Curated Optogenetic Publication Database

Abstract: Most membrane and secreted proteins are transported from the endoplasmic reticulum (ER) to the Golgi apparatus and subsequently directed to their final destinations in the cell. However, the mechanisms underlying transport and cargo sorting remain unclear. Recent advancements in optical microscopy, combined with synchronized cargo protein release methods, have enabled the direct observation of cargo protein transport. We developed a new optically synchronized cargo release method called retention using the dark state of LOV2 (RudLOV). This innovative technique offers three exceptional control capabilities: spatial, temporal, and quantitative control of cargo release. RudLOV uses illumination to trigger transport and detect cargo. Consequently, the selection of an appropriate laser and filter set for controlling the illumination and/or detection is crucial. The protocol presented here provides step-by-step guidelines for obtaining high-resolution live imaging data using RudLOV, thereby enabling researchers to investigate intracellular cargo transport with unprecedented precision and control. Key features • RudLOV is a new optically synchronized intracellular cargo transport method. • RudLOV enables precise spatial, temporal, and quantitative control of cargo release. • RudLOV allows cargo to be released using a 445 or 488 nm laser with less damage than UV. • RudLOV allows you to hook and release cargo without the use of exogenous chemicals.

Abstract: The response of cell populations to external stimuli plays a central role in biological mechanical processes such as epithelial wound healing and developmental morphogenesis. Wave-like propagation of a signal of ERK MAP kinase has been shown to direct collective migration in one direction; however, the mechanism based on continuum mechanics under a traveling wave is not fully understood. To elucidate how the traveling wave of the ERK kinase signal directs collective migration, we constructed the mechanical model of the epithelial cell monolayer by considering the signal-dependent coordination of contractile stress and cellular orientation. The proposed model was studied by using an optogenetically controlled cell system where we found that local signal activation induces changes in cell density and orientation with the direction of propagation. The net motion of the cell population occurred relative to the wave, and the migration velocity showed a maximum in resonance with the velocity of the ERK signal wave. The presented mechanical model was further validated in an in vitro wound healing process.

Abstract: The proper establishment of cell form, fate, and function during morphogenesis requires precise coordination between cell polarity and developmental cues. To achieve this, cells must establish polarity domains that are stable yet sensitive to guiding cues. Here we show that C. elegans germline blastomeres resolve this trade-off by creating a time-varying polarization landscape. Specifically, coupling the PAR polarity network to the cell-cycle kinase CDK-1 ensures that newborn cells operate in a low-feedback regime that lowers barriers to polarity state switching, allowing spatial cues to induce and orient PAR protein asymmetries. As CDK-1 activity rises at mitotic entry, increasing molecular feedback reinforces cue-induced asymmetries to yield robust and stable patterning of PAR domains. Consistent with this model, optogenetic and chemical perturbations show that low-CDK/low-feedback regimes destabilize PAR domains but are required for both de novo polarization and the reorientation of polarity in response to inductive cues. We propose that mitotic oscillations in cell polarity circuits dynamically optimize the polarization landscape to enable coordination of polarity with morphogenesis. Such temporal control of developmental networks is likely a general mechanism to balance robustness of cellular states with sensitivity to signal-induced state switching.

Abstract: Since its discovery, the cyclic GMP-AMP synthase (cGAS)-stimulator of the interferon gene (STING) signaling pathway has been considered a pivotal component of innate immunity and a promising target for cancer immunotherapy. Beyond its canonical role in pathogen defense, accumulating evidence has demonstrated that the cGAS-STING pathway critically regulates diverse cellular processes, including cellular senescence, autophagy, cell death, and tumor immunosurveillance; therefore, dysregulation of this pathway correlates with the pathogenesis and progression of various human diseases, ranging from autoimmune and inflammatory disorders to cancer. Herein, we reviewed the regulatory mechanisms and cellular functions of the cGAS-STING pathway, highlighting its essential role in maintaining immune homeostasis. We systematically discussed the dual roles of the cGAS-STING pathway in cancer immunity, in which it triggers both antitumor and immunosuppressive effects. Finally, we summarized the recent advances and challenges in therapeutic strategies targeting the cGAS-STING pathway and discussed the next generation of therapies, including nanomaterials, antibody-drug conjugates, engineered bacteria, alternative strategies, optogenetic approaches, and combination strategies. We hope that our efforts will advance the understanding of the fundamental principles of innate immune recognition and response, and provide novel directions for improving the clinical outcomes of cGAS-STING-targeted therapies.

Abstract: Phospholipase C-γ1 (PLC-γ1) signaling is required for mesenchymal chemotaxis, but is it sufficient to bias motility? PLC-γ1 enzyme activity is basally autoinhibited, and light-controlled membrane recruitment of wild-type (WT) PLC-γ1 (OptoPLC-γ1) in Plcg1-null fibroblasts does not trigger lipid hydrolysis, complicating efforts to isolate its contribution. Utilizing cancer-associated mutations to investigate the regulatory logic of PLC-γ1, we demonstrate that the canonical hallmark of enzyme activity, phosphorylated Tyr783 (pTyr783), is not a proxy for activity level, but is rather a marker of dysregulated autoinhibition. Accordingly, OptoPLC-γ1 with a deregulating mutation (P867R, S345F, or D1165H) exhibits elevated phosphorylation, and membrane localization of such is sufficient to activate substrate hydrolysis and concomitant motility responses. In particular, local recruitment of OptoPLC-γ1 S345F polarizes cell motility on demand. This response is spatially dose-sensitive and only partially reduced by blocking canonical PLC-γ1 signaling yet is lipase-dependent. Our findings reframe the interpretation of PLC-γ1 regulation and demonstrate that local activation of PLC-γ1 is sufficient to direct cell motility.

Abstract: Optogenetics, a modern tool to control cellular excitability in a non-invasive way, has widely been used in neuroscience. Recently, optogenetic approaches begin to be applied to studies of other biological phenomena including muscle functions. For these analyses, chicken embryos serve as an excellent model animal since they are highly amenable to site-specific manipulations with genes of optogenetics such as Channelrhodopsins, and its following targeted light irradiation. We here overview recent progresses in optogenetics using chicken embryos with a highlight on the studies of axon pathfinding, gut peristalsis, and feather morphogenesis.

Abstract: In adherent cells, actomyosin contractility is regulated mainly by the RhoA signaling pathway, which can be controlled by optogenetics. To model the mechanochemical coupling in such systems, we introduce a finite element framework based on the discontinuous Galerkin method, which allows us to treat cell doublets, chains of cells, and monolayers within the same conceptual framework. While the adherent cell layer is modeled as an actively contracting viscoelastic solid on an elastic foundation, different models are considered for the Rho pathway, starting with a simple linear chain that can be solved analytically and later including direct feedback that can be solved only numerically. Our model predicts signal propagation as a function of coupling strength and viscoelastic timescales and identifies the conditions for optimal cell responses and wave propagation. In general, it provides a systematic understanding of how biochemistry and mechanics simultaneously contribute to the communication of adherent cells.

Abstract: Recent advances in protein structure prediction by artificial intelligence have enabled the rational design of engineered enzymes with enhanced activity and precise regulatory features. Here, we report the AlphaFold3-guided enhancement of MagMboI, a photoactivatable restriction enzyme designed for light-controlled top-down genome engineering. MagMboI is derived from the type II restriction enzyme MboI and functions through a split-protein strategy in which its N- and C-terminal fragments are fused to light-inducible dimerization modules. Upon exposure to blue light, these domains heterodimerize, restoring nuclease activity in a controlled manner. Using AlphaFold3, we modeled the structure of the MagMboI-DNA complex and gained structural insights into the interaction between MagMboI and its target DNA recognition sequence (5'-GATC-3') required for Mg2+-dependent DNA cleavage. Comparing neighboring split-site variants, we identified an alternative split that increases the MagMboI-DNA interface area and enhances complex stability relative to the original construct. This redesigned variant (designated MagMboI-plus) preserves α-helical integrity while strengthening protein-DNA contacts. Although MagMboI-plus, when introduced in Saccharomyces cerevisiae cells, exhibited slightly increased DNA-cleavage activity in vivo upon blue light activation, it was found to induce more pronounced genomic rearrangements compared to the original MagMboI construct. These findings demonstrate that AlphaFold3-based prediction can accelerate functional improvements in engineered enzymes, providing a strategy for developing light-controlled genome engineering tools.

