Toolkit Items

AQTrip is an engineered EL222 variant carrying V41I, L52I, A79Q, and V121I substitutions in the blue-light-responsive LOV–HTH transcription factor. It stabilizes the photoactivated state and, in the reported study, oligomerizes without DNA and forms an EL222 dimer–DNA complex in the presence of DNA substrates.

Arabidopsis cryptochrome 2 (AtCRY2) is a blue-light-responsive plant photoreceptor domain that has been heterologously expressed in mammalian cells. In that context, blue light induces AtCRY2 photobody formation and also triggers AtCRY2 degradation, providing a light-controlled module linked to protein clustering and turnover.

The Arabidopsis CRY2 photosensory domain is a light-responsive protein domain from plant cryptochrome-2 whose active-state crystal structure was determined in a tetrameric form. Structural analysis indicates that this domain undergoes photo-induced oligomerization and contains specific structural elements and residues that participate in activation.

Associating photoreceptors are light-responsive receptors defined by changes in oligomeric state as part of light-regulated allostery. In engineered systems, they provide a multi-component switch architecture based on light-controlled association behavior.

BcLOV4 is a blue-light-responsive photoreceptor domain that undergoes both clustering and plasma membrane translocation. These coupled light-induced behaviors have been harnessed as a single-component optogenetic module to control protein localization and downstream signaling.

BcLOVclust is a cytoplasmic BcLOV4-derived protein domain engineered for light-controlled intracellular clustering. It enables optogenetic clustering in mammalian cells and has been applied to control signaling proteins and stress granules.

Biofunctional nanodot arrays (bNDAs) are nanoscale surface-patterned delivery harnesses designed to spatially control dimerization and clustering of cell-surface receptors. In live cells, they were used to capture extracellularly GFP-tagged Lrp6 and drive assembly of active Wnt signalosomes at the plasma membrane.

Caenorhabditis elegans light-induced coclustering (CeLINC) is a fluorescence-based optical binary protein-protein interaction assay for testing whether two proteins interact in vivo in C. elegans. It uses light-induced coclustering as the assay readout for protein association.

The chemically inducible RTK platform is a multi-component chemical switch that enables tunable, background-minimized activation of receptor tyrosine kinases. Upon chemical induction, it drives RTK clustering at the plasma membrane and elicits ERK-dependent cellular responses while allowing activation to be intentionally triggered.

CluMPS (Clusters Magnified by Phase Separation) is a fluorescent reporter strategy for high-sensitivity detection of protein clusters in cells. It is reported to visualize submicroscopic clusters, including small aggregates, and to track clusters of unmodified, tagged, and endogenous proteins.

Clustering Indirectly using Cryptochrome 2 (CLICR) is a genetically encoded optogenetic method for spatiotemporal control of endogenous transmembrane receptor activation. It uses engineered Arabidopsis Cry2 to regulate target receptor clustering through noncovalent interactions, thereby activating downstream signaling.

The CRISPR/Cas system is a multi-component genomic engineering platform composed of clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins. It is described as a versatile and powerful genetic tool for genome manipulation, with reported applicability across essentially any organism and cell type.

The CRY2-CIB1 interaction system is a blue-light-responsive optogenetic multi-component switch built from the light-inducible CRY2-CIB1 interaction system in mammalian cells. Photoexcited CRY2 supports inducible CRY2-CIB1 heterodimerization and can also undergo concomitant CRY2-CRY2 homo-oligomerization, enabling light-controlled manipulation of signaling pathways and cellular processes with high spatiotemporal precision.

The CRY2-CRY2 interaction system is a blue-light-responsive optogenetic switch in which photoexcited cryptochrome 2 undergoes homo-oligomerization. In mammalian cells, this light-inducible interaction has been used to manipulate signaling pathways and cellular processes with high spatiotemporal precision.

The CRY2-mCherry-Drosophila β-catenin optogenetic switch is a fusion protein comprising Arabidopsis thaliana CRY2, mCherry, and Drosophila β-catenin. Blue light induces oligomerization of the fusion protein, which inhibits downstream Wnt signaling in vitro and in vivo and enables temporal inactivation of β-catenin.

