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Hu T, Ji Q, Ke X, Zhou H, Zhang S, Ma S, Yu C, Ju W, Lu M, Lin Y, Ou Y, Zhou Y, Xiao Y, Xu C, Hu C. Repurposing Type I-A CRISPR-Cas3 for a robust diagnosis of human papillomavirus (HPV). Commun Biol 2024; 7:858. [PMID: 39003402 PMCID: PMC11246428 DOI: 10.1038/s42003-024-06537-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 07/03/2024] [Indexed: 07/15/2024] Open
Abstract
R-loop-triggered collateral single-stranded DNA (ssDNA) nuclease activity within Class 1 Type I CRISPR-Cas systems holds immense potential for nucleic acid detection. However, the hyperactive ssDNase activity of Cas3 introduces unwanted noise and false-positive results. In this study, we identified a novel Type I-A Cas3 variant derived from Thermococcus siculi, which remains in an auto-inhibited state until it is triggered by Cascade complex and R-loop formation. This Type I-A CRISPR-Cas3 system not only exhibits an expanded protospacer adjacent motif (PAM) recognition capability but also demonstrates remarkable intolerance towards mismatched sequences. Furthermore, it exhibits dual activation modes-responding to both DNA and RNA targets. The culmination of our research efforts has led to the development of the Hyper-Active-Verification Establishment (HAVE, ). This innovation enables swift and precise human papillomavirus (HPV) diagnosis in clinical samples, providing a robust molecular diagnostic tool based on the Type I-A CRISPR-Cas3 system. Our findings contribute to understanding type I-A CRISPR-Cas3 system regulation and facilitate the creation of advanced diagnostic solutions with broad clinical applicability.
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Affiliation(s)
- Tao Hu
- Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Zhejiang University, Hangzhou, Zhejiang, 310052, China
| | - Quanquan Ji
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
| | - Xinxin Ke
- Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Zhejiang University, Hangzhou, Zhejiang, 310052, China
| | - Hufeng Zhou
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Senfeng Zhang
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Singapore
| | - Shengsheng Ma
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Singapore
| | - Chenlin Yu
- Department of Biochemistry, School of Life Science and Technology, China Pharmaceutical University, Nanjing, 211198, China
| | - Wenjun Ju
- Department of Biochemistry, School of Life Science and Technology, China Pharmaceutical University, Nanjing, 211198, China
| | - Meiling Lu
- Department of Biochemistry, School of Life Science and Technology, China Pharmaceutical University, Nanjing, 211198, China
| | - Yu Lin
- International Peace Maternity & Child Health Hospital, Shanghai Municipal Key Clinical Specialty, Institute of Embryo-Fetal Original Adult Disease, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Yangjing Ou
- International Peace Maternity & Child Health Hospital, Shanghai Municipal Key Clinical Specialty, Institute of Embryo-Fetal Original Adult Disease, School of Medicine, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Yingsi Zhou
- HuidaGene Therapeutics Inc., Shanghai, China.
| | - Yibei Xiao
- Department of Biochemistry, School of Life Science and Technology, China Pharmaceutical University, Nanjing, 211198, China.
| | - Chunlong Xu
- Lingang Laboratory, Shanghai, China.
- School of Life Sciences and Technology, ShanghaiTech University, Shanghai, China.
- Shanghai Center for Brain Science and Brain-Inspired Technology, Shanghai, China.
| | - Chunyi Hu
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, 117543, Singapore.
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore.
- Precision Medicine Translational Research Programme (TRP), Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Singapore.
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2
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Kansal R. The CRISPR-Cas System and Clinical Applications of CRISPR-Based Gene Editing in Hematology with a Focus on Inherited Germline Predisposition to Hematologic Malignancies. Genes (Basel) 2024; 15:863. [PMID: 39062641 PMCID: PMC11276294 DOI: 10.3390/genes15070863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2024] [Revised: 06/27/2024] [Accepted: 06/27/2024] [Indexed: 07/28/2024] Open
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR)-based gene editing has begun to transform the treatment landscape of genetic diseases. The history of the discovery of CRISPR/CRISPR-associated (Cas) proteins/single-guide RNA (sgRNA)-based gene editing since the first report of repetitive sequences of unknown significance in 1987 is fascinating, highly instructive, and inspiring for future advances in medicine. The recent approval of CRISPR-Cas9-based gene therapy to treat patients with severe sickle cell anemia and transfusion-dependent β-thalassemia has renewed hope for treating other hematologic diseases, including patients with a germline predisposition to hematologic malignancies, who would benefit greatly from the development of CRISPR-inspired gene therapies. The purpose of this paper is three-fold: first, a chronological description of the history of CRISPR-Cas9-sgRNA-based gene editing; second, a brief description of the current state of clinical research in hematologic diseases, including selected applications in treating hematologic diseases with CRISPR-based gene therapy, preceded by a brief description of the current tools being used in clinical genome editing; and third, a presentation of the current progress in gene therapies in inherited hematologic diseases and bone marrow failure syndromes, to hopefully stimulate efforts towards developing these therapies for patients with inherited bone marrow failure syndromes and other inherited conditions with a germline predisposition to hematologic malignancies.
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Affiliation(s)
- Rina Kansal
- Molecular Oncology and Genetics, Diagnostic Laboratories, Versiti Blood Center of Wisconsin, Milwaukee, WI 53233, USA;
- Department of Pathology and Anatomical Sciences, The University at Buffalo, Buffalo, NY 14260, USA
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3
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Chi H, White MF. RNA processing by the CRISPR-associated NYN ribonuclease. Biochem J 2024; 481:793-804. [PMID: 38785320 PMCID: PMC11346440 DOI: 10.1042/bcj20240151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 05/22/2024] [Accepted: 05/24/2024] [Indexed: 05/25/2024]
Abstract
CRISPR-Cas systems confer adaptive immunity in prokaryotes, facilitating the recognition and destruction of invasive nucleic acids. Type III CRISPR systems comprise large, multisubunit ribonucleoprotein complexes with a catalytic Cas10 subunit. When activated by the detection of foreign RNA, Cas10 generates nucleotide signalling molecules that elicit an immune response by activating ancillary effector proteins. Among these systems, the Bacteroides fragilis type III CRISPR system was recently shown to produce a novel signal molecule, SAM-AMP, by conjugating ATP and SAM. SAM-AMP regulates a membrane effector of the CorA family to provide immunity. Here, we focus on NYN, a ribonuclease encoded within this system, probing its potential involvement in crRNA maturation. Structural modelling and in vitro ribonuclease assays reveal that NYN displays robust sequence-nonspecific, Mn2+-dependent ssRNA-cleavage activity. Our findings suggest a role for NYN in trimming crRNA intermediates into mature crRNAs, which is necessary for type III CRISPR antiviral defence. This study sheds light on the functional relevance of CRISPR-associated NYN proteins and highlights the complexity of CRISPR-mediated defence strategies in bacteria.
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Affiliation(s)
- Haotian Chi
- School of Biology, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
| | - Malcolm F. White
- School of Biology, University of St Andrews, St Andrews, Fife KY16 9ST, U.K
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4
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Ganguly C, Rostami S, Long K, Aribam SD, Rajan R. Unity among the diverse RNA-guided CRISPR-Cas interference mechanisms. J Biol Chem 2024; 300:107295. [PMID: 38641067 PMCID: PMC11127173 DOI: 10.1016/j.jbc.2024.107295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 04/08/2024] [Accepted: 04/10/2024] [Indexed: 04/21/2024] Open
Abstract
CRISPR-Cas (clustered regularly interspaced short palindromic repeats-CRISPR-associated) systems are adaptive immune systems that protect bacteria and archaea from invading mobile genetic elements (MGEs). The Cas protein-CRISPR RNA (crRNA) complex uses complementarity of the crRNA "guide" region to specifically recognize the invader genome. CRISPR effectors that perform targeted destruction of the foreign genome have emerged independently as multi-subunit protein complexes (Class 1 systems) and as single multi-domain proteins (Class 2). These different CRISPR-Cas systems can cleave RNA, DNA, and protein in an RNA-guided manner to eliminate the invader, and in some cases, they initiate programmed cell death/dormancy. The versatile mechanisms of the different CRISPR-Cas systems to target and destroy nucleic acids have been adapted to develop various programmable-RNA-guided tools and have revolutionized the development of fast, accurate, and accessible genomic applications. In this review, we present the structure and interference mechanisms of different CRISPR-Cas systems and an analysis of their unified features. The three types of Class 1 systems (I, III, and IV) have a conserved right-handed helical filamentous structure that provides a backbone for sequence-specific targeting while using unique proteins with distinct mechanisms to destroy the invader. Similarly, all three Class 2 types (II, V, and VI) have a bilobed architecture that binds the RNA-DNA/RNA hybrid and uses different nuclease domains to cleave invading MGEs. Additionally, we highlight the mechanistic similarities of CRISPR-Cas enzymes with other RNA-cleaving enzymes and briefly present the evolutionary routes of the different CRISPR-Cas systems.
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Affiliation(s)
- Chhandosee Ganguly
- Department of Chemistry and Biochemistry, Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, University of Oklahoma, Norman, Oklahoma, USA
| | - Saadi Rostami
- Department of Chemistry and Biochemistry, Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, University of Oklahoma, Norman, Oklahoma, USA
| | - Kole Long
- Department of Chemistry and Biochemistry, Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, University of Oklahoma, Norman, Oklahoma, USA
| | - Swarmistha Devi Aribam
- Department of Chemistry and Biochemistry, Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, University of Oklahoma, Norman, Oklahoma, USA
| | - Rakhi Rajan
- Department of Chemistry and Biochemistry, Price Family Foundation Institute of Structural Biology, Stephenson Life Sciences Research Center, University of Oklahoma, Norman, Oklahoma, USA.
