Structural highlights
Publication Abstract from PubMedNaturally existing enzymes have been adapted for a variety of molecular technologies, with enhancements or modifications to the enzymes introduced to improve the desired function; however, it is difficult to engineer variants with enhanced activity while maintaining specificity. Here we engineer the compact Obligate Mobile Element Guided Activity (OMEGA) RNA-guided endonuclease IscB and its guiding RNA (omegaRNA) by combining ortholog screening, structure-guided protein domain design and RNA engineering, and deep learning-based structure prediction to generate an improved variant, NovaIscB. We show that the compact NovaIscB achieves up to 40% indel activity (~100-fold improvement over wild-type OgeuIscB) on the human genome with improved specificity relative to existing IscBs. We further show that NovaIscB can be fused with a methyltransferase to create a programmable transcriptional repressor, OMEGAoff, that is compact enough to be packaged in a single adeno-associated virus vector for persistent in vivo gene repression. This study highlights the power of combining natural diversity with protein engineering to design enhanced enzymes for molecular biology applications. Evolution-guided protein design of IscB for persistent epigenome editing in vivo.,Kannan S, Altae-Tran H, Zhu S, Xu P, Strebinger D, Oshiro R, Faure G, Moeller L, Pham J, Mears KS, Ni HM, Macrae RK, Zhang F Nat Biotechnol. 2025 May 7. doi: 10.1038/s41587-025-02655-3. PMID:40335752[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
This page was last modified 07:14, 3 June 2026.