There is 35% homology between the amino acid residue of the Ang and RNase and their similar spatial structure can both combine with RI as ligand.

• 血管生成因子的氨基酸残基组成与核糖核酸酶具有35%25的同源性,它们有着极其相似的空间结构都可以作为配体与RI结合。