Structure of the Saccharolobus solfataricus type III-D CRISPR effector.
Structure of the Saccharolobus solfataricus type III-D CRISPR effector.
复制标题
DOI：
10.1016/j.crstbi.2023.100098
复制
发表时间：
2023
影响因子：
2.8
通讯作者：
Spagnolo, Laura
中科院分区：
文献类型：
--
作者：
Cannone, Giuseppe;Kompaniiets, Dmytro;Graham, Shirley;White, Malcolm F;Spagnolo, Laura
CRISPR-Cas是一种原核生物适应性免疫系统，分为六种不同的类型，每种类型都有一个特征蛋白。根据Cas10亚基的存在进行分类的III型系统是相当多样化的多亚基组件，具有一系列的酶活性和下游的辅助效应器。目前广泛的生物技术CRISPR应用主要是基于被归类为II型的蛋白质，然而最近的发展证实了多蛋白质III型CRISPR-Cas效应复合体作为真核生物中RNA靶向工具的可行性和有效性。Saccharolobus solfararicus有两个系统亚型(III-B和III-D)。在这里，我们报道了来自S.solfararicus的CSM III-D复合体(SsoCsm)的冷冻EM结构，它使用CRISPR RNA与靶RNA分子结合，激活Cas10亚单位进行抗病毒防御。该结构揭示了SsoCsm复合体的复杂组织、亚基/亚基连通性和蛋白质/引导RNA相互作用，SsoCsm复合体是已知最大的CRISPR效应器之一。III-D型CRISPR效应器SsoCsm是迄今为止研究的最大和最复杂的CRISPR效应器之一。SsoCsm有一个独特的复杂的Cas7主干结构，它由五个基因编码的七个亚基组成。SsoCsm结构显示出构象灵活性，这可能与靶RNA捕获和Cas10激活有关。
CRISPR-Cas is a prokaryotic adaptive immune system, classified into six different types, each characterised by a signature protein. Type III systems, classified based on the presence of a Cas10 subunit, are rather diverse multi-subunit assemblies with a range of enzymatic activities and downstream ancillary effectors. The broad array of current biotechnological CRISPR applications is mainly based on proteins classified as Type II, however recent developments established the feasibility and efficacy of multi-protein Type III CRISPR-Cas effector complexes as RNA-targeting tools in eukaryotes. The crenarchaeon Saccharolobus solfataricus has two type III system subtypes (III–B and III-D). Here, we report the cryo-EM structure of the Csm Type III-D complex from S. solfataricus (SsoCsm), which uses CRISPR RNA to bind target RNA molecules, activating the Cas10 subunit for antiviral defence. The structure reveals the complex organisation, subunit/subunit connectivity and protein/guide RNA interactions of the SsoCsm complex, one of the largest CRISPR effectors known. The type III-D CRISPR effector SsoCsm is one of the largest and most complex CRISPR effectors studied to date. SsoCsm has a uniquely complex Cas7 backbone structure, which is assembled from seven subunits encoded by five genes. The SsoCsm structure reveals conformational flexibility that likely relates to target RNA capture and Cas10 activation.
影响因子：
5.7
作者：
Smith, Eric M.;Ferrell, Se;Tokars, Valerie L.;Mondragon, Alfonso
通讯作者：
Mondragon, Alfonso