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5
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Anand V, Prabhakaran HS, Prakash A, Hussain MS, Kumar M. Differential processing of CRISPR RNA by LinCas5c and LinCas6 of Leptospira. Biochim Biophys Acta Gen Subj 2023; 1867:130469. [PMID: 37797871 DOI: 10.1016/j.bbagen.2023.130469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 09/22/2023] [Accepted: 09/25/2023] [Indexed: 10/07/2023]
Abstract
Leptospira interrogans serovar Copenhageni's genome harbors two CRISPR-Cas systems belonging to subtypes I-B and I-C. However, in L. interrogans, the subtype I-C locus lacks an array component essential for assembling an interference complex. Thus, the reason for sustaining the expense of a cluster of cas genes (I-C) is obscure. Type I-C (previously Dvulg) is the only CRISPR subtype that engages Cas5c, a Cas5 variant, to process precursor CRISPR-RNA (pre-crRNA). In this study, thus, the recombinant Cas5c (rLinCas5c) of L.interrogans and its mutant variants were cloned, expressed, and purified. The purified rLinCas5c is illustrated as metal-independent, sequence, and size-specific cleavage on repeat RNA and pre-crRNA of subtype I-B or orphan CRISPR array. However, the Cas6-bound mature crRNA of subtype I-B fends off from the rLinCas5c activity. In addition, rLinCas5c holds metal and size-dependent DNase activity. The bioinformatics analysis of LinCas5c inferred that it belongs to the subgroup Cas5c-B. Substitution of Phe141 with a more conserved His residue and deletion of unique (β1'-β2') insertions usher a gain of rLinCas5c activity over nucleic acid. Overall, our results uncover the functional diversity of Cas5c ribonucleases and infer an incognito auxiliary role in the absence of a cognate CRISPR array.
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Affiliation(s)
- Vineet Anand
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Harshini Sheeja Prabhakaran
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Aman Prakash
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Md Saddam Hussain
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Manish Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
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6
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Hamdi I, Boni F, Shen Q, Moukendza L, Peibo LI, Jianping X. Characteristics of subtype III-A CRISPR-Cas system in Mycobacterium tuberculosis: An overview. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2023; 112:105445. [PMID: 37217031 DOI: 10.1016/j.meegid.2023.105445] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 04/03/2023] [Accepted: 05/19/2023] [Indexed: 05/24/2023]
Abstract
CRISPR-Cas systems are the only RNA- guided adaptive immunity pathways that trigger the detection and destruction of invasive phages and plasmids in bacteria and archaea. Due to its prevalence and mystery, the Class 1 CRISPR-Cas system has lately been the subject of several studies. This review highlights the specificity of CRISPR-Cas system III-A in Mycobacterium tuberculosis, the tuberculosis-causing pathogen, for over twenty years. We discuss the difference between the several subtypes of Type III and their defence mechanisms. The anti-CRISPRs (Acrs) recently described, the critical role of Reverse transcriptase (RT) and housekeeping nuclease for type III CRISPR-Cas systems, and the use of this cutting-edge technology, its impact on the search for novel anti-tuberculosis drugs.
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Affiliation(s)
- Insaf Hamdi
- Institute of Modern Biopharmaceuticals State Key Laboratory, Breeding Base Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400700, China
| | - Funmilayo Boni
- Institute of Modern Biopharmaceuticals State Key Laboratory, Breeding Base Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400700, China
| | - Qinglei Shen
- Institute of Modern Biopharmaceuticals State Key Laboratory, Breeding Base Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400700, China
| | - Liadrine Moukendza
- Institute of Modern Biopharmaceuticals State Key Laboratory, Breeding Base Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400700, China
| | - L I Peibo
- Chongqing Public Health Medical Center, Southwest University Public Health Hospital, China
| | - Xie Jianping
- Institute of Modern Biopharmaceuticals State Key Laboratory, Breeding Base Eco-Environment and Bio-Resource of the Three Gorges Area, Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, School of Life Sciences, Southwest University, Chongqing 400700, China; Chongqing Public Health Medical Center, Southwest University Public Health Hospital, China.
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7
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Pham A, Bassett S, Chen W, Da Silva NA. Assembly of Metabolons in Yeast Using Cas6-Mediated RNA Scaffolding. ACS Synth Biol 2023; 12:1164-1174. [PMID: 36920425 DOI: 10.1021/acssynbio.2c00650] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Cells often localize pathway enzymes in close proximity to reduce substrate loss via diffusion and to ensure that carbon flux is directed toward the desired product. To emulate this strategy for the biosynthesis of heterologous products in yeast, we have taken advantage of the highly specific Cas6-RNA interaction and the predictability of RNA hybridizations to demonstrate Cas6-mediated RNA-guided protein assembly within the yeast cytosol. The feasibility of this synthetic scaffolding technique for protein localization was first demonstrated using a split luciferase reporter system with each part fused to a different Cas6 protein. In Saccharomyces cerevisiae, the luminescence signal increased 3.6- to 20-fold when the functional RNA scaffold was also expressed. Expression of a trigger RNA, designed to prevent the formation of a functional scaffold by strand displacement, decreased the luminescence signal by nearly 2.3-fold. Temporal control was also possible, with induction of scaffold expression resulting in an up to 11.6-fold increase in luminescence after 23 h. Cas6-mediated assembly was applied to create a two-enzyme metabolon to redirect a branch of the violacein biosynthesis pathway. Localizing VioC and VioE together increased the amount of deoxyviolacein (desired) relative to prodeoxyviolacein (undesired) by 2-fold. To assess the generality of this colocalization method in other yeast systems, the split luciferase reporter system was evaluated in Kluyveromyces marxianus; RNA scaffold expression resulted in an increase in the luminescence signal of up to 1.9-fold. The simplicity and flexibility of the design suggest that this strategy can be used to create metabolons in a wide range of recombinant hosts of interest.
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Affiliation(s)
- Anhuy Pham
- Department of Chemical and Biomolecular Engineering, University of California, Irvine, California 92697-2580, United States
| | - Shane Bassett
- Department of Chemical and Biomolecular Engineering, University of California, Irvine, California 92697-2580, United States
| | - Wilfred Chen
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, United States
| | - Nancy A Da Silva
- Department of Chemical and Biomolecular Engineering, University of California, Irvine, California 92697-2580, United States
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8
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Jianwei L, Jobichen C, Machida S, Meng S, Read RJ, Hongying C, Jian S, Yuan YA, Sivaraman J. Structures of apo Cas12a and its complex with crRNA and DNA reveal the dynamics of ternary complex formation and target DNA cleavage. PLoS Biol 2023; 21:e3002023. [PMID: 36917574 PMCID: PMC10013913 DOI: 10.1371/journal.pbio.3002023] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 02/06/2023] [Indexed: 03/15/2023] Open
Abstract
Cas12a is a programmable nuclease for adaptive immunity against invading nucleic acids in CRISPR-Cas systems. Here, we report the crystal structures of apo Cas12a from Lachnospiraceae bacterium MA2020 (Lb2) and the Lb2Cas12a+crRNA complex, as well as the cryo-EM structure and functional studies of the Lb2Cas12a+crRNA+DNA complex. We demonstrate that apo Lb2Cas12a assumes a unique, elongated conformation, whereas the Lb2Cas12a+crRNA binary complex exhibits a compact conformation that subsequently rearranges to a semi-open conformation in the Lb2Cas12a+crRNA+DNA ternary complex. Notably, in solution, apo Lb2Cas12a is dynamic and can exist in both elongated and compact forms. Residues from Met493 to Leu523 of the WED domain undergo major conformational changes to facilitate the required structural rearrangements. The REC lobe of Lb2Cas12a rotates 103° concomitant with rearrangement of the hinge region close to the WED and RuvC II domains to position the RNA-DNA duplex near the catalytic site. Our findings provide insight into crRNA recognition and the mechanism of target DNA cleavage.
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Affiliation(s)
- Li Jianwei
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Chacko Jobichen
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Satoru Machida
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Sun Meng
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Randy J. Read
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | - Chen Hongying
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Shi Jian
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Yuren Adam Yuan
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - J. Sivaraman
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
- * E-mail:
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9
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Kolasinliler G, Aagre MM, Akkale C, Kaya HB. The use of CRISPR-Cas-based systems in bacterial cell factories. Biochem Eng J 2023. [DOI: 10.1016/j.bej.2023.108880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
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10
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Cheng F, Wu A, Liu C, Cao X, Wang R, Shu X, Wang L, Zhang Y, Xiang H, Li M. The toxin-antitoxin RNA guards of CRISPR-Cas evolved high specificity through repeat degeneration. Nucleic Acids Res 2022; 50:9442-9452. [PMID: 36018812 PMCID: PMC9458426 DOI: 10.1093/nar/gkac712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 07/30/2022] [Accepted: 08/10/2022] [Indexed: 12/24/2022] Open
Abstract
Recent discovery of ectopic repeats (outside CRISPR arrays) provided unprecedented insights into the nondefense roles of CRISPR-Cas. A striking example is the addiction module CreTA (CRISPR-regulated toxin-antitoxins), where one or two (in most cases) ectopic repeats produce CRISPR-resembling antitoxic (CreA) RNAs that direct the CRISPR effector Cascade to transcriptionally repress a toxic RNA (CreT). Here, we demonstrated that CreTA repeats are extensively degenerated in sequence, with the first repeat (ψR1) being more diverged than the second one (ψR2). As a result, such addiction modules become highly specific to their physically-linked CRISPR-Cas loci, and in most cases, CreA could not harness a heterologous CRISPR-Cas to suppress its cognate toxin. We further disclosed that this specificity primarily derives from the degeneration of ψR1, and could generally be altered by modifying this repeat element. We also showed that the degenerated repeats of CreTA were insusceptible to recombination and thus more stable compared to a typical CRISPR array, which could be exploited to develop highly stable CRISPR-based tools. These data illustrated that repeat degeneration (a common feature of ectopic repeats) improves the stability and specificity of CreTA in protecting CRISPR-Cas, which could have contributed to the widespread occurrence and deep diversification of CRISPR systems.
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Affiliation(s)
| | | | | | - Xifeng Cao
- School of life Sciences, Hebei University, Baoding, Hebei, China
| | - Rui Wang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xian Shu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Lingyun Wang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China,College of Plant Protection, Shandong Agricultural University, Taian, Shandong, China
| | - Yihan Zhang
- School of life Sciences, Hebei University, Baoding, Hebei, China,CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Hua Xiang
- Correspondence may also be addressed to Hua Xiang.
| | - Ming Li
- To whom correspondence should be addressed. Tel: +86 10 64807064; Fax: +86 10 64807064;
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11
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Jones SP, Goossen C, Lewis SD, Delaney AM, Gleghorn ML. Not making the cut: Techniques to prevent RNA cleavage in structural studies of RNase-RNA complexes. J Struct Biol X 2022; 6:100066. [PMID: 35340590 PMCID: PMC8943300 DOI: 10.1016/j.yjsbx.2022.100066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 11/16/2022] Open
Abstract
RNases are varied in the RNA structures and sequences they target for cleavage and are an important type of enzyme in cells. Despite the numerous examples of RNases known, and of those with determined three-dimensional structures, relatively few examples exist with the RNase bound to intact cognate RNA substrate prior to cleavage. To better understand RNase structure and sequence specificity for RNA targets, in vitro methods used to assemble these enzyme complexes trapped in a pre-cleaved state have been developed for a number of different RNases. We have surveyed the Protein Data Bank for such structures and in this review detail methodologies that have successfully been used and relate them to the corresponding structures. We also offer ideas and suggestions for future method development. Many strategies within this review can be used in combination with X-ray crystallography, as well as cryo-EM, and other structure-solving techniques. Our hope is that this review will be used as a guide to resolve future yet-to-be-determined RNase-substrate complex structures.
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Affiliation(s)
- Seth P. Jones
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
| | - Christian Goossen
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Lothrop St, Pittsburgh, PA 15261, United States
| | - Sean D. Lewis
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
- Mayo Clinic, 200 1st St SW, Rochester, MN 5590, United States
| | - Annie M. Delaney
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
| | - Michael L. Gleghorn
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
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12
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Abstract
CRISPR-Cas adaptive immune systems in bacteria and archaea utilize short CRISPR RNAs (crRNAs) to guide sequence-specific recognition and clearance of foreign genetic material. Multiple crRNAs are stored together in a compact format called a CRISPR array that is transcribed and processed into the individual crRNAs. While the exact processing mechanisms vary widely, some CRISPR-Cas systems, including those encoding the Cas9 nuclease, rely on a trans-activating crRNA (tracrRNA). The tracrRNA was discovered in 2011 and was quickly co-opted to create single-guide RNAs as core components of CRISPR-Cas9 technologies. Since then, further studies have uncovered processes extending beyond the traditional role of tracrRNA in crRNA biogenesis, revealed Cas nucleases besides Cas9 that are dependent on tracrRNAs, and established new applications based on tracrRNA engineering. In this review, we describe the biology of the tracrRNA and how its ongoing characterization has garnered new insights into prokaryotic immune defense and enabled key technological advances.
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Affiliation(s)
- Chunyu Liao
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany;
| | - Chase L Beisel
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany;
- Medical Faculty, University of Würzburg, 97080 Würzburg, Germany
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13
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Guzmán NM, Esquerra-Ruvira B, Mojica FJM. Digging into the lesser-known aspects of CRISPR biology. Int Microbiol 2021; 24:473-498. [PMID: 34487299 PMCID: PMC8616872 DOI: 10.1007/s10123-021-00208-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 08/30/2021] [Accepted: 08/31/2021] [Indexed: 12/26/2022]
Abstract
A long time has passed since regularly interspaced DNA repeats were discovered in prokaryotes. Today, those enigmatic repetitive elements termed clustered regularly interspaced short palindromic repeats (CRISPR) are acknowledged as an emblematic part of multicomponent CRISPR-Cas (CRISPR associated) systems. These systems are involved in a variety of roles in bacteria and archaea, notably, that of conferring protection against transmissible genetic elements through an adaptive immune-like response. This review summarises the present knowledge on the diversity, molecular mechanisms and biology of CRISPR-Cas. We pay special attention to the most recent findings related to the determinants and consequences of CRISPR-Cas activity. Research on the basic features of these systems illustrates how instrumental the study of prokaryotes is for understanding biology in general, ultimately providing valuable tools for diverse fields and fuelling research beyond the mainstream.
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Affiliation(s)
- Noemí M Guzmán
- Dpto. Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain
| | - Belén Esquerra-Ruvira
- Dpto. Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain
| | - Francisco J M Mojica
- Dpto. Fisiología, Genética y Microbiología, Universidad de Alicante, Alicante, Spain.
- Instituto Multidisciplinar para el Estudio del Medio, Universidad de Alicante, Alicante, Spain.
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14
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Cheng F, Wang R, Yu H, Liu C, Yang J, Xiang H, Li M. Divergent degeneration of creA antitoxin genes from minimal CRISPRs and the convergent strategy of tRNA-sequestering CreT toxins. Nucleic Acids Res 2021; 49:10677-10688. [PMID: 34551428 PMCID: PMC8501985 DOI: 10.1093/nar/gkab821] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 09/02/2021] [Accepted: 09/08/2021] [Indexed: 11/13/2022] Open
Abstract
Aside from providing adaptive immunity, type I CRISPR-Cas was recently unearthed to employ a noncanonical RNA guide (CreA) to transcriptionally repress an RNA toxin (CreT). Here, we report that, for most archaeal and bacterial CreTA modules, the creA gene actually carries two flanking 'CRISPR repeats', which are, however, highly divergent and degenerated. By deep sequencing, we show that the two repeats give rise to an 8-nt 5' handle and a 22-nt 3' handle, respectively, i.e., the conserved elements of a canonical CRISPR RNA, indicating they both retained critical nucleotides for Cas6 processing during divergent degeneration. We also uncovered a minimal CreT toxin that sequesters the rare transfer RNA for isoleucine, tRNAIleCAU, with a six-codon open reading frame containing two consecutive AUA codons. To fully relieve its toxicity, both tRNAIleCAU overexpression and supply of extra agmatine (modifies the wobble base of tRNAIleCAU to decipher AUA codons) are required. By replacing AUA to AGA/AGG codons, we reprogrammed this toxin to sequester rare arginine tRNAs. These data provide essential information on CreTA origin and for future CreTA prediction, and enrich the knowledge of tRNA-sequestering small RNAs that are employed by CRISPR-Cas to get addictive to the host.
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Affiliation(s)
- Feiyue Cheng
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Rui Wang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,Non-coding RNA and Drug Discovery Key Laboratory of Sichuan Province, Chengdu Medical College, Chengdu, Sichuan, China
| | - Haiying Yu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Chao Liu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Jun Yang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,Center for Life Science, School of Life Sciences, Yunnan University, Kunming, China
| | - Hua Xiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Ming Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
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15
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Lemak S, Serbanescu MA, Khusnutdinova AN, Ruszkowski M, Beloglazova N, Xu X, Brown G, Cui H, Tan K, Joachimiak A, Cvitkovitch DG, Savchenko A, Yakunin AF. Structural and biochemical insights into CRISPR RNA processing by the Cas5c ribonuclease SMU1763 from Streptococcus mutans. J Biol Chem 2021; 297:101251. [PMID: 34592310 PMCID: PMC8524198 DOI: 10.1016/j.jbc.2021.101251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 09/13/2021] [Accepted: 09/24/2021] [Indexed: 12/01/2022] Open
Abstract
The cariogenic pathogen Streptococcus mutans contains two CRISPR systems (type I-C and type II-A) with the Cas5c protein (SmuCas5c) involved in processing of long CRISPR RNA transcripts (pre-crRNA) containing repeats and spacers to mature crRNA guides. In this study, we determined the crystal structure of SmuCas5c at a resolution of 1.72 Å, which revealed the presence of an N-terminal modified RNA recognition motif and a C-terminal twisted β-sheet domain with four bound sulphate molecules. Analysis of surface charge and residue conservation of the SmuCas5c structure suggested the location of an RNA-binding site in a shallow groove formed by the RNA recognition motif domain with several conserved positively charged residues (Arg39, Lys52, Arg109, Arg127, and Arg134). Purified SmuCas5c exhibited metal-independent ribonuclease activity against single-stranded pre-CRISPR RNAs containing a stem-loop structure with a seven-nucleotide stem and a pentaloop. We found SmuCas5c cleaves substrate RNA within the repeat sequence at a single cleavage site located at the 3'-base of the stem but shows significant tolerance to substrate sequence variations downstream of the cleavage site. Structure-based mutational analysis revealed that the conserved residues Tyr50, Lys120, and His121 comprise the SmuCas5c catalytic residues. In addition, site-directed mutagenesis of positively charged residues Lys52, Arg109, and Arg134 located near the catalytic triad had strong negative effects on the RNase activity of this protein, suggesting that these residues are involved in RNA binding. Taken together, our results reveal functional diversity of Cas5c ribonucleases and provide further insight into the molecular mechanisms of substrate selectivity and activity of these enzymes.
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Affiliation(s)
- Sofia Lemak
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - M Anca Serbanescu
- Faculty of Dentistry, Dental Research Institute, University of Toronto, Toronto, Ontario, Canada
| | - Anna N Khusnutdinova
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Milosz Ruszkowski
- Synchrotron Radiation Research Section of MCL, National Cancer Institute, Argonne, Illinois, USA
| | - Natalia Beloglazova
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Xiaohui Xu
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Greg Brown
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Hong Cui
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Kemin Tan
- X-Ray Science Division, Midwest Center for Structural Genomics and Structural Biology Center, Argonne National Laboratory, Argonne, Illinois, USA
| | - Andrzej Joachimiak
- X-Ray Science Division, Midwest Center for Structural Genomics and Structural Biology Center, Argonne National Laboratory, Argonne, Illinois, USA
| | - Dennis G Cvitkovitch
- Faculty of Dentistry, Dental Research Institute, University of Toronto, Toronto, Ontario, Canada
| | - Alexei Savchenko
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Alexander F Yakunin
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario, Canada; Centre for Environmental Biotechnology, School of Natural Sciences, Bangor University, Bangor, Gwynedd, UK.
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17
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Prakash A, Kumar M. Characterizing the transcripts of Leptospira CRISPR I-B array and its processing with endoribonuclease LinCas6. Int J Biol Macromol 2021; 182:785-795. [PMID: 33862076 DOI: 10.1016/j.ijbiomac.2021.04.066] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/08/2021] [Accepted: 04/10/2021] [Indexed: 12/26/2022]
Abstract
In Leptospira interrogans serovar Copenhageni, the CRISPR-Cas I-B locus possesses a CRISPR array between the two independent cas-operons. Using the reverse transcription-PCR and the in vitro endoribonuclease assay with Cas6 of Leptospira (LinCas6), we account that the CRISPR is transcriptionally active and is conventionally processed. The LinCas6 specifically excises at one site within the synthetic cognate repeat RNA or the repeats of precursor-CRISPR RNA (pre-crRNA) in the sense direction. In contrast, the antisense repeat RNA is cleaved at multiple sites. LinCas6 functions as a single turnover endoribonuclease on its repeat RNA substrate, where substitution of one of predicted active site residues (His38) resulted in reduced activity. This study highlights the comprehensive understanding of the Leptospira CRISPR array transcription and its processing by LinCas6 that is central to RNA-mediated CRISPR-Cas I-B adaptive immunity.