CRY2/CIB1 is a blue-light-inducible multi-component interaction switch composed of the photoreceptor CRY2 and its interacting partner CIB1. It is used for acute light-dependent protein recruitment, including plasma-membrane recruitment and clustering, to control protein localization and downstream signaling with high spatial and temporal resolution.

CRY2clust is an engineered CRY2-based optogenetic module that drives blue light-dependent homo-oligomerization and clustering of fused target proteins. It was reported as a new CRY2 variant that enables rapid and efficient protein clustering with spatiotemporal optical control.

Defined oligomers of CENP-T are genetically engineered multimeric assemblies of the inner kinetochore protein CENP-T produced using two distinct systems in human cells. These higher-order CENP-T assemblies increase recruitment of outer kinetochore components and, when configured to mimic centromeric density, can induce functional cytoplasmic kinetochore-like particles.

Intrinsically disordered regions (IDRs) are protein domains used in engineered synthetic condensates to drive constitutive oligomerization and cluster formation. In the cited modular membraneless organelle design, IDR-mediated assembly is separated from cargo recruitment by fused interaction domains, enabling tunable control of condensate composition and function.

Light-activated MLKL is an engineered optogenetic MLKL system that undergoes rapid light-triggered oligomerization and plasma membrane recruitment, causing rapid cell death. A re-engineered variant blocks the cell-killing activity while retaining light-mediated membrane recruitment, enabling single-component control of protein function at the plasma membrane.

The light-controlled optogenetic CD3ζ clustering tool is a multi-component optogenetic system engineered to induce spatial clustering of CD3ζ chains with light. In the cited 2020 study, light-driven CD3ζ clustering was sufficient to initiate proximal T cell receptor signaling, including CD3ζ phosphorylation and recruitment of the tandem SH2 domain of Zap70 to plasma membrane clusters.

The light-induced co-clustering assay is an optogenetic functional assay used to assess protein-protein interactions in Drosophila S2 cells. It was reported in the context of light-induced protein clustering and uses co-clustering as the interaction readout.

Light-inducible oligomerization of Eps15 is an optogenetic engineering method used to tune Eps15 initiator-protein assembly strength in real time during endocytosis. In mammalian Eps15 knockout cells, low light produced liquid-like Eps15 assemblies that restored normal endocytic rates, whereas higher light produced solid-like assemblies that stalled vesicle budding.

Light-regulated association reactions are an engineering design principle in photoreceptor-based systems in which illumination changes protein oligomeric state as part of light-regulated allostery. A survey of engineered photoreceptors identifies this principle as particularly powerful and versatile for constructing light-responsive tools.

Multicomponent, ligand-functionalized microarrays are a patterned substrate assay method for individual living cells that spatially segregates distinct ligand presentations to enable simultaneous monitoring of receptor activation and downstream signaling. The method was developed to probe clustering-dependent EphA2 signal transduction.

Oligomerization reactions are a fundamental engineering strategy for optogenetic control of bacterial gene expression. In this context, light regulates signaling through oligomerization-based processes to drive upregulation or downregulation of expression outputs.

The oligomerizing CRY2 component is a modified CRY2-based optogenetic construct tested in Drosophila melanogaster as a tool for negative regulation of targeted proteins. The available evidence indicates that it was evaluated in the context of adapting CRY2/CIB optogenetic components to Drosophila-specific constructs.

opto-Dab1 is a single-component, photoactivatable version of Disabled-1 (Dab1) created by exploiting the blue light-sensitive dimerization/oligomerization properties of Arabidopsis thaliana Cryptochrome 2 (Cry2). Upon blue light illumination, it enables rapid, local, and reversible activation of Dab1 downstream signaling.

OptoCNK1 is an optogenetic CNK1 clustering construct implemented in MCF7 cells to stimulate CNK1 independently of upstream effectors. Light-induced CNK1 clustering was reported to selectively engage RAF-MEK-ERK or AKT signaling as a function of applied light intensity, with corresponding effects on cell fate.

OptoDroplet is an optogenetic multi-component switch that controls biomolecular phase separation by fusing disease-associated proteins to light-sensitive oligomerization domains. Light input enables induction or reversal of condensate formation with spatial and temporal control.

