Monitoring Wnt Protein Acylation Using an In Vitro Cyclo-Addition Reaction

  • Rubina Tuladhar
  • Nageswari Yarravarapu
  • Lawrence LumEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1481)


We describe here a technique for visualizing the lipidation status of Wnt proteins using azide-alkyne cycloaddition chemistry (click chemistry) and SDS-PAGE. This protocol incorporates in vivo labeling of a Wnt-IgG Fc fusion protein using an alkynylated palmitate probe but departs from a traditional approach by incorporating a secondary cycloaddition reaction performed on single-step purified Wnt protein immobilized on protein A resin. This approach mitigates experimental noise by decreasing the contribution of labeling from other palmitoylated proteins and by providing a robust method for normalizing labeling efficiency based on protein abundance.

Key words

Wnt acylation Click chemistry Biotinylation Palmitoleate IgG fusion protein 



This work was supported by the NIH (R01 CA168761, R01CA196851), CPRIT (RP130212), and the Welch Foundation (I-1665).


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Rubina Tuladhar
    • 1
  • Nageswari Yarravarapu
    • 1
  • Lawrence Lum
    • 1
    Email author
  1. 1.Department of Cell BiologyUniversity of Texas Southwestern Medical CenterDallasUSA

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