Protein Interaction Mapping Service

Protein interactions mediate many biological processes and are important in many life processes such as catalysis, transport, and signaling and are fundamental to cell structure and function. It is estimated that over 80% of proteins do not act alone but in complexes, making the identification of protein interactions an important part of research in the post-genomic era, particularly protein interaction mapping.

Immunoprecipitation (IP) is a highly specific method for isolating proteins of interest (POIs) and their interactors from complex protein mixtures. Creative Biostructure can employ IP in conjunction with liquid chromatography-mass spectrometry (LC-MS) and chemical labeling to acquire the interaction network of your protein of interest, allowing for the comparison of networks across diverse experimental conditions.

Our Method for Mapping Protein Interactions

The main principle of IP and LC-MS is based on the affinity of specific antibodies or other affinity reagents to the target protein. IP is used to extract the interacting proteins from a complex sample and then perform mass spectrometry to identify the interacting proteins of the target protein.

In current IP and LC-MS experiments, we usually choose milder wash conditions to retain more weakly interacting proteins as well as unavoidable background and non-specific binding proteins, followed by screening for high-confidence protein interactions based on quantitative proteomics data, i.e. protein quantification matrix obtained from mass spectrometry assays, by comparing the protein quantification of the experimental group with that of the control group, filtering out background protein and non-specific binding.

Figure 1. Combined IP and LC-MS to map protein interactions.

With the help of antibody specificity, we first capture the interacting protein complexes of POI from cells/tissues using IP. Samples of IP are alkylated and trypsin digested to obtain peptides of POI and associated proteins. The peptides were isotopically labeled so that the samples could be combined into a single plexing scheme and quantified. The mixture is then analyzed hierarchically with the aid of LC-MS. The final data obtained will be processed and scored by us through a database to generate interaction plots, including the use of STRING.

The STRING database is a searchable database of known and predicted protein-protein interactions for 2,031 species, containing 9.6 million proteins and 13.8 million protein-protein interactions. It contains experimental data, results of text mining from PubMed abstracts, and synthesis of data from other databases, in addition to results predicted using bioinformatics methods.

Advantages of Our Protein Interaction Mapping Service

• Quantification from as few as 5 million cells / 20 ug of protein.
• Quantitative analysis of up to 18 samples with no missing values.

Applications of Our Protein Interaction Mapping Service

• Quantification of proteins of interest
• Protein-protein interactions
• Active site mapping

Ordering Process

Systematic analysis of the interactions of many proteins in biological systems is important for understanding how proteins work in biological systems, understanding the mechanisms of biological signaling and energy-matter metabolism in response to specific physiological states such as disease, and understanding the functional links between proteins, often in association with screening for key genes. Creative Biostructure can help you map protein interactions Please feel free to contact us to start your project.