Novel Splice Variants of Bovine Interleukin-1 Receptor-Associated Kinase 2 (IRAK2)

Interleukin-1 receptor-associated kinases (IRAKs) are important signaling elements of the toll-like receptors family, which play a role in innate immune responses by coordinating host defense mechanisms. Presently different isoforms of human and murine IRAK2 molecules are cloned, but there is no report on the sequences and structure of bovine IRAK2 gene. In this study, we cloned the bovine IRAK2 gene by RT-PCR and RACE and discovered that there exist two alternative splicing of bovine IRAK2 genes, IRAK2a and IRAK2b (GenBank accession no. EU528620 and EU528621). IRAK2a gene is 2 148 bp coding 622 aa, which contains a death domain (aa 14-94) and a kinase domain (aa 205-440), but IRAK2b lacks 147 bp of exon 3 corresponding to IRAK2a, and codes 386 aa which contains only partly kinase domain.