A peptidoglycan recognition protein in innate immunity conserved from insects to humans.
Innate nonself recognition must rely on common structures of invading microbes. In a differential display screen for up-regulated immune genes in the moth Trichoplusia ni we have found mechanisms for recognition of bacterial cell wall fragments. One bacteria-induced gene encodes a protein that, after expression in the baculovirus system, was shown to be a peptidoglycan recognition protein (PGRP). It binds strongly to Gram-positive bacteria. We have also cloned the corresponding cDNA from mouse and human and shown this gene to be expressed in a variety of organs, notably organs of the immune system-i.e., bone marrow and spleen. In addition, purified recombinant murine PGRP was shown to possess peptidoglycan affinity. From our results and the sequence homology, we conclude that PGRP is a ubiquitous protein involved in innate immunity, conserved from insects to humans.
Kang
D
D
Department of Microbiology, Stockholm University, S-106 91 Stockholm, Sweden.
Liu
G
G
Lundström
A
A
Gelius
E
E
Steiner
H
H
D000595:Amino Acid Sequence; D000818:Animals; D001419:Bacteria / Q000276:immunology; D016367:Baculoviridae / Q000235:genetics; D001483:Base Sequence; D017124:Conserved Sequence; D006801:Humans; D007109:Immunity / Q000235:genetics*; D019476:Insect Proteins / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D009036:Moths / Q000235:genetics* / Q000276:immunology*; D010457:Peptidoglycan / Q000276:immunology* / Q000378:metabolism; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D011506:Proteins / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
D019476:Insect Proteins; D010457:Peptidoglycan; D011506:Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins