Epitope tags have application in the labeling, isolation and detection of proteins using immunoblotting, Immunoprecipitation and immunostaining techniques. By affinity chromatography, epitope tags can be used to separate recombinant, overexpressed protein from wild-type protein expressed by the host organism. The protein’s biochemical properties seem to not be affected by the tag protein probably due its small size. FLAG-tag, or FLAG octapeptide, a polypeptide consisting of eight aa’s (DYKDDDDK) can be added to a protein using recombinant DNA technology; therefore, the tag can be detected with the fused protein in many different assays that require recognition by an antibody.