Abstract: Macrophage-based adoptive cell therapies hold promise for solid tumors, but spatiotemporally controlling macrophage polarization within the immunosuppressive tumor microenvironment remains challenging. Here, we aimed to validate an optogenetic strategy using the LOV2-STIM1 system to achieve light-induced, sustained M1 polarization of macrophages. Upon blue light stimulation, engineered macrophages robustly exhibited M1 phenotypes, suppressed melanoma cell proliferation, migration, and invasion in vitro, and recapitulated the antitumor functions of M1 macrophages. Notably, combining light-activated engineered macrophages with temozolomide in melanoma models resulted in synergistic inhibition of tumor growth. This synergy is accompanied by a profound remodeling of the tumor immune microenvironment, characterized by M1-driven reversal of chemoresistance and enhanced infiltration of cytotoxic CD8+ T cells. Our findings establish a proof-of-concept for optogenetic regulation of macrophage polarization and demonstrate its feasibility for enhancing antitumor effects and chemosensitivity in melanoma models, providing a promising and controllable platform for macrophage-based immunotherapy.

Abstract: Dynamic regulation of cell-cell adhesion is fundamental to numerous biological processes and is the key to engineering multicellular structures. Optogenetic tools offer precise spatiotemporal control over cell-cell adhesions, but current methods often require the genetic modification of each participating cell type. To address this limitation, we engineered a single-component synthetic cell adhesion molecule based on the blue-light-responsive, plasma membrane-binding protein BcLOV4. We tagged BcLOV4 with a transmembrane domain to display it on the outer plasma membrane (BcLOV4-PM). Under blue light but not in the dark, BcLOV4-PM cells formed both homotypic adhesions with other BcLOV4-PM cells and heterotypic adhesions with a range of unmodified wild-type cells. While these adhesions were not reversed in the dark, they could be efficiently disrupted by increasing the temperature to 37 °C, leveraging BcLOV4's thermosensitivity. Using BcLOV4-PM-based adhesions, we demonstrated light-controlled compaction of spheroids in both monocultures and cocultures with wild-type cells. Altogether, BcLOV4-PM enables promiscuous, modular, light-dependent control of cell-cell adhesions without requiring genetic modification of all cell types involved, offering promising applications in tissue engineering and the study of multicellular process.

Abstract: T-cell activation is a highly regulated process requiring both antigen recognition via the T-cell receptor (TCR) and co-stimulatory signaling, notably through the co-stimulatory receptor CD28. Here, we introduce an optogenetic platform for reversible and tunable full activation of human T cells that does not require genetic modification. We engineered opto-CD28-REACT, a recombinant protein comprising an anti-CD28 single-chain variable fragment, GFP, and phytochrome-interacting factor 6 (PIF6). This construct binds CD28 and thereby attaches PIF6 to CD28. Upon red light (630 nm) illumination, PIF6 binds to PhyB tetramer-coated beads, triggering CD28 signaling that can be attenuated by far-red light (780 nm) in 2 min. We show that opto-CD28-REACT synergizes with opto-CD3ϵ-REACT-a complementary optogenetic tool targeting the TCR complex-to induce light-dependent activation of both Jurkat cells and primary human T cells. Co-stimulation through both opto-REACT systems promotes ERK phosphorylation, upregulation of the activation markers CD69 and CD25, interleukin-2 (IL-2) secretion, and T-cell proliferation, reaching levels similar to conventional antibody-mediated stimulation. This strategy enables precise optical control over TCR and CD28 signaling in non-genetically modified T cells, offering a powerful approach for dissecting the regulatory dynamics of T-cell activation and advancing applications in synthetic immunology.

