Curated Optogenetic Publication Database

Abstract: Intracellular optogenetics represents a rapidly advancing biotechnology that enables precise, reversible control of protein activity, signaling dynamics, and cellular behaviours using genetically encoded, light-responsive systems. Originally pioneered in neuroscience through channelrhodopsins to manipulate neuronal excitability, the field has since expanded into diverse intracellular applications with broad implications for medicine, agriculture, and biomanufacturing. Key to these advances are photoreceptors such as cryptochrome 2 (CRY2), light-oxygen-voltage (LOV) domains, and phytochromes, which undergo conformational changes upon illumination to trigger conditional protein-protein interactions, localization shifts, or phase transitions. Recent engineering breakthroughs-including the creation of red-light responsive systems such as MagRed that exploit endogenous biliverdin-have enhanced tissue penetration, minimized phototoxicity, and expanded applicability to complex biological systems. This review provides an overarching synthesis of the molecular principles underlying intracellular optogenetic actuators, including the photophysical basis of light-induced conformational changes, oligomerization, and signaling control. We highlight strategies that employ domain fusions, rational mutagenesis, and synthetic circuits to extend their utility across biological and industrial contexts. We also critically assess current limitations, such as chromophore dependence, light delivery challenges, and safety considerations, so as to frame realistic paths towards translation. Looking ahead, future opportunities include multi-colour and multiplexed systems, integration with high-throughput omics and artificial intelligence, and development of non-invasive modalities suited for in vivo and industrial applications. Intracellular optogenetics is thus emerging as a versatile platform technology, with the potential to reshape how we interrogate biology and engineer cells for therapeutic, agricultural, and environmental solutions.

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: 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: Optogenetically regulated enzymes offer unprecedented spatiotemporal control over protein activity, intermolecular interactions, and intracellular signaling. Many design strategies have been developed for their fabrication based on the principles of intrinsic allostery, oligomerization or 'split' status, intracellular compartmentalization, and steric hindrance. In addition to employing photosensory domains as part of the traditional optogenetic toolset, the specificity of effector domains has also been leveraged for endogenous applications. Here, we discuss the dynamics of light activation while providing a bird's eye view of the crafting approaches, targets, and impact of optogenetic enzymes in orchestrating cellular functions, as well as the bottlenecks and an outlook into the future.

Abstract: Neurodegenerative diseases involve toxic protein aggregation. Recent evidence suggests that biomolecular phase separation, a process in which proteins and nucleic acids form dynamic, liquid-like condensates, plays a key role in this aggregation. Optogenetics, originally developed to control neuronal activity with light, has emerged as a powerful tool to investigate phase separation in living systems. This is achieved by fusing disease-associated proteins to light-sensitive oligomerization domains, enabling researchers to induce or reverse condensate formation with precise spatial and temporal control. This review highlights how optogenetic systems such as OptoDroplet are being used to dissect the mechanisms of neurodegenerative disease. We examine how these tools have been applied in models of neurodegenerative diseases, such as amyotrophic lateral sclerosis, Alzheimer's, Parkinson's, and Huntington's disease. These studies implicate small oligomeric aggregates as key drivers of toxicity and highlight new opportunities for therapeutic screening. Finally, we discuss advances in light-controlled dissolution of condensates and future directions for applying optogenetics to combat neurodegeneration. By enabling precise, dynamic control of protein phase behavior in living systems, optogenetic approaches provide a powerful framework for elucidating disease mechanisms and informing the development of targeted therapies.

Abstract: Adrenoceptors (ARs) play a vital role in various physiological processes and are key therapeutic targets. The advent of optical control techniques, including optogenetics and photopharmacology, offers the potential to modulate AR signaling with precise temporal and spatial resolution. In this review, we summarize the latest advancements in the optical control of AR signaling, encompassing optogenetics, photocaged compounds, and photoswitchable compounds. We also discuss the limitations of current tools and provide an outlook on the next generation of optogenetic and photopharmacological tools. These emerging optical technologies not only enhance our understanding of AR signaling but also pave the way for potential therapeutic developments.

