The DYKDDDDK peptide has been used extensively as a general epitope tag in expression vectors. This peptide can be expressed and detected with the protein of interest as an amino-terminal or carboxy-terminal fusion.

Epitope tags are useful for the labeling and detection of proteins using immunoblotting,immunoprecipitation, and immunostaining techniques. Because of their small size, they are unlikely to affect the tagged protein’s biochemical properties.

Human influenza hemagglutinin (HA) is a surface glycoprotein required for the infectivity of the human virus. The HA tag derived from the HA molecule corresponding to amino acids 98-106 has been extensively used as a general epitope tag in expression vectors.

The V5 epitope tag is derived from a small epitope(Pk) present on the P and V proteins of theparamyxovirus of simian virus 5 (SV5). The V5 tag isusually used with all 14 amino acids (GKPIPNPLLGLDST), and useful for western blotting,immunofluorescence and immunoprecipitation experiments.

GST (Glutathione S-Transferase) is a 26kDa protein，encoded by the parasitic helminth Schistosoma japonicum and widely used in the pGEX family of GSTplasmid expression vectors as a fusion protein with foreign proteins.This antibody can recognize both