout mutants have placed peptidoglycan recognition proteins (PGRPs) in the two major pathways controlling immune gene expression. We now examine PGRP affinities for peptidoglycan. PGRP-SA and PGRP-LCx are bona fide pattern recognition receptors, and PGRP-SA, the peptidoglycan receptor of the Toll/Dif pathway, has selective affinity for different peptidoglycans. PGRP-LCx, the default peptidoglycan receptor of the Imd/Relish pathway, has strong affinity for all polymeric peptidoglycans tested and for monomeric peptidoglycan. PGRP-LCa does not have affinity for polymeric or monomeric peptidoglycan. Instead, PGRP-LCa can form heterodimers with LCx when the latter is bound to monomeric peptidoglycan. Hence, PGRP-LCa can be said to function as an adaptor, thus adding a new function to a member of the PGRP family.

SUBMITTER: Mellroth P

PROVIDER: S-EPMC1088352 | biostudies-literature | 2005 May

REPOSITORIES: biostudies-literature

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Ligand-induced dimerization of Drosophila peptidoglycan recognition proteins in vitro.

Mellroth Peter P Karlsson Jenny J Håkansson Janet J Schultz Niklas N Goldman William E WE Steiner Håkan H

Proceedings of the National Academy of Sciences of the United States of America 20050420 18

Drosophila knockout mutants have placed peptidoglycan recognition proteins (PGRPs) in the two major pathways controlling immune gene expression. We now examine PGRP affinities for peptidoglycan. PGRP-SA and PGRP-LCx are bona fide pattern recognition receptors, and PGRP-SA, the peptidoglycan receptor of the Toll/Dif pathway, has selective affinity for different peptidoglycans. PGRP-LCx, the default peptidoglycan receptor of the Imd/Relish pathway, has strong affinity for all polymeric peptidoglyc ...[more]

PMID: 15843462

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