Proteins are the performers and regulators of most cellular activities. They usually interact with neighboring proteins and form multi-protein complexes, or respond to intra- and intercellular signals. There are currently some methods to broadly understand the interaction network, such as genome-wide yeast two-hybrid screening and protein arrays. However, the yeast two-hybrid system only produces binary interactions, while the protein array is relatively time-consuming and laborious. These deficiencies may limit their application in the purification of large-scale protein complexes.
A protein complex purification strategy called Tandem Affinity Purification (TAP) has been developed, which can identify interaction partners and purify protein complexes when combined with mass spectrometry. In this method, the TAP tag is fused to the protein of interest (at the C-terminus or N-terminus) and transformed into appropriate host organisms. Protein complexes containing TAP-labeled proteins can be purified from cell extracts through two specific affinity purification steps. Based on the advantages of fast, reproducible, and high specificity of this method, it has been successfully applied to the study of protein-protein interactions in both prokaryotic and eukaryotic cells.
Figure 1. Schematic of the original TAP method (Xu, X.; et al. 2010)
Creative Proteomics has established a high-quality and efficient TAP platform, and has accumulated a lot of experience in this field. The platform we provide can be used for protein-protein interaction and protein complex research including yeast, mammals, plants, drosophila, bacteria, and other organisms. In addition to regular TAP experiments, our experts can also conduct customized experiments according to different project requirements. For example, we can provide several optimized dual-affinity tags for mammalian cell systems, which increase the yield of protein complexes and improve specificity. In response to the competition between endogenous proteins and tagged proteins in the assembly of protein complexes, we can provide RNAi to reduce the expression level of endogenous proteins. This strategy has been proven to be of great help to insect cell systems.
Customers can choose different technology platforms according to project requirements, or contact us directly for consultation, and our expert team will provide you with customized experimental procedures.
Creative Proteomics is an international biotechnology company dedicated to research in molecular interactions and other related fields. The tandem affinity purification platform we constructed has the characteristics of high quality and efficiency, and the data obtained can be directly used for paper publication. Our one-stop service aims to save customers time and money.