Researchers have utilized a bacterial immune defense system called CRISPR to effectively and accurately regulate RNA splicing. This breakthrough technology enables new possibilities, including systematically studying gene functions and correcting splicing defects linked to various diseases and disorders.
Researchers at the University of Toronto have leveraged CRISPR to control RNA splicing with precision.
This advancement allows for exploring new applications like investigating gene components and addressing splicing irregularities causing diseases.
“Most human genes produce RNA transcripts that undergo splicing, where coding sections (exons) are connected while non-coding sections (introns) are removed,” explained Jack Daiyang Li, the study’s first author and a molecular genetics PhD student at the Donnelly Centre for Cellular and Biomolecular Research at U of T.
Exons can undergo alternative splicing, enhancing the diversity of protein-coding genes and enabling cell specialization.
However, the functions of many exons and introns remain unclear, and disruptions in normal splicing processes are often linked to diseases like cancer and brain disorders. Yet, precise and efficient splicing manipulation methods have been lacking.
In the recent study, researchers fused a deactivated RNA-targeting CRISPR protein, dCasRx, with over 300 splicing factors to create dCasRx-RBM25. This protein can activate or suppress alternative exons efficiently and specifically.
“Our new protein successfully activated around 90% of tested target exons, demonstrating the ability to manipulate different exons simultaneously to study their combined functions,” Li stated.
This multilayered control will aid in exploring the interactions between alternatively spliced gene variants to understand their roles in development and disease processes.
“Our innovative tool offers a wide range of applications, from gene studies to potentially correcting splicing defects in human diseases,” said Blencowe, the study’s principal investigator and a professor of molecular genetics at the Donnelly Centre and the Temerty Faculty of Medicine.
“We have created a versatile splicing factor that surpasses other available tools in controlling alternative exons with precision,” added Taipale, the study’s co-investigator and an associate professor of molecular genetics at the Donnelly Centre and Temerty Medicine. “This splicing factor perturbs target exons with exceptional specificity, minimizing concerns of unintended effects.”
The researchers now have a tool to systematically examine alternative exons to uncover their roles in cell functions, cell type specification, and gene expression.
Looking ahead, this splicing tool holds promise for treating various human disorders like autism and cancer, where splicing irregularities are common.
This study received funding from the Canadian Institutes of Health Research and the Simons Foundation.
