Molecular evolution of ancient TIR containing gene family in innate immunity

为了揭示一个库的Toll样受体（TLR）和TIR含有信号分子在一个基础的后口，我们分析了EST的有柄海百合，Metacrinus rotundas，其胚胎和幼虫的cDNA已测序的下一个基因测序。到目前为止，我们共鉴定出6个TLR，其中3个为蝇类TLR基因，3个为脊椎动物类TLR基因。在海百合的cDNA中还发现了MyD 88样基因和Sarm样基因，表明这些基因存在于基部后口中。我们在海百合的测序数据中发现了独特的TIR基因家族CARD-TIR和TPR-TIR，这在海胆的基因组中没有，但在文昌鱼的基因组中。这些数据表明，基底后口可以利用多基因的TLR和各种类型的TIR含有基因。而TLRs和信号分子的修饰可能发生在获得性免疫出现之后。

To unveil a repertoire of Toll-like receptors (TLRs) and TIR containing signaling molecules in a basal deuterostome, we analyzed EST of a stalked crinoid, Metacrinus rotundas, whose embryonic and larval cDNA have been sequenced by Next Gene Sequencing. So far, we identified 6 TLRs that consist of 3 genes of fly-type and 3 genes of vertebrate type TLRs. MyD88-like genes and Sarm-like genes were also identified in the cDNA of the sea lily, suggesting these genes exist in a basal deuterostome. We found unique TIR containing gene families, CARD-TIR and TPR-TIR, in the sequencing data of the sea lily, which have not been in the genome of the sea urchin, but in that of amphioxus. These data suggest a basal deuterostome could utilize multigenes of TLRs and various types of TIR containing genes. And the refinement of TLRs and signaling molecules could happen after the appearance of acquired immunity.