The cadherinrepeated domains of Bt- R3 protein share high homology with the cadherin domains from African clawed frog (Xenopus laevis) and E-cadherin (epithelial) from mouse (Mus musculus).

• Bt-R3受体蛋白的钙粘蛋白结构域分别与非洲爪蟾(Xenopus laevis)的钙粘蛋白胞外结构域和小鼠(Mus musculus)的上皮钙粘蛋白胞外结构域有很高的同源性。