Summary: Co-immunoprecipitation (Co-IP) is a popular technique for the analysis of protein interaction. The procedure includes: 1) An antibody specific to the protein of interest is added to a cell lysate. 2) The antibody-protein complex is then precipitated usually using protein-G or protein-A sepharose which binds most antibodies. If there are any protein/molecules that bind to the first protein, they will also be precipitated. 3) Co-precipitated protein can then be identified by Western blot analysis or by sequencing a purified protein band.
- Co-Immunoprecipitation Assays (Lykke-Andersen Lab, Department of MCD Biology, University of Colorado)
Co-IP assays can be performed between endogenous proteins or transiently or stably expressed exogenous - usually tagged - proteins. The advantage to using endogenous proteins is the avoidance of protein overexpression and tagging that can lead to artifacts. The advantage to using exogenously expressed tagged proteins is the generally high specificity of the anti-tag antibody and the ease with which a negative control can be performed in which the exogenous protein is lacking.
Added: Sat Jan 31 2009, Hits: 20852, Reviews: 0
It is a good start to learn what is Co-IP and how it works
Added: Sat Jan 31 2009, Hits: 17628, Reviews: 0
Co-Immunoprecipitation Analysis of Protein-Protein Interaction
(Morrisey Lab, University of Pennsylvania)
This protocol uses total cell extracts to analyze putative protein-protein interactions in eukaryotic cells. One can also use nuclear extracts as a source for this protocol.
Added: Mon Oct 14 2002, Hits: 19373, Reviews: 0