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Affiliation(s)
- Aman Prakash
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Manish Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
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History, evolution and classification of CRISPR-Cas associated systems. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 179:11-76. [PMID: 33785174 DOI: 10.1016/bs.pmbts.2020.12.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This chapter provides a detailed description of the history of CRISPR-Cas and its evolution into one of the most efficient genome-editing strategies. The chapter begins by providing information on early findings that were critical in deciphering the role of CRISPR-Cas associated systems in prokaryotes. It then describes how CRISPR-Cas had been evolved into an efficient genome-editing strategy. In the subsequent section, latest developments in the genome-editing approaches based on CRISPR-Cas are discussed. The chapter ends with the recent classification and possible evolution of CRISPR-Cas systems.
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19
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Abstract
Prokaryotes have developed numerous defense strategies to combat the constant threat posed by the diverse genetic parasites that endanger them. Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas loci guard their hosts with an adaptive immune system against foreign nucleic acids. Protection starts with an immunization phase, in which short pieces of the invader's genome, known as spacers, are captured and integrated into the CRISPR locus after infection. Next, during the targeting phase, spacers are transcribed into CRISPR RNAs (crRNAs) that guide CRISPR-associated (Cas) nucleases to destroy the invader's DNA or RNA. Here we describe the many different molecular mechanisms of CRISPR targeting and how they are interconnected with the immunization phase through a third phase of the CRISPR-Cas immune response: primed spacer acquisition. In this phase, Cas proteins direct the crRNA-guided acquisition of additional spacers to achieve a more rapid and robust immunization of the population.
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Affiliation(s)
- Philip M. Nussenzweig
- Laboratory of Bacteriology, The Rockefeller University, New York, NY 10065, USA
- Weill Cornell/Rockefeller/Sloan Kettering Tri-Institutional MD-PhD Program, New York, NY 10065, USA
| | - Luciano A. Marraffini
- Laboratory of Bacteriology, The Rockefeller University, New York, NY 10065, USA
- Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA
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20
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Zink IA, Wimmer E, Schleper C. Heavily Armed Ancestors: CRISPR Immunity and Applications in Archaea with a Comparative Analysis of CRISPR Types in Sulfolobales. Biomolecules 2020; 10:E1523. [PMID: 33172134 PMCID: PMC7694759 DOI: 10.3390/biom10111523] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 10/31/2020] [Accepted: 11/03/2020] [Indexed: 12/13/2022] Open
Abstract
Prokaryotes are constantly coping with attacks by viruses in their natural environments and therefore have evolved an impressive array of defense systems. Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) is an adaptive immune system found in the majority of archaea and about half of bacteria which stores pieces of infecting viral DNA as spacers in genomic CRISPR arrays to reuse them for specific virus destruction upon a second wave of infection. In detail, small CRISPR RNAs (crRNAs) are transcribed from CRISPR arrays and incorporated into type-specific CRISPR effector complexes which further degrade foreign nucleic acids complementary to the crRNA. This review gives an overview of CRISPR immunity to newcomers in the field and an update on CRISPR literature in archaea by comparing the functional mechanisms and abundances of the diverse CRISPR types. A bigger fraction is dedicated to the versatile and prevalent CRISPR type III systems, as tremendous progress has been made recently using archaeal models in discerning the controlled molecular mechanisms of their unique tripartite mode of action including RNA interference, DNA interference and the unique cyclic-oligoadenylate signaling that induces promiscuous RNA shredding by CARF-domain ribonucleases. The second half of the review spotlights CRISPR in archaea outlining seminal in vivo and in vitro studies in model organisms of the euryarchaeal and crenarchaeal phyla, including the application of CRISPR-Cas for genome editing and gene silencing. In the last section, a special focus is laid on members of the crenarchaeal hyperthermophilic order Sulfolobales by presenting a thorough comparative analysis about the distribution and abundance of CRISPR-Cas systems, including arrays and spacers as well as CRISPR-accessory proteins in all 53 genomes available to date. Interestingly, we find that CRISPR type III and the DNA-degrading CRISPR type I complexes co-exist in more than two thirds of these genomes. Furthermore, we identified ring nuclease candidates in all but two genomes and found that they generally co-exist with the above-mentioned CARF domain ribonucleases Csx1/Csm6. These observations, together with published literature allowed us to draft a working model of how CRISPR-Cas systems and accessory proteins cross talk to establish native CRISPR anti-virus immunity in a Sulfolobales cell.
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21
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Zheng Y, Li J, Wang B, Han J, Hao Y, Wang S, Ma X, Yang S, Ma L, Yi L, Peng W. Endogenous Type I CRISPR-Cas: From Foreign DNA Defense to Prokaryotic Engineering. Front Bioeng Biotechnol 2020; 8:62. [PMID: 32195227 PMCID: PMC7064716 DOI: 10.3389/fbioe.2020.00062] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 01/24/2020] [Indexed: 12/18/2022] Open
Abstract
Establishment of production platforms through prokaryotic engineering in microbial organisms would be one of the most efficient means for chemicals, protein, and biofuels production. Despite the fact that CRISPR (clustered regularly interspaced short palindromic repeats)–based technologies have readily emerged as powerful and versatile tools for genetic manipulations, their applications are generally limited in prokaryotes, possibly owing to the large size and severe cytotoxicity of the heterogeneous Cas (CRISPR-associated) effector. Nevertheless, the rich natural occurrence of CRISPR-Cas systems in many bacteria and most archaea holds great potential for endogenous CRISPR-based prokaryotic engineering. The endogenous CRISPR-Cas systems, with type I systems that constitute the most abundant and diverse group, would be repurposed as genetic manipulation tools once they are identified and characterized as functional in their native hosts. This article reviews the major progress made in understanding the mechanisms of invading DNA immunity by type I CRISPR-Cas and summarizes the practical applications of endogenous type I CRISPR-based toolkits for prokaryotic engineering.
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Affiliation(s)
- Yanli Zheng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Jie Li
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Baiyang Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Jiamei Han
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Yile Hao
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Shengchen Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Xiangdong Ma
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Shihui Yang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Lixin Ma
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Li Yi
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
| | - Wenfang Peng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan, China
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22
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Behler J, Hess WR. Approaches to study CRISPR RNA biogenesis and the key players involved. Methods 2020; 172:12-26. [PMID: 31325492 DOI: 10.1016/j.ymeth.2019.07.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/29/2019] [Accepted: 07/15/2019] [Indexed: 12/26/2022] Open
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) proteins provide an inheritable and adaptive immune system against phages and foreign genetic elements in many bacteria and archaea. The three stages of CRISPR-Cas immunity comprise adaptation, CRISPR RNA (crRNA) biogenesis and interference. The maturation of the pre-crRNA into mature crRNAs, short guide RNAs that target invading nucleic acids, is crucial for the functionality of CRISPR-Cas defense systems. Mature crRNAs assemble with Cas proteins into the ribonucleoprotein (RNP) effector complex and guide the Cas nucleases to the cognate foreign DNA or RNA target. Experimental approaches to characterize these crRNAs, the specific steps toward their maturation and the involved factors, include RNA-seq analyses, enzyme assays, methods such as cryo-electron microscopy, the crystallization of proteins, or UV-induced protein-RNA crosslinking coupled to mass spectrometry analysis. Complex and multiple interactions exist between CRISPR-cas-encoded specific riboendonucleases such as Cas6, Cas5d and Csf5, endonucleases with dual functions in maturation and interference such as the enzymes of the Cas12 and Cas13 families, and nucleases belonging to the cell's degradosome such as RNase E, PNPase and RNase J, both in the maturation as well as in interference. The results of these studies have yielded a picture of unprecedented diversity of sequences, enzymes and biochemical mechanisms.
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Affiliation(s)
- Juliane Behler
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104 Freiburg, Germany
| | - Wolfgang R Hess
- University of Freiburg, Faculty of Biology, Genetics and Experimental Bioinformatics, Schänzlestr. 1, D-79104 Freiburg, Germany; University of Freiburg, Freiburg Institute for Advanced Studies, Albertstr. 19, D-79104 Freiburg, Germany.
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23
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Taylor HN, Warner EE, Armbrust MJ, Crowley VM, Olsen KJ, Jackson RN. Structural basis of Type IV CRISPR RNA biogenesis by a Cas6 endoribonuclease. RNA Biol 2019; 16:1438-1447. [PMID: 31232162 DOI: 10.1080/15476286.2019.1634965] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Prokaryotic CRISPR-Cas adaptive immune systems rely on small non-coding RNAs derived from CRISPR loci to recognize and destroy complementary nucleic acids. However, the mechanism of Type IV CRISPR RNA (crRNA) biogenesis is poorly understood. To dissect the mechanism of Type IV CRISPR RNA biogenesis, we determined the x-ray crystal structure of the putative Type IV CRISPR associated endoribonuclease Cas6 from Mahella australiensis (Ma Cas6-IV) and characterized its enzymatic activity with RNA cleavage assays. We show that Ma Cas6-IV specifically cleaves Type IV crRNA repeats at the 3' side of a predicted stem loop, with a metal-independent, single-turnover mechanism that relies on a histidine and a tyrosine located within the putative endonuclease active site. Structure and sequence alignments with Cas6 orthologs reveal that although Ma Cas6-IV shares little sequence homology with other Cas6 proteins, all share common structural features that bind distinct crRNA repeat sequences. This analysis of Type IV crRNA biogenesis provides a structural and biochemical framework for understanding the similarities and differences of crRNA biogenesis across multi-subunit Class 1 CRISPR immune systems.
