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bioRxiv · 10.1101/2021.07.30.454285

Development of a compact alkynyl-enrichable crosslinker for in-depth in-vivo crosslinking analysis

Gao, H.·Zhao, L. L.·Zhao, Q.·Zhang, H. L.·Zhao, F. B.·Gong, Z.
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Abstract

Chemical crosslinking coupled with mass spectrometry (CXMS) has emerged as a powerfl technique to capture the dynamic information of protein complexes with high sensitivity, throughput and sample universality. To advance the study of in-vivo protein structures and protein-protein interactions on the large scale, a new alkynyl-enrichable crosslinker was developed with high efficiency of membrane penetration, reactivity and enrichment. The crosslinker was successfully used for in-vivo crosslinking of intact human cells, reslting in 6820 non-redundant crosslinks identified at a false discovery rate (FDR) of 1% using pLink 2.0, which 4898 (71.8%) of the cross-links were assigned as intraprotein and 1922 (28.2%) were interprotein links. To our knowledge, this is also the first time to realize the in-vivo crosslinking with a non-cleavable crosslinker for homo species cells.

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Gao, H., Zhao, L. L., Zhao, Q., Zhang, H. L., Zhao, F. B., Gong, Z.. 2021-07-30. Development of a compact alkynyl-enrichable crosslinker for in-depth in-vivo crosslinking analysis. https://doi.org/10.1101/2021.07.30.454285

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