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1. Liquid-Liquid Phase Separation Enables Highly Selective Viral Genome Packaging

   https://doi.org/10.1103/kx13-czqb  

   Frechette, Layne B; Hagan, Michael F (February 2026, PRX Life)

   In many viruses, hundreds of proteins assemble an outer shell (capsid) around the viral nucleic acid to form an infectious virion. How the assembly process selects the viral genome amidst a vast excess of diverse cellular nucleic acids is poorly understood. It has recently been discovered that many viruses perform assembly and genome packaging within liquid-liquid phase separated biomolecular condensates inside the host cell. However, the role of condensates in genome packaging is poorly understood. Here, we construct equilibrium and dynamical rate equation models for condensate-coupled assembly and genome packaging. We show that when the viral genome and capsid proteins favorably partition into the condensate, assembly rates, yields, and packaging efficiencies can increase by orders of magnitude. Selectivity is further enhanced by the condensate when capsid proteins are translated during assembly and packaging. Our results suggest that viral condensates provide a mechanism to ensure robust and highly selective assembly of virions around viral genomes. More broadly, our results may apply to other types of selective co-assembly processes that occur within biomolecular condensates and suggest that liquid-liquid phase-separated condensates could be exploited for selective encapsulation of microscopic cargo in human-engineered systems. 

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2. Mass Spectrometry of RNA-Binding Proteins during Liquid–Liquid Phase Separation Reveals Distinct Assembly Mechanisms and Droplet Architectures

   https://doi.org/10.1021/jacs.3c00932  

   Sahin, Cagla; Motso, Aikaterini; Gu, Xinyu; Feyrer, Hannes; Lama, Dilraj; Arndt, Tina; Rising, Anna; Gese, Genis Valentin; Hällberg, B Martin; Marklund, Erik G; et al (May 2023, Journal of the American Chemical Society)

   Liquid−liquid phase separation (LLPS) of heterogeneous ribonucleoproteins (hnRNPs) drives the formation of membraneless organelles, but structural information about their assembled states is still lacking. Here, we address this challenge through a combination of protein engineering, native ion mobility mass spectrometry, and molecular dynamics simulations. We used an LLPS-compatible spider silk domain and pH changes to control the self-assembly of the hnRNPs FUS, TDP-43, and hCPEB3, which are implicated in neurodegeneration, cancer, and memory storage. By releasing the proteins inside the mass spectrometer from their native assemblies, we could monitor conformational changes associated with liquid−liquid phase separation. We find that FUS monomers undergo an unfolded-to-globular transition, whereas TDP-43 oligomerizes into partially disordered dimers and trimers. hCPEB3, on the other hand, remains fully disordered with a preference for fibrillar aggregation over LLPS. The divergent assembly mechanisms revealed by ion mobility mass spectrometry of soluble protein species that exist under LLPS conditions suggest structurally distinct complexes inside liquid droplets that may impact RNA processing and translation depending on biological context. 

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3. Boundary vortex formation in polarization-modulated orthogonal smectic liquid crystals

   https://doi.org/10.1137/19M1301618  

   Garcia-Cervera, CJ Giorgi (January 2020, SIAM journal on applied mathematics)

   null (Ed.)

   We investigate the relaxation of an energy functional that originated in the physics literature to study the bistability of polarization modulated orthogonal smectic phases SmAPFmod of bent-core molecule liquid crystals. We show that the interplay between the mixed boundary conditions and the shape of the sample results in boundary defects. We also analyze the bistable switching due to an applied electric field via gradient flow numerical simulations. Our computations reveal a novel dynamic scenario, where switching is achieved by the formation of two internal vortices. 

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4. Regulating the Growth of Cesium Lead Bromide Quantum Dots at a Liquid/Liquid Interface Constrained in a Micropipette

   https://doi.org/10.1002/smtd.202501177  

   Chandra, Sohom; Mi, Chenjia; Peng, Zongkai; Wilton, Jack; Shabgard, Hamidreza; Yang, Zhibo; Dong, Yitong (September 2025, Small Methods)

   Abstract: Colloidal all‐inorganic lead halide perovskite quantum dots (QDs) are high‐performance light‐emitting materials with size‐dependent optical properties and can be readily synthesized by mixing ionic precursors. However, the low formation energy of the perovskite lattice makes their growth too fast to control under regular reaction conditions. Diffusion‐regulated CsPbBr3 perovskite QD growth is reported on a nanometer‐sized liquid/liquid (L/L) interface supported in a micropipette tip without long‐chain organic ligands. The precursors are divided into two immiscible solutions across the L/L interface to avoid additional nucleation, and the QD growth kinetics are regulated by the constrained cationic diffusion field depending on the size of the micropipette tip. QDs with unprecedentedly small sizes (2.7 nm) are obtained due to the slowed‐down growth rates. The synthesis approach demonstrates the potential of micro‐controlled colloidal QD synthesis for mechanistic studies and micro‐fabrications. 

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5. Frequency-selective actuation of liquid crystalline elastomer actuators with radio-frequency

   https://doi.org/10.1038/s41467-025-62313-9  

   Song, Yiwen; Li, Zefang; Zadan, Mason; Wang, Jingxian; Kumar, Swarun; Majidi, Carmel (December 2025, Nature Communications)

   Abstract Soft and miniaturized robots possess the capability to operate inside narrow, confined environments. However, powering soft robots inside these environments with on-board batteries or wired connections to external power supplies can significantly restrain their mobility. Similarly, wireless actuation approaches are constrained by near-field actuation, line-of-sight operation, or indiscriminate actuation of many actuators. To provide higher mobility for wireless soft robot to operate inside non-line-of-sight scenarios, we present a radio-frequency system that introduces frequency-selective actuation of liquid crystal elastomer actuators. We create liquid crystalline elastomer actuators with a low actuation temperature and embed them with conductive traces that resonate and heat by selected frequencies of radio-frequency excitation in the 2.40 GHz range. We further develop a wireless actuation platform that infers the wireless channel and beamforms towards the actuator to achieve efficient beamforming. Demonstrations show our system is capable of selectively actuating different actuators while the robot is in motion and obstructed by occlusions. 

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