Abstract: Ferroptosis is a lytic, iron-dependent form of regulated cell death characterized by excessive lipid peroxidation and associated with necrosis spread in diseased tissues through unknown mechanisms. Using a novel optogenetic system for light-driven ferroptosis induction via degradation of the anti-ferroptotic protein GPX4, we show that lipid peroxidation and ferroptotic death can spread to neighboring cells through their closely adjacent plasma membranes. Ferroptosis propagation is dependent on cell distance and completely abolished by disruption of α-catenin-dependent intercellular contacts or by chelation of extracellular iron. Remarkably, bridging cells with a lipid bilayer or increasing contacts between neighboring cells enhances ferroptosis spread. Reconstitution of iron-dependent spread of lipid peroxidation between pure lipid, contacting liposomes provides evidence for the physicochemical mechanism involved. Our findings support a model in which iron-dependent lipid peroxidation propagates across proximal plasma membranes of neighboring cells, thereby promoting the transmission of ferroptotic cell death with consequences for pathological tissue necrosis spread.

Abstract: Elongation of the vertebrate embryonic axis necessitates rapid expansion of the epidermis to accommodate the growth of underlying tissues. Here, we generated a toolkit to visualize and quantify signaling in entire cell populations of the periderm, the outermost layer of the epidermis, in live developing zebrafish. We find that oriented cell divisions facilitate growth of the early periderm during axial elongation rather than cell addition from the basal layer. Activity levels of Extracellular signal-regulated kinase (ERK), a downstream effector of the MAPK pathway, gauged by a live biosensor, predict cell cycle entry, and optogenetic ERK activation regulates cell cycling dynamics. As development proceeds, rates of peridermal cell proliferation decrease, and ERK activity becomes more pulsatile and functionally transitions to promote hypertrophic cell growth. Targeted genetic blockade of cell division generates animals with oversized periderm cells, yet, unexpectedly, development to adulthood is not impaired. Our findings reveal stage-dependent differential responsiveness to ERK signaling and marked developmental robustness in growing teleost skin.

Abstract: The binding of photoswitchable molecules to partners forms the basis of many naturally occurring light-dependent signaling pathways and various photopharmacological and optogenetic tools. A critical parameter affecting the function of these molecules is the thermal half-life of the light state. Reports in the literature indicate that, in some cases, a binding partner can significantly influence the thermal half-life, while in other cases it has no effect. Here, we present a unifying framework for quantitatively analyzing the effects of binding partners on thermal reversion rates. We focus on photoswitchable protein/binder interactions involving LOV domains, photoactive yellow protein, and CBCR GAF domains with partners that bind either the light or the dark state of the photoswitchable domain. We show that the effect of a binding partner depends on the extent to which the transition state for reversion resembles the dark state or the light state. We quantify this resemblance with a ϕswitching value, where ϕswitching = 1 if the conformation of the part of the photoswitchable molecule that interacts with the binding partner closely resembles its dark state conformation and ϕswitching = 0 if it resembles its light state. In addition to providing information on the transition state for switching, this analysis can guide the design of photoswitchable systems that retain useful thermal half-lives in practice. The analysis also provides a basis for the use of simple kinetic measurements to determine effective changes in affinity even in complex milieu.

Abstract: Optogenetics has substantially enhanced our understanding of biological processes by enabling high-precision tracking and manipulation of individual cells. It relies on photosensitive proteins to monitor and control cellular activities, thereby paving the way for significant advancements in complex system research. Photosensitive proteins play a vital role in the development of optogenetics, facilitating the establishment of cutting-edge methods. Recent breakthroughs in protein design have opened up opportunities to develop protein-based tools that can precisely manipulate and monitor cellular activities. These advancements will significantly accelerate the development and application of optogenetic tools. This article emphasizes the pivotal role of protein design in the development of optogenetic tools, offering insights into potential future directions. We begin by providing an introduction to the historical development and fundamental principles of optogenetics, followed by an exploration of the operational mechanisms of key photosensitive domains, which includes clarifying the conformational changes they undergo in response to light, such as allosteric modulation and dimerization processes. Building on this foundation, we reveal the development of protein design tools that will enable the creation of even more sophisticated optogenetic techniques.

Abstract: Optogenetics is an empowering technology that uses light-responsive proteins to control biological processes. Because of its genetic tractability, abundance of genetic tools, and robust culturing conditions, Saccharomyces cerevisiae has served for many years as an ideal platform in which to study, develop, and apply a wide range of optogenetic systems. In many instances, yeast has been used as a steppingstone in which to characterize and optimize optogenetic tools to later be deployed in higher eukaryotes. More recently, however, optogenetic tools have been developed and deployed in yeast specifically for biotechnological applications, including in nonconventional yeasts. In this review, we summarize various optogenetic systems responding to different wavelengths of light that have been demonstrated in diverse yeast species. We then describe various applications of these optogenetic tools in yeast, particularly in metabolic engineering and recombinant protein production. Finally, we discuss emerging applications in yeast cybergenetics-the interfacing of yeast and computers for closed-loop controls of yeast bioprocesses-and the potential impact of optogenetics in other future biotechnological applications.

