Development of a sensitive peptide-based immunoassay: application to detection of the Jun and Fos oncoproteins

The peptide-based ELISA test for assessing dimerization affinities of Jun and Fos protein complexes is simple, rapid and sensitive. c-Jun and c-Fos preferentially form heterodimers by using leucine zipper domains. Recombinant Jun leucine zipper peptides bind to a fosLZ-glutathione S-transferase fusion protein. Jun:Fos complexes are detected through enzyme complex amplification. This ELISA system enables the detection of subanomolar concentrations of Jun and Fos, and determination of dissociation constants for complex formation.