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Affiliation(s)
- Hannah N Taylor
- Department of Chemistry and Biochemistry, Utah State University , Logan , UT , USA
| | - Emily E Warner
- Department of Chemistry and Biochemistry, Utah State University , Logan , UT , USA
| | - Matthew J Armbrust
- Department of Chemistry and Biochemistry, Utah State University , Logan , UT , USA
| | - Valerie M Crowley
- Department of Chemistry and Biochemistry, Utah State University , Logan , UT , USA
| | - Keith J Olsen
- Department of Chemistry and Biochemistry, Utah State University , Logan , UT , USA
| | - Ryan N Jackson
- Department of Chemistry and Biochemistry, Utah State University , Logan , UT , USA
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24
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Gong L, Li M, Cheng F, Zhao D, Chen Y, Xiang H. Primed adaptation tolerates extensive structural and size variations of the CRISPR RNA guide in Haloarcula hispanica. Nucleic Acids Res 2019; 47:5880-5891. [PMID: 30957847 PMCID: PMC6582329 DOI: 10.1093/nar/gkz244] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Revised: 03/22/2019] [Accepted: 03/27/2019] [Indexed: 12/13/2022] Open
Abstract
Recent studies on CRISPR adaptation revealed that priming is a major pathway of spacer acquisition, at least for the most prevalent type I systems. Priming is guided by a CRISPR RNA which fully/partially matches the invader DNA, but the plasticity of this RNA guide has not yet been characterized. In this study, we extensively modified the two conserved handles of a priming crRNA in Haloarcula hispanica, and altered the size of its central spacer part. Interestingly, priming is insusceptible to the full deletion of 3' handle, which seriously impaired crRNA stability and interference effects. With 3' handle deletion, further truncation of 5' handle revealed that its spacer-proximal 6 nucleotides could provide the least conserved sequence required for priming. Subsequent scanning mutation further identified critical nucleotides within 5' handle. Besides, priming was also shown to tolerate a wider size variation of the spacer part, compared to interference. These data collectively illustrate the high tolerance of priming to extensive structural/size variations of the crRNA guide, which highlights the structural flexibility of the crRNA-effector ribonucleoprotein complex. The observed high priming effectiveness suggests that primed adaptation promotes clearance of the fast-replicating and ever-evolving viral DNA, by rapidly and persistently multiplexing the interference pathway.
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Affiliation(s)
- Luyao Gong
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ming Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Feiyue Cheng
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Dahe Zhao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yihua Chen
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hua Xiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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25
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Baliga P, Shekar M, Venugopal MN. Detection and characterization of clustered regularly interspaced short palindromic repeat-associated endoribonuclease gene variants in Vibrio parahaemolyticus isolated from seafoods and environment. Vet World 2019; 12:689-695. [PMID: 31327905 PMCID: PMC6584859 DOI: 10.14202/vetworld.2019.689-695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 03/26/2019] [Indexed: 11/17/2022] Open
Abstract
Aim: In Vibrio parahaemolyticus, the clustered regularly interspaced short palindromic repeat (CRISPR)-associated cas6 endoribonuclease gene has been shown to exhibit sequence diversity and has been subtyped into four major types based on its length and composition. In this study, we aimed to detect and characterize the cas6 gene variants prevalent among V. parahaemolyticus strains isolated from seafoods and environment. Materials and Methods: Novel primers were designed for each of the cas6 subtypes to validate their identification in V. parahaemolyticus by polymerase chain reaction (PCR). In total, 38 V. parahaemolyticus strains isolated from seafoods and environment were screened for the presence of cas6 gene. Few representative PCR products were sequenced, and their phylogenetic relationship was established to available cas6 gene sequences in GenBank database. Results: Of the 38 V. parahaemolyticus isolates screened, only about 40% of strains harbored the cas6 endoribonuclease gene, among which 31.6% and 7.9% of the isolates were positive for the presence of the cas6-a and cas6-d subtypes of the gene, respectively. The subtypes cas6-b and cas6-c were absent in strains studied. Sequence and phylogenetic analysis also established the cas6 sequences in this study to match GenBank sequences for cas6-a and cas6-d subtypes. Conclusion: In V. parahaemolyticus, the Cas6 endoribonuclease is an associated protein of the CRISPR-cas system. CRISPR-positive strains exhibited genotypic variation for this gene. Primers designed in this study would aid in identifying the cas6 genotype and understanding the role of these genotypes in the CRISPR-cas immune system of the pathogen.
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Affiliation(s)
- Pallavi Baliga
- Department of Fisheries Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore, Karnataka, India
| | - Malathi Shekar
- Department of Fisheries Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore, Karnataka, India
| | - Moleyur Nagarajappa Venugopal
- Department of Fisheries Microbiology, Karnataka Veterinary, Animal and Fisheries Sciences University, College of Fisheries, Mangalore, Karnataka, India
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Koonin EV, Makarova KS. Origins and evolution of CRISPR-Cas systems. Philos Trans R Soc Lond B Biol Sci 2019; 374:20180087. [PMID: 30905284 PMCID: PMC6452270 DOI: 10.1098/rstb.2018.0087] [Citation(s) in RCA: 203] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2018] [Indexed: 12/11/2022] Open
Abstract
CRISPR-Cas, the bacterial and archaeal adaptive immunity systems, encompass a complex machinery that integrates fragments of foreign nucleic acids, mostly from mobile genetic elements (MGE), into CRISPR arrays embedded in microbial genomes. Transcripts of the inserted segments (spacers) are employed by CRISPR-Cas systems as guide (g)RNAs for recognition and inactivation of the cognate targets. The CRISPR-Cas systems consist of distinct adaptation and effector modules whose evolutionary trajectories appear to be at least partially independent. Comparative genome analysis reveals the origin of the adaptation module from casposons, a distinct type of transposons, which employ a homologue of Cas1 protein, the integrase responsible for the spacer incorporation into CRISPR arrays, as the transposase. The origin of the effector module(s) is far less clear. The CRISPR-Cas systems are partitioned into two classes, class 1 with multisubunit effectors, and class 2 in which the effector consists of a single, large protein. The class 2 effectors originate from nucleases encoded by different MGE, whereas the origin of the class 1 effector complexes remains murky. However, the recent discovery of a signalling pathway built into the type III systems of class 1 might offer a clue, suggesting that type III effector modules could have evolved from a signal transduction system involved in stress-induced programmed cell death. The subsequent evolution of the class 1 effector complexes through serial gene duplication and displacement, primarily of genes for proteins containing RNA recognition motif domains, can be hypothetically reconstructed. In addition to the multiple contributions of MGE to the evolution of CRISPR-Cas, the reverse flow of information is notable, namely, recruitment of minimalist variants of CRISPR-Cas systems by MGE for functions that remain to be elucidated. Here, we attempt a synthesis of the diverse threads that shed light on CRISPR-Cas origins and evolution. This article is part of a discussion meeting issue 'The ecology and evolution of prokaryotic CRISPR-Cas adaptive immune systems'.
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Affiliation(s)
- Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
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27
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Dorsey BW, Huang L, Mondragón A. Structural organization of a Type III-A CRISPR effector subcomplex determined by X-ray crystallography and cryo-EM. Nucleic Acids Res 2019; 47:3765-3783. [PMID: 30759237 PMCID: PMC6468305 DOI: 10.1093/nar/gkz079] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/28/2019] [Accepted: 01/30/2019] [Indexed: 02/06/2023] Open
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR) and their associated Cas proteins provide an immune-like response in many prokaryotes against extraneous nucleic acids. CRISPR-Cas systems are classified into different classes and types. Class 1 CRISPR-Cas systems form multi-protein effector complexes that includes a guide RNA (crRNA) used to identify the target for destruction. Here we present crystal structures of Staphylococcus epidermidis Type III-A CRISPR subunits Csm2 and Csm3 and a 5.2 Å resolution single-particle cryo-electron microscopy (cryo-EM) reconstruction of an in vivo assembled effector subcomplex including the crRNA. The structures help to clarify the quaternary architecture of Type III-A effector complexes, and provide details on crRNA binding, target RNA binding and cleavage, and intermolecular interactions essential for effector complex assembly. The structures allow a better understanding of the organization of Type III-A CRISPR effector complexes as well as highlighting the overall similarities and differences with other Class 1 effector complexes.
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Affiliation(s)
- Bryan W Dorsey
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
| | - Lei Huang
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
| | - Alfonso Mondragón
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208, USA
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28
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Molecular mechanisms of III-B CRISPR–Cas systems in archaea. Emerg Top Life Sci 2018; 2:483-491. [DOI: 10.1042/etls20180023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 08/26/2018] [Accepted: 08/31/2018] [Indexed: 12/26/2022]
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) systems provide the adaptive antiviral immunity against invasive genetic elements in archaea and bacteria. These immune systems are divided into at least six different types, among which Type III CRISPR–Cas systems show several distinct antiviral activities as demonstrated from the investigation of bacterial III-A and archaeal III-B systems in the past decade. First, although initial experiments suggested that III-A systems provided DNA interference activity, whereas III-B system was active only in RNA interference, these immune systems were subsequently found to mediate the transcription-dependent DNA interference and the dual DNA/RNA interference. Second, their ribonucleoprotein (RNP) complexes show target RNA (tgRNA) cleavage by a ruler mechanism and RNA-activated indiscriminate single-stranded DNA cleavage, the latter of which is subjected to spatiotemporal regulation such that the DNase activity occurs only at the right place in the right time. Third, RNPs of Type III systems catalyse the synthesis of cyclic oligoadenylates (cOAs) that function as second messengers to activate Csm6 and Csx1, both of which are potent Cas accessory RNases after activation. To date, Type III CRISPR systems are the only known antiviral immunity that utilizes multiple interference mechanisms for antiviral defence.
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29
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Majumdar S, Terns MP. CRISPR RNA-guided DNA cleavage by reconstituted Type I-A immune effector complexes. Extremophiles 2018; 23:19-33. [PMID: 30284045 DOI: 10.1007/s00792-018-1057-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 09/24/2018] [Indexed: 12/16/2022]
Abstract
Diverse CRISPR-Cas immune systems protect archaea and bacteria from viruses and other mobile genetic elements. All CRISPR-Cas systems ultimately function by sequence-specific destruction of invading complementary nucleic acids. However, each CRISPR system uses compositionally distinct crRNP [CRISPR (cr) RNA/Cas protein] immune effector complexes to recognize and destroy invasive nucleic acids by unique molecular mechanisms. Previously, we found that Type I-A (Csa) effector crRNPs from Pyrococcus furiosus function in vivo to eliminate invader DNA. Here, we reconstituted functional Type I-A effector crRNPs in vitro with recombinant Csa proteins and synthetic crRNA and characterized properties of crRNP assembly, target DNA recognition and cleavage. Six proteins (Csa 4-1, Cas3″, Cas3', Cas5a, Csa2, Csa5) are essential for selective target DNA binding and cleavage. Native gel shift analysis and UV-induced RNA-protein crosslinking demonstrate that Cas5a and Csa2 directly interact with crRNA 5' tag and guide sequences, respectively. Mutational analysis revealed that Cas3″ is the effector nuclease of the complex. Together, our results indicate that DNA cleavage by Type I-A crRNPs requires crRNA-guided and protospacer adjacent motif-dependent target DNA binding to unwind double-stranded DNA and expose single strands for progressive ATP-dependent 3'-5' cleavage catalyzed by integral Cas3' helicase and Cas3″ nuclease crRNP components.
