Amphibians have immunoglobulins similar to ancestral IgD and IgA from Amniotes

作者：Estevez Olivia; Garet Elina; Olivieri David^*; Gambon Deza Francisco

来源：Molecular Immunology, 2016, 69: 52-61.

DOI：10.1016/j.molimm.2015.11.005

• Amphibian immunoglobulins
• Evolution of immunoglobulins

We studied the immunoglobulin genes from either the genomes or RNAs of amphibians. In particular, we obtained data from one frog genome (Nanorana parkeri) and three transcriptomes of the Caudata order (Andrias davidianus, Notophthalmus viridescens and Cynops pyrrhogaster). Apart from the immunoglobulins IgM and IgY previously described, we identified several IgD related immunoglobulins. The species N. parkeri, N. viridescens and C. pyrrhogaster have two IgD genes, while Andrias davidianus has three such genes. The three Caudata species have long IgD immunoglobulins similar to IgD of reptiles, and could be an ancient relic from the common ancestor of IgD of all mammals and reptiles. We also found two IgA isotypes. The results suggest that one of the IgA may be the ancestor of IgA in crocodiles and birds, while the other could be the ancestor IgA found in mammals. These results provide information that could help understand the evolution of immunoglobulins in terrestrial vertebrates.

• 出版日期2016-1