RNA structure modulates Cas13 activity and enables mismatch detection

Researchers have discovered that RNA structure plays a crucial role in modulating Cas13 activity, a key enzyme in RNA-targeting CRISPR systems. By developing an innovative CRISPR RNA occlusion strategy, they have significantly enhanced the enzyme's ability to detect mismatches, improving the specificity and accuracy of RNA editing technologies. Cas13 systems have emerged as powerful tools for RNA manipulation, offering precise targeting of RNA transcripts without modifying the genome. However, achieving high specificity has remained a challenge, as Cas13 can sometimes cleave unintended RNA targets with sequence similarities to the intended target. The research team, led by Benjamin B. Larsen, Ofer Kimchi, and Cameron Myhrvold, designed a novel approach that uses RNA structure to modulate Cas13 activity, enabling the system to more effectively distinguish between perfectly matched and mismatched target sequences. This discovery not only improves the precision of RNA editing but also paves the way for the development of safer and more reliable RNA-targeting therapeutic approaches. Published as an open-access article in Nature Biotechnology on October 23, 2025, this research represents a significant advancement in our understanding of CRISPR-Cas13 biology and its applications in biotechnology and medicine.