Photoactivation/regulation of CRISPR systems: From in vitro diagnosis to in vivo gene manipulation

CRISPR technology has extensive applications in the biomedical field, whether in in vitro molecular diagnosis or in vivo gene manipulation. However, CRISPR is not acme of perfection. On the one hand, when CRISPR is used in combination with isothermal amplification for nucleic acid detection, the detection performance will be reduced due to the competition between CRISPR and isothermal amplification. On the other hand, CRISPR lacks an effective and controllable regulatory approach in genetic manipulation. Light, with its non-invasive, low-damage and high-precision spatiotemporal control capabilities, provides an ideal solution for addressing these issues. In this review, the technical basis of light-regulated CRISPR, including the types and characteristics of photocage groups, as well as the light-regulated modification methods of nucleic acids and proteins, was introduced. Further, the application of this technology in in vitro diagnosis (such as in combination with isothermal amplification techniques) and in vivo manipulation (such as gene editing, transcriptional expression regulation, model construction and cancer treatment) was summarized. Finally, the future development directions such as optimizing the performance of photosensitive groups, breaking through the bottleneck of technical compatibility, enhancing the accuracy of spatio-temporal control, and expanding cross-disciplinary applications were looked forward to.