Abstract: Cancer cell invasion relies on dynamic cell shape changes, which originate from protrusive and contractile intracellular forces. Previous studies revealed that contractile forces are controlled by positive-feedback amplification of the contraction regulator Rho by Lbc GEFs. These GEFs were previously linked to tumor progression; however, the underlying mechanisms are poorly understood. Here, we generated a mouse melanoma model in which cytosolic levels of the Lbc GEF GEF-H1 are controlled by light. Using this model, we found that increased GEF-H1 levels strongly stimulate cell contraction dynamics. Interestingly, increased contraction dynamics rapidly induced expansion of tumor spheroids via a focal adhesion kinase-dependent mechanism. Furthermore, long-term stimulation led to the escape of individual cells from spheroids. These findings reveal new insights into the oncogenic roles of Lbc GEFs and how they might promote tumor cell invasion. We propose a mechanism in which increased cell contraction dynamics result in asymmetric pulling forces at the tumor border, promoting the detachment and escape of individual cells.

Abstract: Light-responsive proteins are involved in a wide range of essential physiological processes in bacteria, plants, and animals. Engineered light-responsive proteins have also emerged as prospective tools in biotechnology and biomedicine. These proteins are often characterized by short-lived lit states and the need for continuous illumination to reach photostationary states. Therefore, developing methods for studying light-responsive proteins and their interactions under illumination represents an important research goal. Here, we report on a novel front-illuminated surface plasmon resonance (fiSPR) biosensor for monitoring interactions involving light-responsive proteins. The fiSPR biosensor combines the optical platform based on the Kretschmann geometry with advanced transparent microfluidics and an additional light module, enabling in situ illumination of the liquid sample in contact with the SPR chip. We apply the fiSPR biosensor to study the blue light-responsive transcription factor EL222, which recovers to the dark state in a few seconds and plays an important role in the optogenetic control of gene expression. Specifically, we determine the rate and equilibrium constants for EL222 dimerization and DNA binding. The results support the hypothesis that EL222 dimerizes prior to binding DNA. In addition, we provide evidence of the interaction between an interleukin receptor modified with a photocaged tyrosine (IL-20R2-Y70NBY) and its cytokine ligand (IL-24) only upon UV illumination. Overall, this study demonstrates the versatility of the developed fiSPR biosensor for monitoring biomolecular interactions involving both natural and engineered light-responsive proteins, particularly those featuring short lit-state lifetimes.

Abstract: Precise control of covalent protein binding and cleavage in mammalian cells is crucial for manipulating cellular processes but remains challenging due to dark background, poor stability, low efficiency, or requirement of unnatural amino acids in current optogenetic tools. We introduce a photoswitchable intein (PS Intein) engineered by allosterically modulating a small autocatalytic gp41-1 intein with tandem Vivid photoreceptor. PS Intein exhibits superior functionality and low background in cells compared to existing tools. PS Intein-based systems enable light-induced covalent binding, cleavage, and release of proteins for regulating gene expression and cell fate. The high responsiveness and ability to integrate multiple inputs allow for intersectional cell targeting using cancer- and tumor microenvironment-specific promoters. PS Intein tolerates various fusions and insertions, facilitating its application in diverse cellular contexts. This versatile technology offers efficient light-controlled protein manipulation, providing a powerful tool for adding functionalities to proteins and precisely controlling protein networks in living cells.

