Curated Optogenetic Publication Database

Abstract: Engineered stem cells offer promise for organ regeneration but face challenges including off-target effects and limited homing. Here, we develop a novel optogenetic strategy that spatiotemporally engineers mesenchymal stromal cells (MSCs) for liver regeneration. Through single-cell sequencing analysis, we reveal the CXCR4/SDF1 axis as an important signaling pathway for MSC homing. By integrating the photosensitive component ultraviolet-B resistance locus 8 (UVR8) with the homing chemokine receptor CXCR4, we construct a spatiotemporal optogenetic system for MSC transfection. Upon UV irradiation, UVR8's dissociation property is activated, enabling photosensitive proteins to migrate from the endoplasmic reticulum to the golgi apparatus and subsequently release CXCR4 on the MSC membrane. To address the limited tissue penetration of UV, we incorporate upconversion nanoparticles (UCNPs) that convert near-infrared (NIR) light into UV. Following injection, UCNPs accumulate in the liver, where targeted NIR irradiation activates CXCR4/SDF1-mediated MSC homing. In a ConA-induced liver injury mouse model, the engineered MSCs regulate the SP1/SK1/S1P axis, thereby inhibiting necroptosis of intrahepatic macrophages. Moreover, hepatocyte proliferation is promoted via S1P/YAP signaling. In conclusion, our optogenetic strategy opens promising therapeutic avenues for the regeneration field and biomedical applications.

Abstract: Light-mediated release of signaling ligands, such as chemoattractants, growth factors, and cytokines is an attractive strategy for investigation and therapeutic targeting of leukocyte communication and immune responses. We introduce a versatile optogenetic method to control ligand secretion, combining UV-conditioned endoplasmic reticulum-to-Golgi trafficking and a furin-processing step. As proof of principle, we achieved light-triggered chemokine secretion and demonstrated that a brief pulse of chemokine release can mediate a rapid flux of leukocyte contacts with target cells in vitro and in vivo. This approach opens new possibilities for dynamic investigation of leukocyte communication in vivo and may confer the potential to control the local release of soluble mediators in the context of immune cell therapies.

Abstract: Responsive hydrogels hold great potential in controllable drug delivery, regenerative medicine, sensing, etc. We introduced in this study the first example of a photo-responsive protein for hydrogel formation. Based on the first example of the crystal structure of a photo-responsive protein, Arabidopsis thaliana protein UVR8, we designed and expressed its derived protein UVR8-1 with a hexa-peptide WRESAI. We also prepared supramolecular nanofibers with a TIP-1 protein at their surface. The simple mixing of these two components resulted in rapid hydrogel formation through the specific interactions between the protein TIP-1 and the peptide WRESAI. Since the protein could show a reversible dimer-monomer transformation, the resulting gels also showed a reversible gel-sol phase transition which was controlled by photo-irradiation. The photo-controllable gel-sol phase transition could be applied for protein delivery and cell separation.

Abstract: Optical control of protein interactions has emerged as a powerful experimental paradigm for manipulating and studying various cellular processes. Tools are now available for controlling a number of cellular functions, but some fundamental processes, such as protein secretion, have been difficult to engineer using current optical tools. Here we use UVR8, a plant photoreceptor protein that forms photolabile homodimers, to engineer the first light-triggered protein secretion system. UVR8 fusion proteins were conditionally sequestered in the endoplasmic reticulum, and a brief pulse of light triggered robust forward trafficking through the secretory pathway to the plasma membrane. UVR8 was not responsive to excitation light used to image cyan, green, or red fluorescent protein variants, allowing multicolor visualization of cellular markers and secreted protein cargo as it traverses the cellular secretory pathway. We implemented this novel tool in neurons to demonstrate restricted, local trafficking of secretory cargo near dendritic branch points.