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Affiliation(s)
- Sonali Majumdar
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Michael P Terns
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA. .,Department of Genetics, University of Georgia, Athens, GA, 30602, USA. .,Department of Microbiology, University of Georgia, Athens, GA, 30602, USA.
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30
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Wei W, Zhang S, Fleming J, Chen Y, Li Z, Fan S, Liu Y, Wang W, Wang T, Liu Y, Ren B, Wang M, Jiao J, Chen Y, Zhou Y, Zhou Y, Gu S, Zhang X, Wan L, Chen T, Zhou L, Chen Y, Zhang XE, Li C, Zhang H, Bi L. Mycobacterium tuberculosis type III-A CRISPR/Cas system crRNA and its maturation have atypical features. FASEB J 2018; 33:1496-1509. [PMID: 29979631 DOI: 10.1096/fj.201800557rr] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) systems are prokaryotic adaptive immune systems against invading nucleic acids. CRISPR locus variability has been exploited in evolutionary and epidemiological studies of Mycobacterium tuberculosis, the causative agent of tuberculosis, for over 20 yr, yet the biological function of this type III-A system is largely unexplored. Here, using cell biology and biochemical, mutagenic, and RNA-seq approaches, we show it is active in invader defense and has features atypical of type III-A systems: mature CRISPR RNA (crRNA) in its crRNA-CRISPR/Cas protein complex are of uniform length (∼71 nt) and appear not to be subject to 3'-end processing after Cas6 cleavage of repeat RNA 8 nt from its 3' end. crRNAs generated resemble mature crRNA in type I systems, having both 5' (8 nt) and 3' (28 nt) repeat tags. Cas6 cleavage of repeat RNA is ion dependent, and accurate cleavage depends on the presence of a 3' hairpin in the repeat RNA and the sequence of its stem base nucleotides. This study unveils further diversity among CRISPR/Cas systems and provides insight into the crRNA recognition mechanism in M. tuberculosis, providing a foundation for investigating the potential of a type III-A-based genome editing system.-Wei, W., Zhang, S., Fleming, J., Chen, Y., Li, Z., Fan, S., Liu, Y., Wang, W., Wang, T., Liu, Y., Ren, B., Wang, M., Jiao, J., Chen, Y., Zhou, Y., Zhou, Y., Gu, S., Zhang, X., Wan, L., Chen, T., Zhou, L., Chen, Y., Zhang, X.-E., Li, C., Zhang, H., Bi, L. Mycobacterium tuberculosis type III-A CRISPR/Cas system crRNA and its maturation have atypical features.
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Affiliation(s)
- Wenjing Wei
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of the Chinese Academy of Sciences, Beijing, China
| | - Shuai Zhang
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of the Chinese Academy of Sciences, Beijing, China
| | - Joy Fleming
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,School of Stomatology and Medicine, Foshan University, Foshan, China
| | - Ying Chen
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Zihui Li
- Beijing Chest Hospital, Capital Medical University, Beijing, China
| | - Shanghua Fan
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yi Liu
- Beijing Chest Hospital, Capital Medical University, Beijing, China
| | - Wei Wang
- Beijing Chest Hospital, Capital Medical University, Beijing, China
| | - Ting Wang
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Ying Liu
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Baiguang Ren
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Ming Wang
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Jianjian Jiao
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yuanyuan Chen
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Ying Zhou
- School of Stomatology and Medicine, Foshan University, Foshan, China
| | - Yafeng Zhou
- School of Stomatology and Medicine, Foshan University, Foshan, China
| | - Shoujin Gu
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,School of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai, China
| | - Xiaoli Zhang
- School of Stomatology and Medicine, Foshan University, Foshan, China
| | - Li Wan
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Tao Chen
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China; and
| | - Lin Zhou
- Center for Tuberculosis Control of Guangdong Province, Guangzhou, China; and
| | - Yong Chen
- School of Stomatology and Medicine, Foshan University, Foshan, China
| | - Xian-En Zhang
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,School of Stomatology and Medicine, Foshan University, Foshan, China
| | - Chuanyou Li
- Beijing Chest Hospital, Capital Medical University, Beijing, China
| | - Hongtai Zhang
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Lijun Bi
- Key Laboratory of RNA Biology and National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,School of Stomatology and Medicine, Foshan University, Foshan, China.,Guangdong Province Key Laboratory of Tuberculosis Systems Biology and Translational Medicine, Foshan, China
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31
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Maier LK, Stachler AE, Brendel J, Stoll B, Fischer S, Haas KA, Schwarz TS, Alkhnbashi OS, Sharma K, Urlaub H, Backofen R, Gophna U, Marchfelder A. The nuts and bolts of the Haloferax CRISPR-Cas system I-B. RNA Biol 2018; 16:469-480. [PMID: 29649958 PMCID: PMC6546412 DOI: 10.1080/15476286.2018.1460994] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Invading genetic elements pose a constant threat to prokaryotic survival, requiring an effective defence. Eleven years ago, the arsenal of known defence mechanisms was expanded by the discovery of the CRISPR-Cas system. Although CRISPR-Cas is present in the majority of archaea, research often focuses on bacterial models. Here, we provide a perspective based on insights gained studying CRISPR-Cas system I-B of the archaeon Haloferax volcanii. The system relies on more than 50 different crRNAs, whose stability and maintenance critically depend on the proteins Cas5 and Cas7, which bind the crRNA and form the Cascade complex. The interference machinery requires a seed sequence and can interact with multiple PAM sequences. H. volcanii stands out as the first example of an organism that can tolerate autoimmunity via the CRISPR-Cas system while maintaining a constitutively active system. In addition, the H. volcanii system was successfully developed into a tool for gene regulation.
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Affiliation(s)
| | | | | | | | | | - Karina A Haas
- a Biology II, Ulm University , Ulm , Germany.,b Microbiology and Biotechnology, Ulm University , Ulm , Germany
| | | | - Omer S Alkhnbashi
- c Freiburg Bioinformatics Group, Department of Computer Science , University of Freiburg , Georges-Köhler-Allee 106, Freiburg , Germany
| | - Kundan Sharma
- e Max Planck Institute of Biophysical Chemistry , Am Faßberg 11, Göttingen , Germany.,f Ludwig Institute for Cancer Research, University of Oxford , Oxford , United Kingdom
| | - Henning Urlaub
- e Max Planck Institute of Biophysical Chemistry , Am Faßberg 11, Göttingen , Germany.,g Institute for Clinical Chemistry, University Medical Center Göttingen , Robert Koch Straße 10, Göttingen , Germany
| | - Rolf Backofen
- c Freiburg Bioinformatics Group, Department of Computer Science , University of Freiburg , Georges-Köhler-Allee 106, Freiburg , Germany.,d Centre for Biological Signalling Studies (BIOSS), Cluster of Excellence, University of Freiburg , Germany
| | - Uri Gophna
- h School of Molecular Cell Biology & Biotechnology, George S. Wise, Faculty of Life Sciences, Tel Aviv University , Tel Aviv , Israel
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32
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Hille F, Richter H, Wong SP, Bratovič M, Ressel S, Charpentier E. The Biology of CRISPR-Cas: Backward and Forward. Cell 2018. [DOI: 10.1016/j.cell.2017.11.032] [Citation(s) in RCA: 333] [Impact Index Per Article: 55.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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33
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Uppada V, Gokara M, Rasineni GK. Diagnosis and therapy with CRISPR advanced CRISPR based tools for point of care diagnostics and early therapies. Gene 2018; 656:22-29. [PMID: 29496558 DOI: 10.1016/j.gene.2018.02.066] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 02/14/2018] [Accepted: 02/24/2018] [Indexed: 12/26/2022]
Abstract
Molecular diagnostics is of critical importance to public health worldwide. It facilitates not only detection and characterization of diseases, but also monitors drug responses, assists in the identification of genetic modifiers and disease susceptibility. Based upon DNA variation, a wide range of molecular-based tests are available to assess/diagnose diseases. The CRISPR-Cas9 system has recently emerged as a versatile tool for biological and medical research. In this system, a single guide RNA (sgRNA) directs the endonuclease Cas9 to a targeted DNA sequence for site-specific manipulation. As designing CRISPR-guided nucleases can be done easily and relatively fast, the CRISPR/Cas9 system has evolved as widely used DNA editing tool. This technique led to a large number of gene editing studies in variety of organisms. CRISPR/Cas9-mediated diagnosis and therapy has picked up pace due to specificity and accuracy of CRISPR. The aim is not only to identify specific pathogens, especially virus but also to repair disease-causing alleles by changing the DNA sequence at the exact location on the chromosome. At present, PCR-based molecular diagnostic testing predominates; however, alternative technologies aimed at reducing genome complexity without PCR are anticipated to gain momentum in the coming years. Furthermore, development of integrated chip devices should allow point-of-care testing and facilitate genetic readouts from single cells and molecules. Together with molecular based therapy CRISPR based diagnostic testing will be a revolution in modern health care settings. In this review, we emphasize on current developing diagnostic techniques based upon CRISPR Cas approach along with short insights on its therapeutic usage.
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Affiliation(s)
- Vanita Uppada
- Department of Animal Biology, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - Mahesh Gokara
- Department of Biochemistry, University of Hyderabad, Hyderabad 500046, Telangana, India
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34
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Silas S, Jain N, Stadler M, Fu BXH, Sánchez-Amat A, Fire AZ, Arribere J. A Small RNA Isolation and Sequencing Protocol and Its Application to Assay CRISPR RNA Biogenesis in Bacteria. Bio Protoc 2018; 8:e2727. [PMID: 29600253 PMCID: PMC5870890 DOI: 10.21769/bioprotoc.2727] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Revised: 01/23/2018] [Accepted: 01/29/2018] [Indexed: 11/02/2022] Open
Abstract
Next generation high-throughput sequencing has enabled sensitive and unambiguous analysis of RNA populations in cells. Here, we describe a method for isolation and strand-specific sequencing of small RNA pools from bacteria that can be multiplexed to accommodate multiple biological samples in a single experiment. Small RNAs are isolated by polyacrylamide gel electrophoresis and treated with T4 polynucleotide kinase. This allows for 3' adapter ligation to CRISPR RNAs, which don't have pre-existing 3'-OH ends. Pre-adenylated adapters are then ligated using T4 RNA ligase 1 in the absence of ATP and with a high concentration of polyethylene glycol (PEG). The 3' capture step enables precise determination of the 3' ends of diverse RNA molecules. Additionally, a random hexamer in the ligated adapter helps control for potential downstream amplification bias. Following reverse-transcription, the cDNA product is circularized and libraries are prepared by PCR. We show that the amplified library need not be visible by gel electrophoresis for efficient sequencing of the desired product. Using this method, we routinely prepare RNA sequencing libraries from minute amounts of purified small RNA. This protocol is tailored to assay for CRISPR RNA biogenesis in bacteria through sequencing of mature CRISPR RNAs, but can be used to sequence diverse classes of small RNAs. We also provide a fully worked example of our data processing pipeline, with instructions for running the provided scripts.