Abstract: Cellular immunotherapy has transformed cancer treatment by harnessing T cells to target malignant cells. However, its broader adoption is hindered by challenges such as efficacy loss, limited persistence, tumor heterogeneity, an immunosuppressive tumor microenvironment (TME), and safety concerns related to systemic adverse effects. Optogenetics, a technology that uses light-sensitive proteins to regulate cellular functions with high spatial and temporal accuracy, offers a potential solution to overcome these issues. By enabling targeted modulation of T cell receptor signaling, ion channels, transcriptional programming, and antigen recognition, optogenetics provides dynamic control over T cell activation, cytokine production, and cytotoxic responses. Moreover, optogenetic strategies can be applied to remodel the TME by selectively activating immune responses or inducing targeted immune cell depletion, thereby enhancing T cell infiltration and immune surveillance. However, practical hurdles such as limited tissue penetration of visible light and the need for cell- or tissue-specific gene delivery must be addressed for clinical translation. Emerging solutions, including upconversion nanoparticles, are being explored to improve light delivery to deeper tissues. Future integration of optogenetics with existing immunotherapies, such as checkpoint blockade and adoptive T cell therapies, could improve treatment specificity, minimize adverse effects, and provide real-time control over immune responses. By refining the precision and adaptability of immunotherapy, optogenetics promises to further enhance both the safety and efficacy of cancer immunotherapy.

Abstract: In cell biology, optical techniques are increasingly used to measure cells' internal states (biosensors) and to stimulate cellular responses (optogenetics). Yet the design of all-optical experiments is often manual: a pre-determined stimulus pattern is applied to cells, biosensors are measured over time, and the resulting data is processed off-line. With the advent of machine learning for segmentation and tracking, it becomes possible to envision closed-loop experiments where real-time information about cells' positions and states are used to dynamically determine optogenetic stimuli to alter or control their behavior. Here, we develop PyCLM, a Python-based suite of tools to enable real-time measurement, image segmentation, and optogenetic control of thousands of cells per experiment. PyCLM is designed to be as simple for the end user as possible, and multipoint experiments can be set up that combine a wide variety of imaging, image processing, and stimulation modalities without any programming. We showcase PyCLM on diverse applications: studying the effect of epidermal growth factor receptor activity waves on epithelial tissue movement, simultaneously stimulating ~1,000 single cells to guide tissue flows, and performing real-time feedback control of cell-to-cell fluorescence heterogeneity. This tool will enable the next generation of dynamic experiments to probe cell and tissue properties, and provides a first step toward precise control of cell states at the tissue scale.

Abstract: Over the past two decades, optogenetics has evolved from a conceptual framework into a powerful and versatile technology for controlling cellular processes with light. Rooted in the discovery and characterization of natural photoreceptors, the field has advanced through the development of genetically encoded, light-sensitive proteins that enable precise spatiotemporal control of ion flux, intracellular signaling, gene expression, and protein interactions. This review traces key milestones in the emergence of optogenetics and highlights the development of major optogenetic tools. From the perspective of genetic tool innovation, the focus is on how these tools have been engineered and optimized for novel or enhanced functions, altered spectral properties, improved light sensitivity, subcellular targeting, and beyond. Their broadening applications are also explored across neuroscience, cardiovascular biology, hematology, plant sciences, and other emerging fields. In addition, current trends such as all-optical approaches, multiplexed control, and clinical translation, particularly in vision restoration are discussed. Finally, ongoing challenges are addressed and outline future directions in optogenetic tool development and in vivo applications, positioning optogenetics as a transformative platform for basic research and therapeutic advancement.

Abstract: Fluorescent molecules are essential for bioimaging and visualizing cellular localization, functionalities, including biosensing, ion sensing, and photochromism. The photocleavable fluorescent protein PhoCl1 belongs to a sub-class of green-to-red photoconvertible β-barrel fluorescent protein and has a characteristic green fluorescence conferred by the chromophore p-HBI. In contrast to other photoconvertible proteins, that shift their fluorescence from green-to-red upon photoexposure, PhoCl1 has been reported to render itself non-fluorescent by releasing the 9 amino-acid C-terminal peptide fragment (CTPF) bearing the photo-transformed red chromophore from the β-barrel. Here we show the fate of photoreleased chromophore which shows an unexpected dim red fluorescence. We attribute this dim red fluorescence to the aggregation of CTPF molecules which is validated through dynamic light scattering measurements. We further characterize the aggregated CTPF through various optical techniques to determine the excitation/emission maxima, fluorescence lifetime, quantum yield and rotational correlation time through fluorescence anisotropy. We assessed the red fluorescence behavior under diverse environmental conditions including variations in pH, NaCl, and temperature. Molecular dynamics simulations support our experimentally observed aggregation of CTPF molecules. We supplemented these studies with quantum mechanics/molecular mechanics study which indicated the role of the chromophore in the photodissociated peptide fragment in the generation of dim red fluorescence. These findings not only provide insight into the behavior of fluorescent chromophore-peptide conjugate but also potentially lay the groundwork for developing light-activated fluorescence systems, AIE-based biosensors, and tunable biomaterials for protein tagging and responsive material design.

