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Updated: Jul 31, 2026
11:36
Glycan Node Analysis: A Bottom-up Approach to Glycomics
Published on: May 22, 2016
ADAMTS-13 glycans and conformation-dependent activity
A A Nowak1, H E R O'Brien1, P Henne1
1Department of Haematology, Faculty of Medicine, Hammersmith Hospital Campus, Imperial College London, London, UK.
Journal of Thrombosis and Haemostasis : JTH
|April 4, 2017
Summary
N-linked glycosylation significantly impacts ADAMTS-13 activity. Terminal sialic acid on metalloprotease domain glycans and CUB domain glycans are crucial for regulating ADAMTS-13 function under various conditions.
Area of Science:
- Biochemistry
- Molecular Biology
- Proteomics
Background:
- ADAMTS-13 (A Disintegrin and Metalloproteinase with Thrombospondin type 1 repeats, member 13) activity is modulated by its conformation, influenced by interactions between C-terminal CUB domains and the spacer domain.
- ADAMTS-13 possesses 10 N-linked glycosylation sites, with four located in the TSP2 to CUB domains, potentially affecting its conformation and function.
Purpose of the Study:
- To investigate the impact of N-linked glycosylation on ADAMTS-13 conformation and proteolytic activity.
- To determine the role of specific glycosylation sites and terminal sialic acid in ADAMTS-13 function under static and shear stress conditions.
Main Methods:
- Assessed proteolytic activity of glycan-modified ADAMTS-13 against FRETS-VWF73 and full-length von Willebrand factor (VWF) under static and shear stress.
- Utilized enzymatic deglycosylation and site-directed mutagenesis (N-linked glycan site variants) to study the effects of glycosylation.
- Employed immunoprecipitation to analyze protein interactions and antibody binding.
Main Results:
- Enzymatic removal of terminal sialic acid or N-linked glycans reduced ADAMTS-13 activity under static and shear stress conditions.
- N-linked glycans in the metalloprotease domain (via sialic acid) and CUB domains are critical for optimal ADAMTS-13 function.
- Mutations in CUB domain glycans (N1235Q, N1354Q) enhanced activity under shear stress and reduced interaction with the spacer domain, while mutations in TSP2/TSP4 domains (N707Q, N828Q) reduced activity under static conditions.
Conclusions:
- N-linked glycosylation is a key regulator of ADAMTS-13 activity, influencing its conformation and substrate interaction.
- Specific glycosylation sites, particularly those in the metalloprotease and CUB domains, play distinct roles in modulating ADAMTS-13 function.
- Understanding these glycosylation impacts is crucial for comprehending ADAMTS-13's role in hemostasis and thrombosis.
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