Multiple epitope tagging of expressed proteins for enhanced detection

Biotechniques. 2000 Apr;28(4):789-93. doi: 10.2144/00284pf01.

Abstract

Three FLAG epitopes have been incorporated into the mammalian expression vector pCMV-5 to create a transient expression vector, p3XFLAG-CMV-7. The vector was designed to express FLAG fusion proteins that can be detected at tenfold lower expression levels than the current FLAG fusion protein expression system. The usefulness of this expression and detection system was demonstrated by expression of bacterial alkaline phosphatase in COS-7 cells. In addition, 3XFLAG bacterial alkaline phosphatase was expressed in Escherichia coli, purified on anti-FLAG M2 affinity gel, and detection of 500 pg of purified protein by Western blot analysis is demonstrated.

Publication types

  • Comparative Study

MeSH terms

  • Alkaline Phosphatase / genetics
  • Alkaline Phosphatase / metabolism
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Blotting, Western
  • COS Cells
  • Chromatography, Affinity
  • Cytomegalovirus / genetics
  • Epitopes / genetics*
  • Epitopes / immunology
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Genetic Vectors / chemistry
  • Genetic Vectors / genetics*
  • Molecular Sequence Data
  • Oligopeptides
  • Peptides / genetics
  • Peptides / metabolism
  • Protein Biosynthesis*
  • Proteins / genetics*
  • Proteins / immunology
  • Recombinant Fusion Proteins / biosynthesis*
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Transfection

Substances

  • Epitopes
  • Oligopeptides
  • Peptides
  • Proteins
  • Recombinant Fusion Proteins
  • FLAG peptide
  • Alkaline Phosphatase