Stable isotope labeling by amino acids in cell culture

Silac

Stable isotope labeling by amino acids in cell culture

Stable isotope labeling by amino acids in cell culture (SILAC) is a technique used in proteomics to study protein dynamics and interactions within cells. SILAC involves the incorporation of stable isotope-labeled amino acids into proteins during cell culture, allowing for precise quantification and identification of proteins.

History

The SILAC method was first introduced in 2002 by Matthias Mann and colleagues as a way to overcome the limitations of traditional proteomic techniques. By using stable isotopes, researchers can distinguish between newly synthesized proteins and pre-existing proteins within a cell.

Methodology

In SILAC, cells are cultured in a medium containing amino acids labeled with stable isotopes such as carbon-13 and nitrogen-15. As the cells divide and grow, the labeled amino acids are incorporated into newly synthesized proteins. By comparing the mass spectra of labeled and unlabeled proteins, researchers can quantify changes in protein expression levels under different experimental conditions.

Applications

SILAC has been widely used in various areas of biological research, including studies of cell signaling, protein-protein interactions, and post-translational modifications. The technique has also been instrumental in identifying biomarkers for diseases such as cancer and neurodegenerative disorders.

Advantages

One of the key advantages of SILAC is its ability to provide quantitative information about protein expression levels in a highly reproducible manner. Additionally, SILAC allows for the identification of proteins that are differentially expressed under specific conditions, providing insights into cellular processes and pathways.

Limitations

While SILAC is a powerful tool for proteomic analysis, it does have some limitations. For example, the technique may not be suitable for all cell types or experimental conditions, and the cost of labeled amino acids can be prohibitive for some research labs.

See also

• Proteomics
• Mass spectrometry
• Isotope labeling
• Cell culture