The optogenetic Amyloid-β2 peptide is a fluorescently tagged construct, also referred to as Aβ2-CRY2-mCherry, designed for blue-light-controlled oligomerization of an amyloid-β species in vivo. It enables inducible amyloid-β oligomerization for neurodegeneration-related studies.

Optogenetic protein clustering is a light-controlled engineering method reported in mammalian cells to induce protein clustering and activate signaling. The available evidence identifies it as an optogenetic approach for regulating signaling with light input.

The optogenetic zebrafish ALS model is an in vivo construct pattern in zebrafish in which light illumination is used to control oligomerization, phase transition, and aggregation of the ALS-associated DNA/RNA-binding protein TDP-43. It is presented as an optogenetic disease model for studying ALS-related TDP-43 protein state changes.

OptoLoop is an optogenetic multi-component switch for light-controlled manipulation of chromatin contacts. It is built from nuclease-dead Streptococcus pyogenes Cas9 fused to the light-inducible oligomerizing protein CRY2 and is reported to induce contacts between genomically distant repetitive DNA loci.

optoRAF is an optogenetic multi-component switch for light-controlled clustering and activation of RAF proteins. It was described as mimicking naturally occurring RAS-mediated RAF dimerization and was used to probe BRAF and CRAF responses to kinase inhibitors.

OptoREACT is a light-dependent extracellular receptor activation system for nonengineered cells. It combines phytochrome B with a PIF6-coupled antibody fragment to bind cell-surface receptors and, upon illumination, drive receptor oligomerization and activation, including the T cell receptor on Jurkat and primary human T cells.

optoRET is an optogenetic RET signaling switch created by fusing the cytosolic region of human RET to a blue-light-inducible homo-oligomerizing protein. Blue-light stimulation modulates RET pathway output, including Grb2 recruitment and activation of AKT and ERK, and can also induce local filopodia-like F-actin structures through Cdc42 activation.

optoSynC is a non-ionic optogenetic silencer that uses light-evoked homo-oligomerization of cryptochrome CRY2 to cluster synaptic vesicles and silence synaptic transmission. It was benchmarked in Caenorhabditis elegans, zebrafish, and murine hippocampal neurons.

Photoactivatable cyclic caged morpholino oligomers (ccMOs) are light-responsive antisense morpholino reagents engineered in a cyclic, caged format to suppress target binding until photoactivation. In the reported design, brief 405-nm illumination photocleaves the cage and restores antisense activity, enabling spatiotemporal regulation of gene expression.

The PHR domain of Arabidopsis thaliana cryptochrome 2 is a blue-light-responsive protein domain that self-oligomerizes upon illumination. In the cited optogenetic application, it was fused into a construct that rapidly modulated caspase-8 activation, leading to caspase-3 accumulation and induction of apoptosis.

Q-PAS1 is an engineered single-domain binding partner for the bacterial phytochrome BphP1 that enables near-infrared-light-inducible protein interactions. It was developed as a smaller, non-oligomerizing alternative to the natural BphP1 partner PpsR2 and has been applied to transcription regulation, chromatin state modification, and spectral multiplexing.

Single-headed kinesin molecular motors with optically enhanced clustering are engineered motors for microtubule-based active fluids that allow light-dependent control of extensile active stress. In the reported system, they support precise and repeatable spatiotemporal patterning of activity and rapid, reversible switching between flowing and quiescent states.

Synthetic condensates are an engineered modular system for building synthetic membraneless organelles that separates condensate assembly from client recruitment. The framework uses constitutive oligomerization of intrinsically disordered regions to form clusters and fused interaction domains to define condensate composition.

The theoretical probability of neighbor density (PND) is a computational method introduced to discern protein oligomeric states in cellular environments. It is described as robust, precise, and adaptable for analyzing oligomerization scenarios spanning monomers to hexamers.

The TRIM21 RING domain is a catalytic protein domain whose ubiquitination activity is activated by substrate-induced clustering that promotes intermolecular RING dimerization. In the cited 2020 study, this activation mechanism underlies TRIM21-dependent antiviral responses and Trim-Away-mediated protein degradation.