Co-immunoprecipitation

 (co-IP) is a popular technique to identify physiologically relevant protein–protein interactions by using target protein-specific antibodies to indirectly capture proteins that are bound to a specific target protein.

protein complex is isolated by Co-IP using an antibody for one of the components in the complex.

The choice of antibody is critical for successful Co-IP. The antibody must bind to the surface of the complex. Alternatively, a component is tagged, and IP is performed using an anti-tag antibody. In either case, the method of cell lysis and the conditions of washing should be carefully evaluated because components in protein complexes are often held in place by weak interactions.

A common approach is to optimize the condition for Co-IP using a tagged protein, which is easy to detect, and then perform Co-IP experiments with endogenous proteins.

[Related topics] Pull-down assay experiments using Tagged protein purification kits

Complex formation identified by Co-IP should be confirmed by other methods, such as analysis of protein interactions in vivo using fluorescent-labeled proteins.

[Related topics] Protein-Protein Interaction analysis tool "Fluoppi"

[Related topics] Protein-Protein Interaction Detection System "CoralHue™ Fluo-chase Kit"

Application :-

What can co-immunoprecipitation be used to study?

Co-immunoprecipitation can be utilized to study protein-protein interactions from various environments, cell types, or tissues. Herein, we describe a co-immunoprecipitation protocol that can be used to examine protein complexes found in the pathogenic spirochete Borrelia burgdorferi

immunoprecipitation (IP), an antibody is used to purify its specific target, or antigen from a mixture. In co-immunoprecipitation (Co-IP), an antibody is used to purify its target antigen, along with its binding partners, from a mixed sample