Breakthrough in Protein Degradation Technology Reveals Molecular Mechanisms for Targeting 'Undruggable' Diseases
Key Insights
Researchers at the University of Dundee used cryo-electron microscopy and AI to reveal previously invisible molecular details of how protein degrader drugs work, showing how they position disease-causing proteins for destruction.
The study demonstrates how protein degraders capture disease-causing proteins and position them for effective tagging by ubiquitin (search) molecules, which marks them for cellular destruction.
This breakthrough provides unprecedented molecular-level understanding that could accelerate development of new targeted protein degradation (search) drugs for diseases previously considered 'undruggable'.
Researchers at the University of Dundee have achieved a breakthrough in understanding how protein degrader molecules work at the molecular level, revealing previously invisible details that could accelerate the development of drugs for diseases previously considered "undruggable." The findings, published in Science Advances, provide unprecedented insight into the mechanisms of targeted protein degradation (search), a revolutionary approach with more than 50 drugs currently in clinical trials.
Revolutionary Visualization of Protein Degradation
PhD student Charlotte Crowe and Dr Mark Nakasone at the Centre for Targeted Protein Degradation (search) (CeTPD) used cryo-electron microscopy combined with artificial intelligence to generate 3D snapshots of degrader drugs in action. This technique involves flash-freezing proteins and using focused electron beams to capture millions of 2D images, which sophisticated software then assembles into moving 3D models.
"We have reached a level of detail where we can see how these protein degraders work and can be deployed [to recruit the disease-causing protein] and target the 'bull's eye', in molecular terms," said Charlotte Crowe. "Proteins are typically a few nanometres large, which is 1 billionth of a metre, or 1 millionth of the width of a hair. So being able to 'see' them in action has not been possible, up until now."
Molecular Mechanism Revealed
The research demonstrates how protein degraders function fundamentally differently from conventional drugs. Rather than simply blocking protein function, these molecules redirect the cell's natural protein recycling systems to destroy disease-causing proteins entirely. The process involves capturing the target protein and positioning it to receive ubiquitin (search) "tags" - small proteins that mark the target for destruction by cellular machinery.
Working with a protein degrader molecule called MZ1, developed in the Ciulli laboratory at Dundee, the team used high-end mass spectrometry to identify exactly where ubiquitin (search) tags are added to target proteins. The study shows that degradation efficiency depends on the degrader molecule's ability to hold tightly onto the disease-causing protein in the optimal position for ubiquitin attachment.
"Protein degraders work by capturing the disease-causing protein and making it stick like a glue to the cellular protein-recycling machinery, which then tags the protein as expired in order to destroy it," explained the researchers. The ubiquitin (search) tag "gets fired at the disease-causing protein like a bullet" and must hit the right spots for effective tagging.
Clinical Implications and Future Development
Professor Alessio Ciulli, Director of CeTPD and a world leader in targeted protein degradation (search), emphasized the clinical significance of these findings. "This is incredibly exciting work and opens up the possibility of even more effectively targeted drugs able to finally treat some diseases which up until now have been too difficult to tackle."
The research addresses a critical limitation in drug development, as many disease-related proteins lack the structural features that conventional drugs require to function effectively. Targeted protein degradation (search) offers a solution by eliminating these "undruggable" proteins entirely rather than attempting to inhibit their function.
Advancing the Field
Professor Ciulli noted that this work, along with complementary research from laboratories led by Brenda Schulman at the Max-Planck Institute of Biochemistry and Gary Kleiger at the University of Nevada, Las Vegas, represents a collective leap forward in understanding cellular protein-recycling machinery. "Our collective work provides a leap forward in understanding that will accelerate development of new TPD drugs in future," he said.
The ability to visualize and control protein degradation with "an incredible level of detail" represents a significant advancement for the field, potentially enabling more precise and effective therapeutic interventions for diseases that have previously resisted treatment approaches.