Biology of Toll receptors: lessons from insects and mammals.
Toll receptors are type I transmembrane proteins that play important roles in development and immunity in animals. Comparison of the genomes of mouse and human on one side and of the fruitfly Drosophila and the mosquito Anopheles (two dipteran insects) on the other, revealed that the four species possess a similar number of Toll receptors (approximately 10). However, phylogenetic analyses indicate that the families of Toll receptors expanded independently in insects and mammals. We review recent results on these receptors, which point to differences in the activation and signaling between Tolls in insects and Toll-like receptors (TLRs) in mammals. Whereas mammalian TLRs appear to be solely dedicated to host-defense, insect Tolls may be predominantly linked to other functions, probably developmental.
Imler
Jean-Luc
JL
Institut de Biologie Moléculaire et Cellulaire, CNRS, 15 rue René Descartes, 67000 Strasbourg, France. JL.Imler@ibmc.u-strasbg.fr
Zheng
Liangbiao
L
D000818:Animals; D000852:Anopheles; D004330:Drosophila; D029721:Drosophila Proteins; D006801:Humans; D008562:Membrane Glycoproteins / Q000145:classification / Q000502:physiology*; D051379:Mice; D010802:Phylogeny; D018521:Plant Physiological Phenomena; D011956:Receptors, Cell Surface / Q000145:classification / Q000502:physiology*; D015398:Signal Transduction; D051198:Toll-Like Receptor 5; D051193:Toll-Like Receptors
D029721:Drosophila Proteins; D008562:Membrane Glycoproteins; D011956:Receptors, Cell Surface; D051198:Toll-Like Receptor 5; D051193:Toll-Like Receptors; C495341:tehao protein, Drosophila