Nav1.7 inhibitor and transformation method

The present invention provides a Nav1.7 inhibitor and a transformation method, and the inhibitor belongs to fusion protein, and comprises two parts of a protein mutant using SEQ ID NO: 2 as a template and a polypeptide capable of blocking Nav1.7 current. The protein mutant using SEQ ID NO: 2 as the template is a mutant formed by amino acid insertion, deletion and substitution of 14th-31th sites of the sequence SEQ ID NO: 2. The present invention also provides the transformation method which is as follows: the suppressing polypeptide capable of blocking the Nav1.7 current and the protein mutant using SEQ ID NO: 2 as the template are connected, and fused with MBP tag protein in an expression vector, and a fusion protein capable of blocking the Nav1.7 current can be solubly expressed in E. coli cells. The beneficial effects are that: the fusion protein can be solubly expressed in the E. coli cells, a purified product can block the Nav1.7 current on dorsal root ganglion (DRG) cell membrane, the effect is similar to that of the original polypeptide, the combination time is longer, the fusion protein is more difficult to elute, and shows a significant analgesic effect in in-vivo experiments in rats.