title: 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.
authors.affiliation: Department of Genetics, Microbiology, and Toxicology, University of Stockholm, S-106 91 Stockholm, Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Mellroth
authors.forename: Jenny
authors.initials: J
authors.lastname: Karlsson
authors.forename: Janet
authors.initials: J
authors.lastname: Håkansson
authors.forename: Niklas
authors.initials: N
authors.lastname: Schultz
authors.forename: William E
authors.initials: WE
authors.lastname: Goldman
authors.forename: Håkan
authors.initials: H
authors.lastname: Steiner
mesh_terms: D000818:Animals; D001419:Bacteria / Q000276:immunology / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D002460:Cell Line; D002473:Cell Wall / Q000378:metabolism; D019281:Dimerization; D004330:Drosophila / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D005822:Genetic Vectors / Q000235:genetics; D007150:Immunohistochemistry; D008024:Ligands; D008954:Models, Biological; D009943:Organophosphorus Compounds; D010457:Peptidoglycan / Q000378:metabolism*; D020539:Sequence Analysis, Protein; D015398:Signal Transduction / Q000276:immunology*
chemical_list: C043517:2-(4-isothiocyanatophenoxy)-1,3,2-dioxaphosphinene 2-oxide; D002352:Carrier Proteins; D008024:Ligands; D009943:Organophosphorus Compounds; D010457:Peptidoglycan; C118897:peptidoglycan recognition protein