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Updated: May 27, 2026

A High-Throughput Luciferase Assay to Evaluate Proteolysis of the Single-Turnover Protease PCSK9
Published on: August 28, 2018
Role of ubiquitination in PCSK9-mediated low-density lipoprotein receptor degradation
1Department of Endocrine Research, Lilly Research Laboratories, Eli Lilly & Company, Indianapolis, IN 46285, USA.
Abstract:
The proprotein convertases subtilisin kexin 9 (PCSK9) binds to the epidermal growth factor domain A (EGF-A) of low-density lipoprotein receptor (LDLR) and leads to its destruction. However, the intracellular processes leading to LDLR degradation have not been fully delineated. In this report, we show that PCSK9 treatment can lead to ubiquitination of LDLR, which was enhanced in the presence of proteasome inhibitor MG132. Furthermore, LDLR protein carrying mutations in the C-terminal ubiquitination sites was resistant to PCSK9-mediated degradation. Our data suggest that the ubiquitination system is involved in PCSK9-induced LDLR degradation.
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