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Affiliation(s)
- Sukrit Silas
- Department of Pathology, Stanford University, Stanford, CA, USA
- Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Nimit Jain
- Department of Pathology, Stanford University, Stanford, CA, USA
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Michael Stadler
- Department of Pathology, Stanford University, Stanford, CA, USA
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Becky Xu Hua Fu
- Department of Pathology, Stanford University, Stanford, CA, USA
| | | | - Andrew Z. Fire
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - Joshua Arribere
- Department of Pathology, Stanford University, Stanford, CA, USA
- Department of MCD Biology, University of California, Santa Cruz, CA, USA
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35
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The host-encoded RNase E endonuclease as the crRNA maturation enzyme in a CRISPR-Cas subtype III-Bv system. Nat Microbiol 2018; 3:367-377. [PMID: 29403013 DOI: 10.1038/s41564-017-0103-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 12/20/2017] [Indexed: 02/08/2023]
Abstract
Specialized RNA endonucleases for the maturation of clustered regularly interspaced short palindromic repeat (CRISPR)-derived RNAs (crRNAs) are critical in CRISPR-CRISPR-associated protein (Cas) defence mechanisms. The Cas6 and Cas5d enzymes are the RNA endonucleases in many class 1 CRISPR-Cas systems. In some class 2 systems, maturation and effector functions are combined within a single enzyme or maturation proceeds through the combined actions of RNase III and trans-activating CRISPR RNAs (tracrRNAs). Three separate CRISPR-Cas systems exist in the cyanobacterium Synechocystis sp. PCC 6803. Whereas Cas6-type enzymes act in two of these systems, the third, which is classified as subtype III-B variant (III-Bv), lacks cas6 homologues. Instead, the maturation of crRNAs proceeds through the activity of endoribonuclease E, leaving unusual 13- and 14-nucleotide-long 5'-handles. Overexpression of RNase E leads to overaccumulation and knock-down to the reduced accumulation of crRNAs in vivo, suggesting that RNase E is the limiting factor for CRISPR complex formation. Recognition by RNase E depends on a stem-loop in the CRISPR repeat, whereas base substitutions at the cleavage site trigger the appearance of secondary products, consistent with a two-step recognition and cleavage mechanism. These results suggest the adaptation of an otherwise very conserved housekeeping enzyme to accommodate new substrates and illuminate the impressive plasticity of CRISPR-Cas systems that enables them to function in particular genomic environments.
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36
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Leon LM, Mendoza SD, Bondy-Denomy J. How bacteria control the CRISPR-Cas arsenal. Curr Opin Microbiol 2017; 42:87-95. [PMID: 29169146 DOI: 10.1016/j.mib.2017.11.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 10/30/2017] [Accepted: 11/03/2017] [Indexed: 02/07/2023]
Abstract
CRISPR-Cas systems are adaptive immune systems that protect their hosts from predation by bacteriophages (phages) and parasitism by other mobile genetic elements (MGEs). Given the potent nuclease activity of CRISPR effectors, these enzymes must be carefully regulated to minimize toxicity and maximize anti-phage immunity. While attention has been given to the transcriptional regulation of these systems (reviewed in [1]), less consideration has been given to the crucial post-translational processes that govern enzyme activation and inactivation. Here, we review recent findings that describe how Cas nucleases are controlled in diverse systems to provide a robust anti-viral response while limiting auto-immunity. We also draw comparisons to a distinct bacterial immune system, restriction-modification.
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Affiliation(s)
- Lina M Leon
- Department of Microbiology & Immunology, University of California, San Francisco, United States
| | - Senén D Mendoza
- Department of Microbiology & Immunology, University of California, San Francisco, United States
| | - Joseph Bondy-Denomy
- Department of Microbiology & Immunology, University of California, San Francisco, United States; Quantitative Biosciences Institute, University of California, San Francisco, United States.
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37
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Cheng F, Gong L, Zhao D, Yang H, Zhou J, Li M, Xiang H. Harnessing the native type I-B CRISPR-Cas for genome editing in a polyploid archaeon. J Genet Genomics 2017; 44:541-548. [DOI: 10.1016/j.jgg.2017.09.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 09/18/2017] [Accepted: 09/25/2017] [Indexed: 12/26/2022]
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38
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Li M, Gong L, Zhao D, Zhou J, Xiang H. The spacer size of I-B CRISPR is modulated by the terminal sequence of the protospacer. Nucleic Acids Res 2017; 45:4642-4654. [PMID: 28379481 PMCID: PMC5416893 DOI: 10.1093/nar/gkx229] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/25/2017] [Indexed: 12/29/2022] Open
Abstract
Prokaryotes memorize invader information by incorporating alien DNA as spacers into CRISPR arrays. Although the spacer size has been suggested to be predefined by the architecture of the acquisition complex, there is usually an unexpected heterogeneity. Here, we explored the causes of this heterogeneity in Haloarcula hispanica I-B CRISPR. High-throughput sequencing following adaptation assays demonstrated significant size variation among 37 957 new spacers, which appeared to be sequence-dependent. Consistently, the third nucleotide at the spacer 3΄-end (PAM-distal end) showed an evident bias for cytosine and mutating this cytosine in the protospacer sequence could change the final spacer size. In addition, slippage of the 5΄-end (PAM-end), which contributed to most of the observed PAM (protospacer adjacent motif) inaccuracy, also tended to change the spacer size. We propose that both ends of the PAM-protospacer sequence should exhibit nucleotide selectivity (with different stringencies), which fine-tunes the structural ruler, to a certain extent, to specify the spacer size.
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Affiliation(s)
- Ming Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Luyao Gong
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dahe Zhao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jian Zhou
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Hua Xiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing 100049, China
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39
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Sefcikova J, Roth M, Yu G, Li H. Cas6 processes tight and relaxed repeat RNA via multiple mechanisms: A hypothesis. Bioessays 2017; 39. [PMID: 28493337 DOI: 10.1002/bies.201700019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
RNA molecules are flexible yet foldable. Proteins must cope with this structural duality when forming biologically active complexes with RNA. Recent studies of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs)-mediated RNA immunity illustrate some remarkable mechanisms with which proteins interact with RNA. Currently known structures of CRISPR-Cas6 endoribonucleases bound with RNA suggest a conserved protein recognition mechanism mediated by RNA stem-loops. However, a survey of CRISPR RNA reveals that many repeats either lack a productive stem-loop (Relaxed) or possess stable but inhibitory structures (Tight), which raises the question of how the enzyme processes structurally diverse RNA. In reviewing recent literature, we propose a bivalent trapping and an unwinding mechanism for CRISPR-Cas6 to interact with the Relaxed and the Tight repeat RNA, respectively. Both mechanisms aim to create an identical RNA conformation at the cleavage site for accurate processing.
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Affiliation(s)
- Jana Sefcikova
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA
| | - Mitchell Roth
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Ge Yu
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
| | - Hong Li
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA.,Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL, USA
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40
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Liu TY, Iavarone AT, Doudna JA. RNA and DNA Targeting by a Reconstituted Thermus thermophilus Type III-A CRISPR-Cas System. PLoS One 2017; 12:e0170552. [PMID: 28114398 PMCID: PMC5256923 DOI: 10.1371/journal.pone.0170552] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Accepted: 01/07/2017] [Indexed: 12/26/2022] Open
Abstract
CRISPR-Cas (clustered regularly interspaced short palindromic repeats-CRISPR-associated) systems are RNA-guided adaptive immunity pathways used by bacteria and archaea to defend against phages and plasmids. Type III-A systems use a multisubunit interference complex called Csm, containing Cas proteins and a CRISPR RNA (crRNA) to target cognate nucleic acids. The Csm complex is intriguing in that it mediates RNA-guided targeting of both RNA and transcriptionally active DNA, but the mechanism is not well understood. Here, we overexpressed the five components of the Thermus thermophilus (T. thermophilus) Type III-A Csm complex (TthCsm) with a defined crRNA sequence, and purified intact TthCsm complexes from E. coli cells. The complexes were thermophilic, targeting complementary ssRNA more efficiently at 65°C than at 37°C. Sequence-independent, endonucleolytic cleavage of single-stranded DNA (ssDNA) by TthCsm was triggered by recognition of a complementary ssRNA, and required a lack of complementarity between the first 8 nucleotides (5′ tag) of the crRNA and the 3′ flanking region of the ssRNA. Mutation of the histidine-aspartate (HD) nuclease domain of the TthCsm subunit, Cas10/Csm1, abolished DNA cleavage. Activation of DNA cleavage was dependent on RNA binding but not cleavage. This leads to a model in which binding of an ssRNA target to the Csm complex would stimulate cleavage of exposed ssDNA in the cell, such as could occur when the RNA polymerase unwinds double-stranded DNA (dsDNA) during transcription. Our findings establish an amenable, thermostable system for more in-depth investigation of the targeting mechanism using structural biology methods, such as cryo-electron microscopy and x-ray crystallography.
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Affiliation(s)
- Tina Y. Liu
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
- Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
| | - Anthony T. Iavarone
- Department of Chemistry, University of California, Berkeley, California, United States of America
| | - Jennifer A. Doudna
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
- Howard Hughes Medical Institute, University of California, Berkeley, California, United States of America
- Innovative Genomics Initiative, University of California, Berkeley, California, United States of America
- MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
- California Institute for Quantitative Biosciences, University of California, Berkeley, California, United States of America
- * E-mail:
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41
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Abstract
Prokaryotes use diverse strategies to improve fitness in the face of different environmental threats and stresses, including those posed by mobile genetic elements (e.g., bacteriophages and plasmids). To defend against these elements, many bacteria and archaea use elegant, RNA-directed, nucleic acid-targeting adaptive restriction machineries called CRISPR -: Cas (CRISPR-associated) systems. While providing an effective defense against foreign genetic elements, these systems have also been observed to play critical roles in regulating bacterial physiology during environmental stress. Increasingly, CRISPR-Cas systems, in particular the Type II systems containing the Cas9 endonuclease, have been exploited for their ability to bind desired nucleic acid sequences, as well as direct sequence-specific cleavage of their targets. Cas9-mediated genome engineering is transcending biological research as a versatile and portable platform for manipulating genetic content in myriad systems. Here, we present a systematic overview of CRISPR-Cas history and biology, highlighting the revolutionary tools derived from these systems, which greatly expand the molecular biologists' toolkit.
