Publication Date:
2015-03-04
Description:
Signalling by Wnt proteins is finely balanced to ensure normal development and tissue homeostasis while avoiding diseases such as cancer. This is achieved in part by Notum, a highly conserved secreted feedback antagonist. Notum has been thought to act as a phospholipase, shedding glypicans and associated Wnt proteins from the cell surface. However, this view fails to explain specificity, as glypicans bind many extracellular ligands. Here we provide genetic evidence in Drosophila that Notum requires glypicans to suppress Wnt signalling, but does not cleave their glycophosphatidylinositol anchor. Structural analyses reveal glycosaminoglycan binding sites on Notum, which probably help Notum to co-localize with Wnt proteins. They also identify, at the active site of human and Drosophila Notum, a large hydrophobic pocket that accommodates palmitoleate. Kinetic and mass spectrometric analyses of human proteins show that Notum is a carboxylesterase that removes an essential palmitoleate moiety from Wnt proteins and thus constitutes the first known extracellular protein deacylase.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4376489/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4376489/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kakugawa, Satoshi -- Langton, Paul F -- Zebisch, Matthias -- Howell, Steven A -- Chang, Tao-Hsin -- Liu, Yan -- Feizi, Ten -- Bineva, Ganka -- O'Reilly, Nicola -- Snijders, Ambrosius P -- Jones, E Yvonne -- Vincent, Jean-Paul -- 090532/Wellcome Trust/United Kingdom -- 090532/Z/09/Z/Wellcome Trust/United Kingdom -- 294523/European Research Council/International -- A10976/Cancer Research UK/United Kingdom -- C375/A10976/Cancer Research UK/United Kingdom -- G0900084/Medical Research Council/United Kingdom -- MC_U117584268/Medical Research Council/United Kingdom -- U117584268/Medical Research Council/United Kingdom -- WT093378MA/Wellcome Trust/United Kingdom -- WT099197MA/Wellcome Trust/United Kingdom -- England -- Nature. 2015 Mar 12;519(7542):187-92. doi: 10.1038/nature14259. Epub 2015 Feb 25.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉MRC's National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK. ; Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK. ; Glycosciences Laboratory, Imperial College London, Department of Medicine, Du Cane Road, London W12 0NN, UK. ; Cancer Research UK, London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK. ; Cancer Research UK, Clare Hall Laboratories, Blanche Lane, South Mimms, Potters Bar, Hertfordshire EN6 3LD, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25731175" target="_blank"〉PubMed〈/a〉
Keywords:
Acylation
;
Animals
;
Binding Sites
;
Carboxylesterase/chemistry/*metabolism
;
Drosophila Proteins/chemistry/*metabolism
;
Esterases/chemistry/genetics/*metabolism
;
Fatty Acids, Monounsaturated/metabolism
;
Glycosylphosphatidylinositols/metabolism
;
Glypicans/metabolism
;
Humans
;
Kinetics
;
Ligands
;
Mass Spectrometry
;
Models, Molecular
;
Protein Binding
;
Wnt Proteins/*chemistry/*metabolism
;
*Wnt Signaling Pathway
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
