Optogenetic Control of Programmable Genome Editing by Photoactivatable CRISPR/Cas9 Nanosystem in the Second Near-Infrared Window

We herein report the first optogenetically activatable CRISPR/Cas9 nanosystem for programmable genome editing in the second near-infrared (NIR-II) optical window. The nanosystem is composed of a cationic polymer-coated gold nanorod (APC) and Cas9 plasmid driven by a heat-inducible promoter. APC not only serves as a carrier for intracellular plasmid delivery, but also can harvest external NIR-II photonic energy and convert into local heat to induce the gene expression of Cas9 endonuclease. Due to high transfection activity, APC shows strong ability to induce significant level of disruption in different genome loci upon optogenetic activation. Moreover, the precise control of genome editing activity can be simply programmed by finely tuning exposure time and irradiation times in vitro and in vivo, and also enables editing at multiple time points, thus proving the sensitivity and reversibility of such an editing modality. The NIR-II optical feature of APC enables therapeutic genome editing at the deep tissue of the tumor-bearing mice, by which tumor growth could be effectively inhibited as a proof-of-concept therapeutic example. Importantly, this modality of optogenetic genome editing can significantly minimize the off-target effect of CRISPR/Cas9 in the most potential off-target sites. The optogenetically activatable CRISPR/Cas9 nanosystem we have developed offers a useful tool to expand the current applications of CRISPR/Cas9, and also defines a programmable genome editing strategy towards unprecedented precision and spatiotemporal specificity.