Abstract: Localized translation broadly enables spatiotemporal control of gene expression. Here, we present LOV-domain-controlled ligase for translation localization (LOCL-TL), an optogenetic approach for monitoring translation with codon resolution at any defined subcellular location under physiological conditions. Application of LOCL-TL to mitochondrially localized translation revealed that ∼20% of human nuclear-encoded mitochondrial genes are translated on the outer mitochondrial membrane (OMM). Mitochondrially translated messages form two classes distinguished by encoded protein length, recruitment mechanism, and cellular function. An evolutionarily ancient mechanism allows nascent chains to drive cotranslational recruitment of long proteins via an unanticipated bipartite targeting signal. Conversely, mRNAs of short proteins, especially eukaryotic-origin electron transport chain (ETC) components, are specifically recruited by the OMM protein A-kinase anchoring protein 1 (AKAP1) in a translation-independent manner that depends on mRNA splicing. AKAP1 loss lowers ETC levels. LOCL-TL thus reveals a hierarchical strategy that enables preferential translation of a subset of proteins on the OMM.

Abstract: The actin cytoskeleton forms a meshwork that drives cellular deformation. Network properties, determined by density and actin-binding proteins, are crucial, yet how density governs protein penetration and dynamics remains unclear. Here, we report an in vitro optogenetic system, named OptoVCA, enabling Arp2/3 complex-mediated actin assembly on lipid membranes. By tuning illumination power, duration, and pattern, OptoVCA flexibly manipulates the density, thickness, and shape of the actin network. Taking these advantages, we examine how network density affects two actin-binding proteins: myosin and ADF/cofilin. We find that even modest increases in density strictly inhibit myosin filament penetration by steric hindrance. Penetrated myosin filaments generate directional actin flow in networks with density gradients. In contrast, ADF/cofilin accesses networks regardless of density, yet network disassembly is markedly reduced by increased density. Thus, OptoVCA reveals that network density differentially regulates actin-binding protein penetration and activity. These findings advance understanding of cell mechanics through precise, light-based manipulation of cytoskeletal structure.

Abstract: Morphogen gradients provide the patterning cues that instruct cell fate decisions during development. Here, we establish an optogenetic system for the precise spatiotemporal control in vitro of Sonic hedgehog (Shh) morphogen production. Using a tunable light-inducible gene expression system, we generate long-range Shh gradients that pattern mouse neural progenitors into spatially distinct domains, mimicking neural tube development. We investigate how biochemical features of Shh and Shh-interacting proteins affect patterning length scales. By measuring clearance rates, we determine that Shh has an extracellular half-life below 1.5 h, substantially shorter than downstream gene expression dynamics, indicating gradients are continually renewed during patterning. We provide evidence that progenitor identity acquisition and maintenance depend on both Shh concentration and exposure duration. Together, this approach provides a quantitative framework for investigating morphogen patterning, enabling reproducible control of morphogen dynamics to dissect the interplay between biochemical cues, gradient formation biophysics, and transcriptional programs underlying developmental patterning.