Abstract: Collective cell migration and tissue morphogenesis play a variety of important roles in the development of many species. Tissue morphogenesis often generates mechanical forces that alter cell shapes and arrangements, resembling collective cell migration-like behaviors. Genetic methods have been widely used to study collective cell migration and its like behavior, advancing our understanding of these processes during development. However, a growing body of research shows that collective cell migration during development is not a simple behavior but is often combined with other cellular and tissue processes. In addition, different surrounding environments can also influence migrating cells, further complicating collective cell migration during development. Due to the complexity of developmental processes and tissues, traditional genetic approaches often encounter challenges and limitations. Thus, some methods with spatiotemporal control become urgent in dissecting collective cell migration and tissue morphogenesis during development. Optogenetics is a method that combines optics and genetics, providing a perfect strategy for spatiotemporally controlling corresponding protein activity in subcellular, cellular or tissue levels. In this review, we introduce the basic mechanisms underlying different optogenetic tools. Then, we demonstrate how optogenetic methods have been applied in vivo to dissect collective cell migration and tissue morphogenesis during development. Additionally, we describe some promising optogenetic approaches for advancing this field. Together, this review will guide and facilitate future studies of collective cell migration in vivo and tissue morphogenesis by optogenetics.

Abstract: The CRISPR/Cas9 gene-editing technology, derived from the adaptive immune mechanisms of bacteria, has demonstrated remarkable advantages in fields such as gene function research and the treatment of genetic diseases due to its simplicity in design, precise targeting, and ease of use. Despite challenges such as off-target effects and cytotoxicity, effective spatiotemporal control strategies have been achieved for the CRISPR/Cas9 system through precise regulation of Cas9 protein activity as well as engineering of guide RNAs (gRNAs). This review provides a comprehensive analysis of the core components and functional mechanisms underlying the CRISPR/Cas9 system, highlights recent advancements in spatiotemporal control strategies, and discusses future directions for development.

Abstract: As synthetic biology advances, the necessity for robust biocontainment strategies for genetically engineered organisms (GEOs) grows increasingly critical to mitigate biosafety risks related to their potential environmental release. This paper aims to evaluate environment signal-dependent biocontainment systems for engineered organisms, focusing specifically on leveraging triggered responses and combinatorial systems. There are different types of triggers—chemical, light, temperature, and pH—this review illustrates how these systems can be designed to respond to environmental signals, ensuring a higher safety profile. It also focuses on combinatorial biocontainment to avoid consequences of unintended GEO release into an external environment. Case studies are discussed to demonstrate the practical applications of these systems in real-world scenarios.

Abstract: Cells use traction forces to sense mechanical cues in their environment. While the molecular clutch model effectively explains how cells exert more forces on stiffer substrates, it falls short in addressing their adaptation to dynamic mechanical fluctuations prevalent in tissues and organs. Here, using hydrogel with photo-responsive rigidity, we show that cells' response to rigidity changes is frequency dependent. Strikingly, at certain frequencies, cellular traction forces exceed those on static substrates 4-fold stiffer, challenging the established molecular clutch model. We discover that the discrepancy between the rapid adaptation of traction forces and the slower deactivation of mechanotransduction signaling proteins results in their accumulation, thereby enhancing long-term cellular traction in dynamic settings. Consequently, we propose a new model that melds immediate mechanosensing with extended mechanical signaling. Our study underscores the significance of dynamic rigidity in the development of synthetic biomaterials, emphasizing the importance of considering both immediate and prolonged cellular responses.

Abstract: In recent decades, the field of synthetic biology has witnessed remarkable progress, driving advances in both research and practical applications. One pivotal area of development involves the design of transgene switches capable of precisely regulating specified outputs and controlling cell behaviors in response to physical cues, which encompass light, magnetic fields, temperature, mechanical forces, ultrasound, and electricity. In this review, we delve into the cutting-edge progress made in the field of physically controlled protein expression in engineered mammalian cells, exploring the diverse genetic tools and synthetic strategies available for engineering targeting cells to sense these physical cues and generate the desired outputs accordingly. We discuss the precision and efficiency limitations inherent in these tools, while also highlighting their immense potential for therapeutic applications.

