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Advancing formaldehyde cross-linking towards quantitative proteomic applications

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Abstract

Formaldehyde is a key fixation reagent. This review explores its application in combination with qualitative and quantitative mass spectrometry (MS). Formalin-fixed and paraffin-embedded (FFPE) tissues form a large reservoir of biologically valuable samples and their investigation by MS has only recently started. Furthermore, formaldehyde can be used to stabilise protein–protein interactions in living cells. Because formaldehyde is able to modify proteins, performing MS analysis on these samples can pose a challenge. Here we discuss the chemistry of formaldehyde cross-linking, describe the problems of and progress in these two applications and their common aspects, and evaluate the potential of these methods for the future.

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Acknowledgments

The authors would like to acknowledge the Natural Sciences and Engineering Research Council of Canada for financial support of the formaldehyde cross-linking work performed in their laboratory, and the Canadian Institutes for Health Research and the Canadian Breast Cancer Foundation for general funding. The authors would also like to thank the referees for their instructive comments.

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Authors and Affiliations

  1. The Biomedical Research Centre, University of British Columbia, 2222 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada

    Cordula Klockenbusch, Jane E. O’Hara & Juergen Kast

  2. Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada

    Juergen Kast

  3. Centre for Blood Research, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada

    Juergen Kast

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  1. Cordula Klockenbusch
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  2. Jane E. O’Hara
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Correspondence to Juergen Kast.

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Published in the topical issue Quantitative Mass Spectrometry in Proteomics with guest editors Bernhard Kuster and Marcus Bantscheff.

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Klockenbusch, C., O’Hara, J.E. & Kast, J. Advancing formaldehyde cross-linking towards quantitative proteomic applications. Anal Bioanal Chem 404, 1057–1067 (2012). https://doi.org/10.1007/s00216-012-6065-9

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