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Updated: Feb 17, 2026

In Vitro Analysis of E3 Ubiquitin Ligase Function
Published on: May 14, 2021
Regulation of the Tumor-Suppressor BECLIN 1 by Distinct Ubiquitination Cascades
Fahd Boutouja1, Rebecca Brinkmeier2, Thomas Mastalski3
1Biochemie Intrazellulärer Transportprozesse, Ruhr-Universität Bochum, 44801 Bochum, Germany. fahd.boutouja@rub.de.
Abstract:
Autophagy contributes to cellular homeostasis through the degradation of various intracellular targets such as proteins, organelles and microbes. This relates autophagy to various diseases such as infections, neurodegenerative diseases and cancer. A central component of the autophagy machinery is the class III phosphatidylinositol 3-kinase (PI3K-III) complex, which generates the signaling lipid phosphatidylinositol 3-phosphate (PtdIns3P). The catalytic subunit of this complex is the lipid-kinase VPS34, which associates with the membrane-targeting factor VPS15 as well as the multivalent adaptor protein BECLIN 1. A growing list of regulatory proteins binds to BECLIN 1 and modulates the activity of the PI3K-III complex. Here we discuss the regulation of BECLIN 1 by several different types of ubiquitination, resulting in distinct polyubiquitin chain linkages catalyzed by a set of E3 ligases. This contribution is part of the Special Issue "Ubiquitin System".
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