Repurposed transcriptomes facilitate discovery of innate immunity Toll-Like Receptor (TRLs) genes across Lophotrochozoa
Identifiers: SRA: SRP048758
The growing volume of genomic data from across life represents opportunities for deriving valuable biological information from data that was initially collected for another purpose. Here, we use transcriptomes collected for phylogenomic studies to search for Toll-Like Receptor (TRL) genes in poorly sampled lophotrochozoan clades (Annelida, Mollusca, Brachiopoda, Phoronida, and Entoprocta) and one ecdysozoan clade (Priapula). TRL genes are involved in innate immunity across animals by recognizing potential microbial infection. They have an extracellular Leucine-Rich Repeat (LRR) domain connected to transmembrane and intracellular Toll/Interleukin-1 Receptor (TIR) domains. As such, these genes are important in initiating a signaling pathway to initiate defense. We found at least one TRL ortholog in all taxa examined suggesting all these taxa may have innate immune systems similar to those observed in vertebrates and arthropods. Comparison to the SMART database to confirmed the presence of both the LRR and the TIR protein motifs characteristic of TRL genes. Because we looked at only one transcriptome per species, the discovery of TRL genes was limited for most taxa. However, several where found in phoronids which vary in the placement and number of LRR domains. Additionally several of the LRR containing genes were discovered, some likely involved in innate immunity.