Related Experiment Video
Updated: Jun 12, 2025

06:06
In Vitro Analysis of E3 Ubiquitin Ligase Function
Published on: May 14, 2021
5.1K
Targeted protein degradation using chimeric human E2 ubiquitin-conjugating enzymes.
Jonathan D Taylor1, Nathalie Barrett2, Sergio Martinez Cuesta3
1Biologics Engineering, R&D Oncology, AstraZeneca, Cambridge, CB2 0AA, UK. jonathan.taylor@astrazeneca.com.
Communications Biology
|September 19, 2024
Summary
Researchers developed novel E2 bioPROTACs that degrade intracellular proteins SHP2 and KRAS by recruiting them to ubiquitin-conjugating enzymes. This approach offers a new strategy for targeted protein degradation.
Area of Science:
- Biochemistry
- Molecular Biology
- Drug Discovery
Background:
- Targeted protein degradation is a therapeutic strategy.
- Biological Proteolysis-Targeting Chimeras (bioPROTACs) utilize E3 ligases for protein degradation.
- E2 ubiquitin-conjugating enzymes are crucial in the ubiquitination pathway.
Purpose of the Study:
- To engineer novel protein degraders by recruiting target proteins to E2 enzymes.
- To develop E2 bioPROTACs for the degradation of SHP2 and KRAS.
- To compare E2-based and VHL-based bioPROTACs using proteomics.
Main Methods:
- Rational design and screening of E2 bioPROTACs.
- Fusion of target-binding domains to human E2 enzymes.
- Global proteomics to analyze degradation effects.
- Protein display libraries for degrader discovery.
Main Results:
- Developed E2 bioPROTACs that induce degradation of SHP2 and KRAS.
- Characterized target-specific and global effects of E2 vs. VHL bioPROTACs.
- Identified a weak-affinity degrader via protein display that suppresses SHP2 signaling.
Conclusions:
- E2 bioPROTACs are a viable strategy for targeted protein degradation.
- This approach offers an alternative to E3 ligase-based systems.
- Protein display libraries can identify effective bioPROTACs with lower affinity.
Related Concept Videos
Regulated Protein Degradation
7.2K
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
7.2K
The Proteasome
818
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
818
Export of Misfolded Proteins out of the ER
3.5K
After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...
3.5K
Receptor Downregulation in MVBs
2.0K
Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR...
The EGFR can initiate signaling pathways that lead to cell proliferation, migration, and differentiation. Overexpression of EGFR stimulates cells to proliferate. Excessive EGFR...
2.0K
The Unfolded Protein Response
4.5K
The ER is the hub of protein synthesis in a cell. It has robust systems to quality control protein folding and also for degradation of terminally misfolded proteins. Under normal conditions, a small proportion of misfolded proteins that cannot be salvaged need to be transported to the cytoplasm by the ER-associated degradation or ERAD pathways. However, if the ERAD cannot handle the misfolded proteins, the cell activates the unfolded protein response or UPR to adjust the protein folding...
4.5K
Tagging and Fusion Proteins
6.6K
Proteins are involved in several cellular processes and biochemical reactions. Analyzing a specific protein of interest requires it to be isolated from the other proteins in the cell. This is achieved by overexpressing the specific gene in a suitable host to produce large quantities of the target protein. A tag or label is recombined with the gene to produce a fusion protein containing the target protein and the tag. The tags on these fusion proteins can then be used for easy detection and...
6.6K

