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Structure and mechanism of the type I-G CRISPR effector
Type I CRISPR systems are the most common CRISPR type found in bacteria. They use a multisubunit effector, guided by crRNA, to detect and bind dsDNA targets, forming an R-loop and recruiting the Cas3 enzyme to facilitate target DNA destruction, thus providing immunity against mobile genetic elements...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Oxford University Press
2022
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9638904/ https://www.ncbi.nlm.nih.gov/pubmed/36305833 http://dx.doi.org/10.1093/nar/gkac925 |
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author | Shangguan, Qilin Graham, Shirley Sundaramoorthy, Ramasubramanian White, Malcolm F |
author_facet | Shangguan, Qilin Graham, Shirley Sundaramoorthy, Ramasubramanian White, Malcolm F |
author_sort | Shangguan, Qilin |
collection | PubMed |
description | Type I CRISPR systems are the most common CRISPR type found in bacteria. They use a multisubunit effector, guided by crRNA, to detect and bind dsDNA targets, forming an R-loop and recruiting the Cas3 enzyme to facilitate target DNA destruction, thus providing immunity against mobile genetic elements. Subtypes have been classified into families A-G, with type I-G being the least well understood. Here, we report the composition, structure and function of the type I-G Cascade CRISPR effector from Thioalkalivibrio sulfidiphilus, revealing key new molecular details. The unique Csb2 subunit processes pre-crRNA, remaining bound to the 3′ end of the mature crRNA, and seven Cas7 subunits form the backbone of the effector. Cas3 associates stably with the effector complex via the Cas8g subunit and is important for target DNA recognition. Structural analysis by cryo-Electron Microscopy reveals a strikingly curved backbone conformation with Cas8g spanning the belly of the structure. These biochemical and structural insights shed new light on the diversity of type I systems and open the way to applications in genome engineering. |
format | Online Article Text |
id | pubmed-9638904 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | Oxford University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-96389042022-11-07 Structure and mechanism of the type I-G CRISPR effector Shangguan, Qilin Graham, Shirley Sundaramoorthy, Ramasubramanian White, Malcolm F Nucleic Acids Res Nucleic Acid Enzymes Type I CRISPR systems are the most common CRISPR type found in bacteria. They use a multisubunit effector, guided by crRNA, to detect and bind dsDNA targets, forming an R-loop and recruiting the Cas3 enzyme to facilitate target DNA destruction, thus providing immunity against mobile genetic elements. Subtypes have been classified into families A-G, with type I-G being the least well understood. Here, we report the composition, structure and function of the type I-G Cascade CRISPR effector from Thioalkalivibrio sulfidiphilus, revealing key new molecular details. The unique Csb2 subunit processes pre-crRNA, remaining bound to the 3′ end of the mature crRNA, and seven Cas7 subunits form the backbone of the effector. Cas3 associates stably with the effector complex via the Cas8g subunit and is important for target DNA recognition. Structural analysis by cryo-Electron Microscopy reveals a strikingly curved backbone conformation with Cas8g spanning the belly of the structure. These biochemical and structural insights shed new light on the diversity of type I systems and open the way to applications in genome engineering. Oxford University Press 2022-10-28 /pmc/articles/PMC9638904/ /pubmed/36305833 http://dx.doi.org/10.1093/nar/gkac925 Text en © The Author(s) 2022. Published by Oxford University Press on behalf of Nucleic Acids Research. https://creativecommons.org/licenses/by/4.0/This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. |
spellingShingle | Nucleic Acid Enzymes Shangguan, Qilin Graham, Shirley Sundaramoorthy, Ramasubramanian White, Malcolm F Structure and mechanism of the type I-G CRISPR effector |
title | Structure and mechanism of the type I-G CRISPR effector |
title_full | Structure and mechanism of the type I-G CRISPR effector |
title_fullStr | Structure and mechanism of the type I-G CRISPR effector |
title_full_unstemmed | Structure and mechanism of the type I-G CRISPR effector |
title_short | Structure and mechanism of the type I-G CRISPR effector |
title_sort | structure and mechanism of the type i-g crispr effector |
topic | Nucleic Acid Enzymes |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9638904/ https://www.ncbi.nlm.nih.gov/pubmed/36305833 http://dx.doi.org/10.1093/nar/gkac925 |
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