Revolutionizing mRNA Therapeutics: NUS Breakthrough in Rigid Folding Architecture
In a groundbreaking advancement published today in Nature Nanotechnology, researchers from the National University of Singapore (NUS) have unveiled a novel strategy called metal-ion-assisted RNA folding (MARF) that dramatically boosts protein production from messenger RNA (mRNA). This innovation addresses key limitations in mRNA therapeutics, where inefficient protein expression has hindered applications beyond vaccines, such as gene editing and protein replacement therapies. Led by Assistant Professor Qianqian Ni from NUS Yong Loo Lin School of Medicine's Department of Diagnostic Radiology and Nanomedicine Translational Research Program, the team demonstrates up to a 7.3-fold increase in protein yield through engineered rigid mRNA tertiary structures facilitated by specific metal ions delivered via lipid nanoparticles (LNPs).
The study highlights how MARF alters the mechanical properties of mRNA-LNP complexes, improving endosomal escape, intracellular processing, and cellular retention. This positions NUS at the forefront of Singapore's burgeoning biotech ecosystem, where mRNA research is pivotal to the nation's Research, Innovation, and Enterprise 2020 plan extended into 2030.
Understanding mRNA Therapeutics and Their Rise in Singapore
Messenger RNA (mRNA) serves as a blueprint for protein synthesis in cells. Discovered in the early 1960s, mRNA therapeutics gained prominence with COVID-19 vaccines from Moderna and BioNTech/Pfizer, which instructed cells to produce viral spike proteins, training the immune system. Post-pandemic, the global mRNA therapeutics market is projected to reach USD 159.59 billion by 2031, growing at 16.5% CAGR, driven by applications in cancer, rare diseases, and regenerative medicine.
In Singapore, NUS and A*STAR lead mRNA innovation, supported by the Nucleic Acid Therapeutics Initiative (NATi) and collaborations like Flagship Pioneering with NUS and National University Hospital. These efforts align with Singapore's goal to be a biotech hub, contributing 30% to APAC mRNA R&D. NUS researchers, including those from the Mechanobiology Institute, leverage interdisciplinary expertise in nanotechnology and immunology.
Key Challenges in mRNA Protein Production Efficiency
While mRNA vaccines succeeded against infectious diseases, extending them to chronic conditions faces hurdles. Primary issues include rapid degradation by ribonucleases, poor translation efficiency (often yielding only 10^3-10^6 proteins per mRNA), immunogenicity, and suboptimal delivery. Secondary structures like hairpins improve stability, but tertiary structures—3D folds involving long-range base pairing—remain underexplored despite influencing ribosome access and nuclear export.
Lipid nanoparticles (LNPs), the gold standard delivery vehicle, protect mRNA but struggle with endosomal entrapment, where 99% of particles fail to escape, limiting cytosolic release. Inefficient protein production hampers therapeutic dosing, requiring high amounts that raise costs and side effects. Statistics show only 1-2% of delivered mRNA translates effectively in non-hepatic tissues, underscoring the need for innovations like MARF.
The MARF Strategy: Engineering Rigid mRNA Folds with Metals
The NUS team's metal-ion-assisted RNA folding (MARF) introduces specific divalent metals (e.g., Mn2+, Mg2+) to induce rigid tertiary mRNA architectures within LNPs. Unlike flexible mRNA, rigid folds mimic stable viral RNAs, enhancing mechanical rigidity of LNPs. This rigidity facilitates better interactions with cellular endosomes, promoting escape and prolonged retention.
Step-by-step: 1) Design mRNA sequences prone to metal coordination. 2) Encapsulate with LNPs containing metals. 3) Metals bridge phosphate backbones, stabilizing 3D folds (confirmed via cryo-TEM and simulations). 4) Rigid LNPs deform endosomes efficiently. 5) mRNA released, processed faster, yielding more proteins. Collaborators from Jilin University and Nanjing University contributed simulations validating mechanics.
Experimental Breakthroughs: Up to 7.3-Fold Protein Boost
In vitro, Mn-MARF mRNA in LNPs produced 7.3-fold more luciferase protein in hepatocytes vs. controls, with polysome profiling showing increased ribosome loading. In vivo mouse models confirmed amplified translation in liver (Fig. 5 of the study). Therapeutic Cre recombinase expression lasted longer, enabling robust gene editing.
For clinically relevant proprotein convertase subtilisin/kexin type 9 (PCSK9)—a liver protein degrading LDL receptors—single IV dose MARF LNPs with CRISPR-Cas9 achieved durable knockout, reducing serum PCSK9 by over 80% persistently (Fig. 6). This outperforms traditional LNPs, promising hypercholesterolemia treatments without repeat dosing.
Photo by Invest Europe on Unsplash
Mechanical Insights: Why Rigidity Matters in Delivery
Molecular dynamics simulations revealed rigid MARF LNPs exert higher tension on endosomal membranes, aiding escape. Flexible LNPs aggregate or degrade faster. NUS Mechanobiology Institute's expertise (Jie Yan et al.) quantified this: rigid particles translocate cytosol 2-3x faster. Prolonged nuclear/perinuclear retention stabilizes mRNA against exonucleases.
- Endocytosis: Rigid LNPs favor clathrin pits.
- Escape: Membrane deformation threshold met efficiently.
- Retention: Reduced diffusion, higher translation.
This mechanical paradigm shifts mRNA design from sequence to structure-function.
Applications Beyond Vaccines: Gene Editing and Protein Replacement
MARF excels for liver-targeted therapies. PCSK9 editing exemplifies cardiovascular applications; similar potential for ANGPTL3 (triglycerides). In oncology, higher neoantigen production could enhance cancer vaccines. Rare diseases benefit from sustained protein expression, reducing dosing frequency.Read the full Nature Nanotechnology study
Singapore's NATi funds such platforms, bridging academia-industry for clinical translation.
NUS and Singapore's Biotech Momentum
NUS, Asia's top university (QS 2026 #8 globally), invests heavily in nanomedicine. Qianqian Ni's lab pioneers RNA delivery; funding from NMRC, MOE, A*STAR supports. Singapore's biotech sector, valued at billions, hosts 7 key firms, with RIE2030 allocating S$25B for R&D. Collaborations like SCG Cell Therapy-A*STAR accelerate mRNA manufacturing.
This MARF advance reinforces NUS's role, attracting talent to higher ed jobs in biotech.
Future Outlook: Scaling MARF for Clinical Impact
Challenges remain: metal biocompatibility, off-target folding, scalability. NUS plans human trials via NUHS partnerships. Broader impacts include personalized mRNA for CRISPR therapies. With APAC's 30% mRNA share, Singapore leads via innovations like MARF.
Explore NUS faculty opportunities at professor jobs or career advice on writing academic CVs.
Stakeholder Perspectives and Broader Implications
Experts praise MARF's elegance; Qianqian Ni notes, "Mechanical cues unlock mRNA's full potential." Industry sees cost reductions (lower doses), patients gain durable treatments. Ethically, equitable access vital in Singapore's diverse society.
For aspiring researchers, research assistant jobs at NUS abound. Rate professors at Rate My Professor.
Photo by Vitaly Gariev on Unsplash
Dr. Ni's MARF innovation cements NUS's biotech leadership. Aspiring academics, check higher ed jobs, university jobs, rate professors, and career advice. Post jobs at Post a Job.
