دورية أكاديمية
CRISPR-Cas12a exploits R-loop asymmetry to form double-strand breaks
| العنوان: | CRISPR-Cas12a exploits R-loop asymmetry to form double-strand breaks |
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| المؤلفون: | Cofsky, Joshua C, Karandur, Deepti, Huang, Carolyn J, Witte, Isaac P, Kuriyan, John, Doudna, Jennifer A |
| المساهمون: | Howard Hughes Medical Institute, National Science Foundation |
| المصدر: | eLife ; volume 9 ; ISSN 2050-084X |
| بيانات النشر: | eLife Sciences Publications, Ltd |
| سنة النشر: | 2020 |
| المجموعة: | eLife (E-Journal - via CrossRef) |
| الوصف: | Type V CRISPR-Cas interference proteins use a single RuvC active site to make RNA-guided breaks in double-stranded DNA substrates, an activity essential for both bacterial immunity and genome editing. The best-studied of these enzymes, Cas12a, initiates DNA cutting by forming a 20-nucleotide R-loop in which the guide RNA displaces one strand of a double-helical DNA substrate, positioning the DNase active site for first-strand cleavage. However, crystal structures and biochemical data have not explained how the second strand is cut to complete the double-strand break. Here, we detect intrinsic instability in DNA flanking the RNA-3′ side of R-loops, which Cas12a can exploit to expose second-strand DNA for cutting. Interestingly, DNA flanking the RNA-5′ side of R-loops is not intrinsically unstable. This asymmetry in R-loop structure may explain the uniformity of guide RNA architecture and the single-active-site cleavage mechanism that are fundamental features of all type V CRISPR-Cas systems. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| DOI: | 10.7554/elife.55143 |
| الإتاحة: | https://doi.org/10.7554/elife.55143Test https://cdn.elifesciences.org/articles/55143/elife-55143-v2.pdfTest https://cdn.elifesciences.org/articles/55143/elife-55143-v2.xmlTest https://elifesciences.org/articles/55143Test |
| حقوق: | http://creativecommons.org/licenses/by/4.0Test/ ; http://creativecommons.org/licenses/by/4.0Test/ ; http://creativecommons.org/licenses/by/4.0Test/ |
| رقم الانضمام: | edsbas.C3378865 |
| قاعدة البيانات: | BASE |
| DOI: | 10.7554/elife.55143 |
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