Abstract: Diabetes mellitus (DM) is a common chronic disease affecting humans globally. It is characterized by abnormally elevated blood glucose levels due to the failure of insulin production or reduction of insulin sensitivity and functionality. Insulin and glucagon-like peptide (GLP)-1 replenishment or improvement of insulin resistance are the two major strategies to treat diabetes. Recently, optogenetics that uses genetically encoded light-sensitive proteins to precisely control cell functions has been regarded as a novel therapeutic strategy for diabetes. Here, we summarize the latest development of optogenetics and its integration with synthetic biology approaches to produce light-responsive cells for insulin/GLP-1 production, amelioration of insulin resistance and neuromodulation of insulin secretion. In addition, we introduce the development of cell encapsulation and delivery methods and smart bioelectronic devices for the in vivo application of optogenetics-based cell therapy in diabetes. The remaining challenges for optogenetics-based cell therapy in the clinical translational study are also discussed.

Abstract: Hydrophilic and biocompatible hydrogels are widely applied as ideal scaffolds in tissue engineering. The "smart" gelation material can alter its structural, physiochemical, and functional features in answer to various endo/exogenous stimuli to better biomimic the endogenous extracellular matrix for the engineering of cells and tissues. Light irradiation owns a high spatial-temporal resolution, complete biorthogonal reactivity, and fine-tunability and can thus induce physiochemical reactions within the matrix of photoresponsive hydrogels with good precision, efficiency, and safety. Both gel structure (e.g., geometry, porosity, and dimension) and performance (like conductivity and thermogenic or mechanical properties) can hence be programmed on-demand to yield the biochemical and biophysical signals regulating the morphology, growth, motility, and phenotype of engineered cells and tissues. Here we summarize the strategies and mechanisms for encoding light-reactivity into a hydrogel and demonstrate how fantastically such responsive gels change their structure and properties with light irradiation as desired and thus improve their applications in tissue engineering including cargo delivery, dynamic three-dimensional cell culture, and tissue repair and regeneration, aiming to provide a basis for more and better translation of photoresponsive hydrogels in the clinic.

Abstract: Optogenetic, known as the method of 21 centuries, combines optic and genetic engineering to precisely control photosensitive proteins for manipulation of a broad range of cellular functions, such as flux of ions, protein oligomerization and dissociation, cellular intercommunication, and so on. In this technique, light is conventionally delivered to targeted cells through optical fibers or micro light-emitting diodes, always suffering from high invasiveness, wide-field illumination facula, strong absorption, and scattering by nontargeted endogenous substance. Light-transducing nanomaterials with advantages of high spatiotemporal resolution, abundant wireless-excitation manners, and easy functionalization for recognition of specific cells, recently have been widely explored in the field of optogenetics; however, there remain a few challenges to restrain its clinical applications. This review summarized recent progress on light-responsive genetically encoded proteins and the myriad of activation strategies by use of light-transducing nanomaterials and their disease-treatment applications, which is expected for sparking helpful thought to push forward its preclinical and translational uses.

Abstract: Hydrogel biomaterials offer great promise for 3D cell culture and therapeutic delivery. Despite many successes, challenges persist in that gels formed from natural proteins are only marginally tunable while those derived from synthetic polymers lack intrinsic bioinstructivity. Towards the creation of biomaterials with both excellent biocompatibility and customizability, recombinant protein-based hydrogels have emerged as molecularly defined and user-programmable platforms that mimic the proteinaceous nature of the extracellular matrix. Here, we introduce PhoCoil, a dynamically tunable recombinant hydrogel formed from a single protein component with unique multi-stimuli responsiveness. Physical crosslinking through coiled-coil interactions promotes rapid shear-thinning and self-healing behavior, rendering the gel injectable, while an included photodegradable motif affords on-demand network dissolution via visible light. PhoCoil gel photodegradation can be spatiotemporally and lithographically controlled in a dose-dependent manner, through complex tissue, and without harm to encapsulated cells. We anticipate that PhoCoil will enable new applications in tissue engineering and regenerative medicine.

Abstract: Only a few short decades have passed since the sequencing of GFP, yet the modern repertoire of transgenically encoded optical tools implies an exponential proliferation of ever improving constructions to interrogate the subcellular environment. A myriad of tags for labeling proteins, RNA, or DNA have arisen in the last few decades, facilitating unprecedented visualization of subcellular components and processes. Development of a broad array of modern genetically encoded sensors allows real-time, in vivo detection of molecule levels, pH, forces, enzyme activity, and other subcellular and extracellular phenomena in ever expanding contexts. Optogenetic, genetically encoded optically controlled manipulation systems have gained traction in the biological research community and facilitate single-cell, real-time modulation of protein function in vivo in ever broadening, novel applications. While this field continues to explosively expand, references are needed to assist scientists seeking to use and improve these transgenic devices in new and exciting ways to interrogate development and disease. In this review, we endeavor to highlight the state and trajectory of the field of in vivo transgenic optical tools.

