糖心视频

Proteins have specific biological functions in cells through conformational changes and interactions. Therefore, precise, in situ analysis of protein complex changes is essential for understanding cellular functions, uncovering disease mechanisms, and identifying potential drug targets.

In vivo cross-linking mass spectrometry (XL-MS) has emerged as a powerful technique to study protein complexes in living cells. However, during the enrichment of cross-linked peptides, complicated steps cause considerable sample loss, which limits the analysis of limited samples and hampers the reproducibility in quantitative analysis.

In a study published in , a team led by Prof. Zhang Lihua from the Dalian Institute of Chemical 糖心视频ics (DICP) of the Chinese Academy of Sciences developed a novel dimethylpiperidine-based cross-linker that enables one-step enrichment and quantitative analysis of protein complexes.

Using dimethylpiperidine as the enrichment handle, the researchers designed a cross-linker, 2,6-dimethylpiperidine disuccinimidyl tridecanoate (DPST). DPST exhibited cell membrane permeability, enrichment capability, and quantitative functionality.

By leveraging tandem mass tag antibodies, DPST enabled one-step enrichment and reversible elution of cross-linked peptides, eliminating sample loss from traditional multi-step processes. This allowed in vivo XL-MS analysis using as few as 10,000 cells.

Moreover, DPST supported light and heavy isotope labeling at the cellular level, and improved signal-to-noise ratio via MS2 quantitative reporter ions without increasing spectral complexity.

Using this novel cross-linker, researchers successfully mapped the protein interaction network in primary neurons derived from a single-embryo mouse. They also achieved quantitative detection of transient and weak interactions within dynamic liquid-liquid phase separation environments.

"By addressing key limitations in in vivo cross-linking proteomics, DPST provides a powerful solution for both qualitative and quantitative XL-MS analysis, with strong potential to drive advances in biomedical research and drug discovery," said Prof. Zhang.