Abstract: During development, epithelia function as malleable sheets that undergo extensive remodeling to shape developing embryos. Optogenetic control of Rho signaling provides an avenue to investigate mechanisms of epithelial morphogenesis, but transgenic optogenetic tools can be limited by variability in expression levels and deleterious effects of transgenic overexpression on development. Here, we use CRISPR/Cas9 to tag Drosophila RhoGEF2 and Cysts/Dp114RhoGEF with components of the iLID/SspB optogenetic heterodimer, permitting light-dependent control over endogenous protein activities. Using quantitative optogenetic perturbations, we uncover a dose-dependence of tissue furrow depth and bending behavior on RhoGEF recruitment, revealing mechanisms by which developing embryos can shape tissues into particular morphologies. We show that at the onset of gastrulation, furrows formed by cell lateral contraction are oriented and size-constrained by basal actomyosin. Our findings demonstrate the use of quantitative, 3D-patterned perturbations of cell contractility to precisely shape tissue structures and interrogate developmental mechanics.

Abstract: Oncolytic virus (OVs) therapy has emerged as a promising modality in cancer immunotherapy, attracting growing attention for its multifaceted mechanisms of tumor elimination. However, its efficacy as a monotherapy remains constrained by physiological barriers, limited delivery routes, and suboptimal immune activation. Phototherapy, an innovative and rapidly advancing cancer treatment technology, can mitigate these limitations when used in conjunction with OVs, enhancing viral delivery, amplifying tumor destruction, and boosting antitumor immune responses. This review provides the first comprehensive analysis of synergistic integration of OVs with both photodynamic therapy (PDT) and photothermal therapy (PTT). It also explores their applications in optical imaging-guided diagnosis and optogenetically controlled delivery. Furthermore, it discusses emerging strategies involving biomimetic virus or viroid-based vectors in conjunction with phototherapy, and delves into the immunomodulatory mechanisms of this combinatorial approach. While promising in preclinical models, these combined strategies are still largely in early-stage research. Challenges such as limited light penetration, delivery efficiency, and safety concerns remain to be addressed for clinical translation. Consequently, the integration of OV therapy and phototherapy represents a compelling strategy in cancer treatment, offering significant promise for advancing precision oncology and next-generation immunotherapies.

Abstract: Organ-on-a-chip platforms have emerged as promising human tissue models for drug screening and mechanistic studies, offering alternatives to traditional animal models. Integration of vascular structures into these platforms is pivotal for creating physiologically faithful models of individual organs and studying interorgan crosstalk. However, most vascular structures grown in vitro do not account for organ-specific endothelial permeability or its modulation in response to disease. Here, we present optoBarrier, an optogenetic organ-on-a-chip platform designed to modulate endothelial barrier permeability through light stimulation. By optically activating RhoA signaling in engineered optogenetic endothelial cells, we demonstrate the formation of stress fibers, disruption of vascular endothelial cadherin (VE-cadherin) and increased barrier permeability. We further show that permeability is tunable in a reversible and dose-dependent manner in response to light. We therefore propose that optoBarrier offers a user-defined, controlled and simple method to manipulate endothelial permeability for in vitro studies of human vasculature.

Abstract: The Cre-loxP recombination system enables precise genome engineering; however, existing photoactivatable Cre tools suffer from several limitations, including low DNA recombination efficiency, background activation, slow activation kinetics, and poor tissue penetration. Here, we present REDMAPCre, a red-light-controlled split-Cre system based on the ΔPhyA/FHY1 interaction. REDMAPCre enables rapid activation (1-s illumination) and achieves an 85-fold increase in reporter expression over background levels. We demonstrate its efficient regulation of DNA recombination in mammalian cells and mice, as well as its compatibility with other inducible recombinase systems for Boolean logic-gated DNA recombination. Using a single-vector adeno-associated virus delivery system, we successfully induced REDMAPCre-mediated DNA recombination in mice. Furthermore, we generated a REDMAPCre transgenic mouse line and validated its efficient, light-dependent recombination across multiple organs. To explore its functional applications, REDMAPCre transgenic mice were crossed with isogenic Cre-dependent reporter mice, enabling optogenetic induction of insulin resistance and hepatic lipid accumulation via Cre-dependent overexpression of ubiquitin-like with PHD and RING finger domains 1 (UHRF1), as well as targeted cell ablation through diphtheria toxin fragment A expression. Collectively, REDMAPCre provides a powerful tool for achieving remote control of recombination and facilitating functional genetic studies in living systems.