title: The surprisingly complex immune gene repertoire of a simple sponge, exemplified by the NLR genes: a capacity for specificity?
abstract: Most bacteria are not pathogenic to animals, and may instead serve beneficial functions. The requisite need for animals to differentiate between microbial friend and foe is likely borne from a deep evolutionary imperative to recognise self from non-self, a service ably provided by the innate immune system. Recent findings from an ancient lineage of simple animals - marine sponges - have revealed an unexpectedly large and diverse suite of genes belonging to one family of pattern recognition receptors, namely the NLR genes. Because NLRs can recognise a broad spectrum of microbial ligands, they may play a critical role in mediating the animal-bacterial crosstalk needed for sophisticated discrimination between microbes of various relationships. The building blocks for an advanced NLR-based immune specificity encoded in the genome of the coral reef sponge Amphimedon queenslandica may provide a specialisation and diversity of responses that equals, or even exceeds, that of vertebrate NLRs.
authors: School of Biological Sciences, The University of Queensland, Brisbane, Qld., Australia. Electronic address: s.degnan@uq.edu.au.
authors: Sandie M
authors: SM
authors: Degnan
mesh_terms: D000818:Animals; D007113:Immunity, Innate; D007156:Immunologic Memory; D011161:Porifera / Q000235:genetics* / Q000276:immunology* / Q000382:microbiology; D051192:Receptors, Pattern Recognition / Q000276:immunology
chemical_list: D051192:Receptors, Pattern Recognition
keywords: Amphimedon; Leucine rich repeats; NACHT domain; Pattern recognition receptors; Porifera; Symbiosis