Light-Triggered Genome Editing: Cre Recombinase Mediated Gene Editing with Near-Infrared Light.

A light-activated genome editing platform based on the release of enzymes from a plasmonic nanoparticle carrier when exposed to biocompatible near-infrared light pulses is described. The platform relies on the robust affinity of polyhistidine tags to nitrilotriacetic acid in the presence of copper which is attached to double-stranded nucleic acids self-assembled on the gold nanoparticle surface. A protein fusion of the Cre recombinase containing a TAT internalization peptide sequence to achieve endosomal localization is also employed. High-resolution gene knock-in of a red fluorescent reporter is observed using a commercial two-photon microscope. High-throughput irradiation is described to generate useful quantities of edited cells.

Affinity-Based Assembly of Peptides on Plasmonic Nanoparticles Delivered Intracellularly with Light Activated Control.

We report a universal strategy for functionalizing near-infrared light-responsive nanocarriers with both a peptide "cargo" and an orthogonal cell-penetrating peptide. Modularity of both the cargo and the internalization peptide attachment is an important feature of these materials relying on the robust affinity of polyhistidine tags to nitrilotriacetic acid in the presence of nickel as well as the affinity of biotin labeled peptides to streptavidin. Attachment to the gold surface uses thiol-labeled scaffolds terminated with the affinity partner. These materials allow for unprecedented spatiotemporal control over the release of the toxic α-helical amphipathic peptide (KLAKLAK)2 which disrupts mitochondrial membranes and initiates apoptotic cell death. Laser treatment at benign near-infrared wavelengths releases peptide from the gold surface as well as breaches the endosome barrier for cytosolic activity (with 105-fold improved response to peptide activity over the free peptide) and can be monitored in real time.