Yuval Elani’s research while affiliated with Imperial College London and other places

Stimuli‐responsive polymeric vesicles offer a versatile platform for mimicking dynamic cell‐like behaviors for synthetic cell applications. In this study, thermally responsive polymeric droplets derived from poly(ethylene oxide)‐poly(butylene oxide) (PEO‐PBO) polymersomes, aiming to create synthetic cell models that mimic key biological functions are developed. Upon heating, the nanoscale vesicles undergo fusion, transforming into sponge‐like microscale droplets enriched with membrane features. By modulating the temperature, these droplets display dynamic properties such as contractility, temperature‐induced fusion, and cargo trapping, including small molecules and bacteria, thereby demonstrating their ability to dynamically interface with biological entities. The findings demonstrate the potential of our sponge‐like droplets in synthetic cell applications, contributing to the understanding of PEO‐PBO polymersomes’ unique characteristics, expanding the capabilities of synthetic cell structures, and representing an exciting possibility for advancing soft matter engineering to cell‐like behaviors.

Artificial cells serve as promising micro‐robotic platforms that replicate cellular features. One ubiquitous characteristic of living cells is compartmentalization of content in distinct and well‐defined locations. Herein, a microfluidic strategy to mimic compartmentalization is developed through the production of micron‐scale two and three compartment biomimetic microgels, where hydrogel compartment number, composition, size, and shape can be controlled. Our lab‐on‐chip system enables the incorporation of various synthetic organelles into spatially separated compartments within the microgels. This design concept allows for the introduction of a variety of individually triggered bioinspired behaviors, including protein capture, enzyme‐mediated content release, and stimuli‐triggered motility, each isolated in a distinct compartment enabling the use of the microgels as compartmentalized artificial cells. With this approach, the division of content and function seen in biological cells can be mirrored, which will underpin the generation of increasingly sophisticated and functional soft matter microdevices using bottom‐up synthetic biology principles.

Synthetic cells have emerged as a promising tool for understanding cellular processes and developing novel biotechnological applications. In this study, we engineer dynamic and biomimetic behaviours in polymersomes, aiming to create synthetic cells that mimic key biological functions. These vesicles exhibit a temperature-driven fusogenic property, enabling the transformation of nanoscale vesicles into microsized sponge-like polymeric droplets. These droplets, rich in membrane content, can act as synthetic cells analogues with the capability for controlled cargo release. Moreover, the thermoresponsive nature of our polymersomes makes them versatile components for the construction of lipid-based synthetic cells, allowing for controllable cargo release and dynamic organelle-like functionalities. We also demonstrate that the microscale polymer droplets possess biomimetic properties including contractility, a behaviour typically observed in biological systems. By modulating the temperature, it is possible to induce these contractile behaviours as well as other functions, including controlled fusion and efficient bacteria capture.

Encapsulating both biological and non-biological materials in lipid vesicles presents significant potential in both industrial and academic settings. When smaller than 100 nm, lipid vesicles and lipid nanoparticles are ideal...

Cell burden impacts the performance of engineered synthetic systems. For this reason, there is great interest toward the development of tools to track burden and improve biotechnology applications. Fluorogenic RNA aptamers are excellent candidates for live monitoring of burden because their production is expected to impose a negligible load on transcription resources. Here we characterise the performance of a library of aptamers when expressed from different promoters in E. coli . We find that aptamer relative performance is dependent on the promoter and the strain, and that, contrary to expectation, aptamer expression impacts host fitness. By selecting two of the aptamers with brighter output and lower impact, we then design an intracellular biosensor able to report on the activation of the burden response in engineered cells. The sensor developed here adds to the collection of tools available for burden mitigation and may support bioprocessing applications where improved host performance is sought.

