For decades, RNA has been seen primarily as a messenger—carrying genetic instructions between DNA and the machinery that makes proteins. But recent research has upended this view, revealing that RNA is capable of assembling into large, sophisticated structures entirely on its own.
This surprising discovery, led by teams at SLAC and Stanford, is changing how scientists think about the architecture and potential of RNA within cells.
Uncovering the Unexpected
- Surprising RNA Complexes:
By focusing on three abundant non-coding RNAs in bacteria, researchers discovered that these molecules can self-assemble into large, multistranded formations. Using cryogenic electron microscopy (cryo-EM), they observed structures far more intricate than previously thought possible without protein support. - Unique Shapes and Functions:
Two of the RNAs formed elaborate cages made of eight and fourteen RNA strands, hinting at possible roles in encapsulating other molecules. Another created a diamond-shaped scaffold, where two RNA strands met in a “kiss,” suggesting it might act as a molecular sensor. - Challenging Old Assumptions:
Previously, scientists believed that proteins were essential for building large molecular complexes. This research demonstrates that RNA alone can create stable, functional assemblies, forcing a reevaluation of RNA’s place in the molecular hierarchy. - Breakthrough Imaging:
The team’s use of advanced cryo-EM at SLAC enabled them to visualize these RNA-only structures in unprecedented detail. These results highlight cryo-EM’s potential for exploring the world of RNA, not just proteins.
Why This Matters
- Potential Roles in Cells:
Although the exact functions of these ornate RNA structures remain unknown, their unique forms—like cages and sensors—suggest specialized roles. They may be involved in molecular transport, regulation, or other processes yet to be uncovered. - Blueprints for Synthetic Biology:
Understanding how RNAs self-assemble could revolutionize fields like drug delivery, medical imaging, and molecular sensing. Scientists might use these principles to design custom RNA nanostructures for medical or industrial use. - Improved RNA Modeling:
These discoveries add valuable data for refining computational tools used to predict RNA folding. Better predictive models could aid in the design of RNA-based therapeutics and research tools.
What’s Next?
The research teams are now looking to identify whether these RNA complexes interact with other cellular molecules and to determine their precise biological functions. As exploration continues, the hope is to unlock new ways to engineer RNA for biotechnology, medicine, and beyond.
This breakthrough challenges the traditional view of RNA as a simple messenger. By demonstrating RNA’s ability to self-assemble into complex, protein-free structures, scientists are opening a new frontier in molecular biology—one with far-reaching implications for future research and innovation.
Source: SLAC National Accelerator Laboratory, “SLAC, Stanford researchers discover large protein-free RNA structures,” May 6, 2025. Read the original article
RNA’s Hidden Structural Powers Are Changing Molecular Biology