New light-controlled CRISPR tool enhances precision in genetic research
A team of researchers at Karolinska Institutet has developed a novel tool for genetic research. The study, published in Nucleic Acids Research, introduces BLU-VIPR, a method that allows researchers to control the gene-editing tool CRISPR using light. This innovation could significantly enhance our understanding of gene functions in complex organisms.
The ability to modify genes in specific areas of an organism at precise times has long been a challenge in genetic research. Traditional methods lack the necessary tools to achieve this level of control.
BLU-VIPR addresses this issue by enabling researchers to shine light on a specific anatomical area, such as a lymph node, to modify genes only in the illuminated region.
"Our new tool for light-induced CRISPR will enable researchers to understand the biological role of genes much more precisely, which in turn will increase our understanding of biological processes", says Alexander Espinosa, associate professor at the Department of Medicine Solna and last author of the article.
Innovative approach
The study details how the team engineered a potent light-induced transcription factor, VPR-EL222, by fusing a bacterial protein (EL222) with a transcription activation domain (VPR). When exposed to blue light, this transcription factor induces guide RNA (gRNA) in cells, which then binds to Cas9, leading to the editing of selected genes.
The researchers demonstrated the effectiveness of this system by performing gene knockouts, activations, and precise base editing in cells in vitro. They also incorporated the light-induced CRISPR system into viral vectors, successfully delivering it to primary T cells and achieving light-induced gene knockouts in T cells within the lymph nodes of mice.
Future directions
Looking ahead, the team is focused on refining the system to target genes in other immune cells beyond T cells. This advancement could open new avenues for research into immune responses and disease mechanisms.
The development of BLU-VIPR marks a significant step forward in genetic research, offering a powerful tool for scientists to explore the intricate roles of genes in multicellular organisms with unprecedented precision.
Publication
"Light-induced expression of gRNA allows for optogenetic gene editing of T lymphocytes in vivo", Pulgarin DV, Pelo N, Ferrandiz L, Tršelič T, Nyberg WA, Bowlin G, Espinosa A. Nucleic Acids Research, online 20 March 2025, doi: 10.1093/nar/gkaf213.