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are neurodegenerative diseases that exist on a clinico-pathogenetic spectrum, designated ALS/FTD. The most common genetic cause of ALS/FTD is expansion of the intronic hexanucleotide repeat (GGGGCC) n in C9orf72. Here, we investigate the formation of nucleic acid secondary structures in these expansion repeats, and their role in generating condensates characteristic of ALS/FTD. We observe significant aggregation of the hexanucleotide sequence (GGGGCC) n , which we associate to the formation of multimolecular G-quadruplexes (mG4s) by using a range of biophysical techniques. Exposing the condensates to G4-unfolding conditions leads to prompt disassembly, highlighting the key role of mG4-formation in the condensation process. We further validate the biological relevance of our findings by detecting an increased prevalence of G4-structures in C9orf72 mutant human motor neurons when compared to healthy motor neurons by staining with a G4-selective fluorescent probe, revealing signal in putative condensates. Our findings strongly suggest that RNA G-rich repetitive sequences can form protein-free condensates sustained by multimolecular G-quadruplexes, highlighting their potential relevance as therapeutic targets for C9orf72 mutation-related ALS/FTD. Amyotrophic lateral sclerosis (ALS) is rapidly progressive, uniformly fatal and untreatable due largely to an incomplete understanding of disease mechanisms. The lifetime risk of ALS is 1:300-1:400, and over an aggressive disease course, patients become paralysed, unable to eat, speak and breathe with an average survival of between 3-5 years 1. Frontotemporal dementia (FTD) is the second most common cause of dementia in patients less than 65 years old and is increasingly recog-nised to share clinical, genetic and pathomechanistic features with ALS, termed ALS/FTD 2. ALS and FTD, much like other neurodegen-erative diseases, are characterised by the presence of pathological aggregates in neurons. Many existing studies have predominantly focused on the protein component as the leading aggregation trigger 3 ,

Eukaryotic cells are characterized by multiple chemically distinct compartments, one of the most notable being the nucleus. Within these compartments, there is a continuous exchange of information, chemicals, and signaling molecules, essential for coordinating and regulating cellular activities. One of the main goals of bottom–up synthetic biology is to enhance the complexity of synthetic cells by establishing functional compartmentalization. There is a need to mimic autonomous signaling between compartments, which in living cells, is often regulated at the genetic level within the nucleus. This advancement is key to unlocking the potential of synthetic cells as cell models and as microdevices in biotechnology. However, a technological bottleneck exists preventing the creation of synthetic cells with a defined nucleus-like compartment capable of genetically programmed intercompartment signaling events. Here, we present an approach for creating synthetic cells with distinct nucleus-like compartments that can encapsulate different biochemical mixtures in discrete compartments. Our system enables in situ protein expression of membrane proteins, enabling autonomous chemical communication between nuclear and cytoplasmic compartments, leading to downstream activation of enzymatic pathways within the cell.

We report the rapid fabrication of a handheld laser cut platform that can support the assembly, functionalisation, size-control and electrical characterisation of lipid bilayers. We achieve this by building a modular DIY platform that can support the lowering of a Ag/AgCl electrode through a phase transfer column consisting of an upper oil phase containing lipids, and a lower aqueous phase containing buffer.

Soft-matter nanoscale assemblies such as liposomes and lipid nanoparticles have the potential to deliver and release multiple cargos in an externally stimulated and site-specific manner. Such assemblies are currently structurally simplistic, comprising spherical capsules or lipid clusters. Given that form and function are intertwined, this lack of architectural complexity restricts the development of more sophisticated properties. To address this, we have devised an engineering strategy combining microfluidics and conjugation chemistry to synthesize nanosized liposomes with two discrete compartments, one within another, which we term concentrisomes. We can control the composition of each bilayer and tune both particle size and the dimensions between inner and outer membranes. We can specify the identity of encapsulated cargo within each compartment, and the biophysical features of inner and outer bilayers, allowing us to imbue each bilayer with different stimuli-responsive properties. We use these particles for multi-stage release of two payloads at defined time points, and as attolitre reactors for triggered in situ biochemical synthesis.