For Research Use Only. Not for Clinical Use.

Creative Biolabs has a Ph.D.-level technical talent team, with more than ten years of profound technical precipitation and experimental operation experience in the field of drug half-life. We have successfully established a mature and efficient half-life technology platform, providing a variety of services including half-life assay by proteomic approaches.

Introduction of Proteomic Approaches

A proteome has been defined as the protein complement expressed by the genome of an organism, or, in multicellular organisms, as the protein complement expressed by tissue or differentiated cell, which is used both as a database archive and as a biological assay or biological research tool.

Mass spectrometry is a powerful tool for diverse protein analyses, but its application is mainly confined to qualitative approaches. The importance of quantitation in proteomics has recently become appreciated, mass spectrometric methods based on stable isotope quantitation were created such as stable isotope labeling in cell culture (SILAC), which showed great promise for the simultaneous and automated identification and quantitation of complex protein mixtures.

Since the expression of genes and gene products can vary between one tissue and another and this expression can be modulated by various inhibitory and stimulatory physiological signals, SILAC can provide an effective tool to follow protein synthesis, turnover, and degradation under various experimental and physiological conditions. Furthermore, the use of different isotopic versions of an amino acid can facilitate a temporal tracking of protein abundance.

Proteomics-based Assays for Detection of Proteins Half-lives

• Dynamic SILAC
  In a simple dynamic SILAC application scenario, cells can be grown in media supplemented with either non-labeled mino acids (light) or labeled amino acids (heavy) where the carbon and nitrogen atoms in selected amino acids are replaced with their heavier counterpart. The introduction of SILAC allows multiple groups of samples to be mixed and analyzed together and hence it would be possible to distinguish these samples during post-data collection analysis thus eliminating any systematic and human error because of sample handling. The use of different isotopic versions of an amino allows the temporal tracking of protein abundance.
• Pulse-chase-coupled with SILAC
  A pulse-chase assay coupled with SILAC can be performed to study the degradation kinetics of large number of proteins. Briefly, cells are grown in media containing either non-labeled or labeled amino acids and pulsed with a methionine analog before harvesting following multiple time points. This method facilitates the selective isolation of proteins by click chemistry and thus enhances the detection of the proteins synthesized during the initial pulse phase of the experiment only. This leads to the determination of the half-lives of rapidly degrading proteins.

Fig.1 Proteomics-based assays for studying proteins half-lives. (Eldeeb, 2019)

Creative Biolabs has an experienced technical team and can provide customers with complete solutions related to half-life assay, whether it is a one-stop service, or it can be delivered in stages. We expect to promote the research of innovative drugs with professional, personalized, and precise services. If you have any questions about half-life testing, please contact us for more information.

Reference

1. Eldeeb, M. A.; et al. A molecular toolbox for studying protein degradation in mammalian cells. Journal of neurochemistry. 2019,151(4): 520-533.