Click chemistry armed enzyme-linked immunosorbent assay to measure palmitoylation by hedgehog acyltransferase
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Published version
Author(s)
Type
Journal Article
Abstract
Hedgehog signaling is critical for correct embryogenesis and tissue development. However, on maturation, signaling is also found to be aberrantly activated in many cancers. Palmitoylation of the secreted signaling protein sonic hedgehog (Shh) by the enzyme hedgehog acyltransferase (Hhat) is required for functional signaling. To quantify this important posttranslational modification, many in vitro Shh palmitoylation assays employ radiolabeled fatty acids, which have limitations in terms of cost and safety. Here we present a click chemistry armed enzyme-linked immunosorbent assay (click–ELISA) for assessment of Hhat activity through acylation of biotinylated Shh peptide with an alkyne-tagged palmitoyl-CoA (coenzyme A) analogue. Click chemistry functionalization of the alkyne tag with azido-FLAG peptide allows analysis through an ELISA protocol and colorimetric readout. This assay format identified the detergent n-dodecyl β-d-maltopyranoside as an improved solubilizing agent for Hhat activity. Quantification of the potency of RU-SKI small molecule Hhat inhibitors by click–ELISA indicated IC50 values in the low- or sub-micromolar range. A stopped assay format was also employed that allows measurement of Hhat kinetic parameters where saturating substrate concentrations exceed the binding capacity of the streptavidin-coated plate. Therefore, click–ELISA represents a nonradioactive method for assessing protein palmitoylation in vitro that is readily expandable to other classes of protein lipidation.
Date Issued
2015-09-01
Date Acceptance
2015-08-21
Citation
Analytical Biochemistry, 2015, 490, pp.66-72
ISSN
1096-0309
Publisher
Elsevier
Start Page
66
End Page
72
Journal / Book Title
Analytical Biochemistry
Volume
490
Copyright Statement
© 2015 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license
(http://creativecommons.org/licenses/by/4.0/).
(http://creativecommons.org/licenses/by/4.0/).
License URL
Sponsor
Cancer Research UK
Grant Number
C6433/A16402
Subjects
Science & Technology
Life Sciences & Biomedicine
Physical Sciences
Biochemical Research Methods
Biochemistry & Molecular Biology
Chemistry, Analytical
Chemistry
Hedgehog acyltransferase
Protein palmitoylation
Click chemistry
MBOAT
SONIC-HEDGEHOG
HUMAN-CELLS
CANCER PROGRESSION
PROTEIN LIPIDATION
INHIBITORS
PATHWAY
PROBES
0301 Analytical Chemistry
0601 Biochemistry And Cell Biology
0399 Other Chemical Sciences
Publication Status
Published