title: TIR-domain-containing protein repertoire of nine anthozoan species reveals coral-specific expansions and uncharacterized proteins.
abstract: The intracellular toll/interleukin-1 receptor (TIR) domain plays an important role in vertebrate immunity, but the evolution and function of invertebrate TIR-domain-containing proteins is not fully understood. This study characterized and compared the TIR-domain-containing protein repertoire of nine cnidarians in class Anthozoa. A diverse set of proteins, including MyD88 (myeloid differentiation primary response protein 88), toll-like receptor (TLR)-like, interleukin-1 receptor (IL-1R)-like, and TIR-only proteins are present in the species surveyed. Increased numbers of TIR-only proteins were observed in corals compared to anemones, especially in the Acroporid and Pocilloporid coral families. This expansion could be linked to diversity of the microbial community on or in hosts and managing both positive and negative associations. Phylogenetic analysis indicates there are two groups of proteins with IL-1R-like domain architecture in anthozoans that potentially evolved independently of the vertebrate family. Bacterial-like TIR_2 domain proteins are also present, including one sequence with novel domain architecture. Overall this work promotes a better understanding of the anthozoan immune repertoire, which is important in the context learning about ancestral immune pathways and host-microbe interactions.
authors.affiliation: Oregon State University, Department of Integrative Biology, 3029 Cordley Hall, Corvallis, OR 97331, United States. Electronic address: poolea@science.oregonstate.edu.
authors.forename: Angela Z
authors.initials: AZ
authors.lastname: Poole
authors.affiliation: Oregon State University, Department of Integrative Biology, 3029 Cordley Hall, Corvallis, OR 97331, United States. Electronic address: weisv@science.oregonstate.edu.
authors.forename: Virginia M
authors.initials: VM
authors.lastname: Weis
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000235:genetics*; D019143:Evolution, Molecular; D053594:Myeloid Differentiation Factor 88 / Q000235:genetics; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D017472:Receptors, Interleukin-1 / Q000235:genetics; D051193:Toll-Like Receptors / Q000235:genetics
chemical_list: D053594:Myeloid Differentiation Factor 88; D017472:Receptors, Interleukin-1; D051193:Toll-Like Receptors
keywords: Anthozoa; IL-1R; TIR domain; TLR