Abstract: We developed a system for optogenetic release of single molecules in cells. We confined soluble and transmembrane proteins to the Golgi apparatus via a photocleavable protein and released them by short pulses of light. Our method allows for a light dose-dependent delivery of functional proteins to the cytosol and plasma membrane in amounts compatible with single-molecule imaging, greatly simplifying access to single-molecule microscopy of any protein in live cells. We were able to reconstitute ion conductance by delivering BK and LRRC8/volume-regulated anion channels to the plasma membrane. Finally we were able to induce NF-kB signaling in T lymphoblasts stimulated by interleukin-1 by controlled release of a signaling protein that had been knocked out. We observed light-induced formation of functional inflammatory signaling complexes that triggered phosphorylation of the inhibitor of nuclear factor kappa-B kinase only in activated cells. We thus developed an optogenetic method for the reconstitution and investigation of cellular function at the single-molecule level.

Abstract: Proteases function as pivotal molecular switches, initiating numerous biological events. Notably, potyviral protease, derived from plant viruses, has emerged as a trusted proteolytic switch in synthetic biological circuits. To harness their capabilities, we have developed a single-component photocleavable switch, termed LAUNCHER (Light-Assisted UNcaging switCH for Endoproteolytic Release), by employing a circularly permutated tobacco etch virus protease and a blue-light-gated substrate, which are connected by fine-tuned intermodular linkers. As a single-component system, LAUNCHER exhibits a superior signal-to-noise ratio compared with multi-component systems, enabling precise and user-controllable release of payloads. This characteristic renders LAUNCHER highly suitable for diverse cellular applications, including transgene expression, tailored subcellular translocation and optochemogenetics. Additionally, the plug-and-play integration of LAUNCHER into existing synthetic circuits facilitates the enhancement of circuit performance. The demonstrated efficacy of LAUNCHER in improving existing circuitry underscores its significant potential for expanding its utilization in various applications.

Abstract: Cell contraction plays an important role in many physiological and pathophysiological processes. This includes functions in skeletal, heart, and smooth muscle cells, which lead to highly coordinated contractions of multicellular assemblies, and functions in non-muscle cells, which are often highly localized in subcellular regions and transient in time. While the regulatory processes that control cell contraction in muscle cells are well understood, much less is known about cell contraction in non-muscle cells. In this review, we focus on the mechanisms that control cell contraction in space and time in non-muscle cells, and how they can be investigated by light-based methods. The review particularly focusses on signal networks and cytoskeletal components that together control subcellular contraction patterns to perform functions on the level of cells and tissues, such as directional migration and multicellular rearrangements during development. Key features of light-based methods that enable highly local and fast perturbations are highlighted, and how experimental strategies can capitalize on these features to uncover causal relationships in the complex signal networks that control cell contraction.

Abstract: Alzheimer's disease (AD) is the most common form of dementia, resulting in disability and mortality. The global incidence of AD is consistently surging. Although numerous therapeutic agents with promising potential have been developed, none have successfully treated AD to date. Consequently, the pursuit of novel methodologies to address neurodegenerative processes in AD remains a paramount endeavor. A particularly promising avenue in this search is optogenetics, enabling the manipulation of neuronal activity. In recent years, research attention has pivoted from neurons to glial cells. This review aims to consider the potential of the optogenetic correction of astrocyte metabolism as a promising strategy for correcting AD-related disorders. The initial segment of the review centers on the role of astrocytes in the genesis of neurodegeneration. Astrocytes have been implicated in several pathological processes associated with AD, encompassing the clearance of β-amyloid, neuroinflammation, excitotoxicity, oxidative stress, and lipid metabolism (along with a critical role in apolipoprotein E function). The effect of astrocyte-neuronal interactions will also be scrutinized. Furthermore, the review delves into a number of studies indicating that changes in cellular calcium (Ca2+) signaling are one of the causes of neurodegeneration. The review's latter section presents insights into the application of various optogenetic tools to manipulate astrocytic function as a means to counteract neurodegenerative changes.