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Affiliation(s)
- Hannah K Ratner
- Department of Microbiology and Immunology, Microbiology and Molecular Genetics Program, Emory University, Atlanta, Georgia 30329
- Emory Vaccine Center, Emory University, Atlanta, Georgia 30329
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
| | - Timothy R Sampson
- Department of Microbiology and Immunology, Microbiology and Molecular Genetics Program, Emory University, Atlanta, Georgia 30329
- Emory Vaccine Center, Emory University, Atlanta, Georgia 30329
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
| | - David S Weiss
- Emory Vaccine Center, Emory University, Atlanta, Georgia 30329
- Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30329
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42
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Kuznedelov K, Mekler V, Lemak S, Tokmina-Lukaszewska M, Datsenko KA, Jain I, Savitskaya E, Mallon J, Shmakov S, Bothner B, Bailey S, Yakunin AF, Severinov K, Semenova E. Altered stoichiometry Escherichia coli Cascade complexes with shortened CRISPR RNA spacers are capable of interference and primed adaptation. Nucleic Acids Res 2016; 44:10849-10861. [PMID: 27738137 PMCID: PMC5159557 DOI: 10.1093/nar/gkw914] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 09/29/2016] [Accepted: 10/03/2016] [Indexed: 12/26/2022] Open
Abstract
The Escherichia coli type I-E CRISPR-Cas system Cascade effector is a multisubunit complex that binds CRISPR RNA (crRNA). Through its 32-nucleotide spacer sequence, Cascade-bound crRNA recognizes protospacers in foreign DNA, causing its destruction during CRISPR interference or acquisition of additional spacers in CRISPR array during primed CRISPR adaptation. Within Cascade, the crRNA spacer interacts with a hexamer of Cas7 subunits. We show that crRNAs with a spacer length reduced to 14 nucleotides cause primed adaptation, while crRNAs with spacer lengths of more than 20 nucleotides cause both primed adaptation and target interference in vivo. Shortened crRNAs assemble into altered-stoichiometry Cascade effector complexes containing less than the normal amount of Cas7 subunits. The results show that Cascade assembly is driven by crRNA and suggest that multisubunit type I CRISPR effectors may have evolved from much simpler ancestral complexes.
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Affiliation(s)
- Konstantin Kuznedelov
- Waksman Institute of Microbiology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Vladimir Mekler
- Waksman Institute of Microbiology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Sofia Lemak
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | | | - Kirill A Datsenko
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Ishita Jain
- Waksman Institute of Microbiology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
| | - Ekaterina Savitskaya
- Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Institute of Molecular Genetics, Russian Academy of Sciences, Moscow 123182, Russia
| | - John Mallon
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Sergey Shmakov
- Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,NCBI, NLM, NIH, Bethesda, MD 20894, USA
| | - Brian Bothner
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - Scott Bailey
- Department of Biochemistry and Molecular Biology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Alexander F Yakunin
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Konstantin Severinov
- Waksman Institute of Microbiology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA .,Skolkovo Institute of Science and Technology, Skolkovo 143025, Russia.,Institute of Molecular Genetics, Russian Academy of Sciences, Moscow 123182, Russia.,Peter the Great St Petersburg State Polytechnic University, St. Petersburg, 195251, Russia
| | - Ekaterina Semenova
- Waksman Institute of Microbiology, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA
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43
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Target DNA recognition and cleavage by a reconstituted Type I-G CRISPR-Cas immune effector complex. Extremophiles 2016; 21:95-107. [PMID: 27582008 DOI: 10.1007/s00792-016-0871-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 08/16/2016] [Indexed: 12/26/2022]
Abstract
CRISPR-Cas immune systems defend prokaryotes against viruses and plasmids. CRISPR RNAs (crRNAs) associate with various CRISPR-associated (Cas) protein modules to form structurally and functionally diverse (Type I-VI) crRNP immune effector complexes. Previously, we identified three, co-existing effector complexes in Pyrococcus furiosus -Type I-A (Csa), Type I-G (Cst), and Type III-B (Cmr)-and demonstrated that each complex functions in vivo to eliminate invader DNA. Here, we reconstitute functional Cst crRNP complexes in vitro from recombinant Cas proteins and synthetic crRNAs and investigate mechanisms of crRNP assembly and invader DNA recognition and destruction. All four known Cst-affiliated Cas proteins (Cas5t, Cst1, Cst2, and Cas3) are required for activity, but each subunit plays a distinct role. Cas5t and Cst2 comprise a minimal set of proteins that selectively interact with crRNA. Further addition of Cst1, enables the four subunit crRNP (Cas5t, Cst1, Cst2, crRNA) to specifically bind complementary, double-stranded DNA targets and to recruit the Cas3 effector nuclease, which catalyzes cleavages at specific sites within the displaced, non-target DNA strand. Our results indicate that Type I-G crRNPs selectively bind target DNA in a crRNA and, protospacer adjacent motif dependent manner to recruit a dedicated Cas3 nuclease for invader DNA destruction.
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44
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Gleditzsch D, Müller-Esparza H, Pausch P, Sharma K, Dwarakanath S, Urlaub H, Bange G, Randau L. Modulating the Cascade architecture of a minimal Type I-F CRISPR-Cas system. Nucleic Acids Res 2016; 44:5872-82. [PMID: 27216815 PMCID: PMC4937334 DOI: 10.1093/nar/gkw469] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/13/2016] [Indexed: 12/26/2022] Open
Abstract
Shewanella putrefaciens CN-32 contains a single Type I-Fv CRISPR-Cas system which confers adaptive immunity against bacteriophage infection. Three Cas proteins (Cas6f, Cas7fv, Cas5fv) and mature CRISPR RNAs were shown to be required for the assembly of an interference complex termed Cascade. The Cas protein-CRISPR RNA interaction sites within this complex were identified via mass spectrometry. Additional Cas proteins, commonly described as large and small subunits, that are present in all other investigated Cascade structures, were not detected. We introduced this minimal Type I system in Escherichia coli and show that it provides heterologous protection against lambda phage. The absence of a large subunit suggests that the length of the crRNA might not be fixed and recombinant Cascade complexes with drastically shortened and elongated crRNAs were engineered. Size-exclusion chromatography and small-angle X-ray scattering analyses revealed that the number of Cas7fv backbone subunits is adjusted in these shortened and extended Cascade variants. Larger Cascade complexes can still confer immunity against lambda phage infection in E. coli. Minimized Type I CRISPR-Cas systems expand our understanding of the evolution of Cascade assembly and diversity. Their adjustable crRNA length opens the possibility for customizing target DNA specificity.
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Affiliation(s)
- Daniel Gleditzsch
- Prokaryotic Small RNA Biology Group, Max Planck Institute for Terrestrial Microbiology, D-35043 Marburg, Germany
| | - Hanna Müller-Esparza
- Prokaryotic Small RNA Biology Group, Max Planck Institute for Terrestrial Microbiology, D-35043 Marburg, Germany
| | - Patrick Pausch
- LOEWE Center for Synthetic Microbiology, Philipps University Marburg, D-35043 Marburg, Germany Department of Chemistry, Philipps University Marburg, D-35043 Marburg, Germany
| | - Kundan Sharma
- Bioanalytics Research Group, Department of Clinical Chemistry, University Medical Centre, D-37075 Göttingen, Germany
| | - Srivatsa Dwarakanath
- Prokaryotic Small RNA Biology Group, Max Planck Institute for Terrestrial Microbiology, D-35043 Marburg, Germany
| | - Henning Urlaub
- Bioanalytics Research Group, Department of Clinical Chemistry, University Medical Centre, D-37075 Göttingen, Germany Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, D-37077 Göttingen, Germany
| | - Gert Bange
- LOEWE Center for Synthetic Microbiology, Philipps University Marburg, D-35043 Marburg, Germany Department of Chemistry, Philipps University Marburg, D-35043 Marburg, Germany
| | - Lennart Randau
- Prokaryotic Small RNA Biology Group, Max Planck Institute for Terrestrial Microbiology, D-35043 Marburg, Germany LOEWE Center for Synthetic Microbiology, Philipps University Marburg, D-35043 Marburg, Germany
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45
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Wang R, Li M, Gong L, Hu S, Xiang H. DNA motifs determining the accuracy of repeat duplication during CRISPR adaptation in Haloarcula hispanica. Nucleic Acids Res 2016; 44:4266-77. [PMID: 27085805 PMCID: PMC4872114 DOI: 10.1093/nar/gkw260] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 04/01/2016] [Indexed: 01/26/2023] Open
Abstract
Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) acquire new spacers to generate adaptive immunity in prokaryotes. During spacer integration, the leader-preceded repeat is always accurately duplicated, leading to speculations of a repeat-length ruler. Here in Haloarcula hispanica, we demonstrate that the accurate duplication of its 30-bp repeat requires two conserved mid-repeat motifs, AACCC and GTGGG. The AACCC motif was essential and needed to be ∼10 bp downstream from the leader-repeat junction site, where duplication consistently started. Interestingly, repeat duplication terminated sequence-independently and usually with a specific distance from the GTGGG motif, which seemingly served as an anchor site for a molecular ruler. Accordingly, altering the spacing between the two motifs led to an aberrant duplication size (29, 31, 32 or 33 bp). We propose the adaptation complex may recognize these mid-repeat elements to enable measuring the repeat DNA for spacer integration.
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Affiliation(s)
- Rui Wang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ming Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Luyao Gong
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Songnian Hu
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Hua Xiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
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46
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Elmore J, Deighan T, Westpheling J, Terns RM, Terns MP. DNA targeting by the type I-G and type I-A CRISPR-Cas systems of Pyrococcus furiosus. Nucleic Acids Res 2015; 43:10353-63. [PMID: 26519471 PMCID: PMC4666368 DOI: 10.1093/nar/gkv1140] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 10/16/2015] [Indexed: 12/26/2022] Open
Abstract
CRISPR–Cas systems silence plasmids and viruses in prokaryotes. CRISPR–Cas effector complexes contain CRISPR RNAs (crRNAs) that include sequences captured from invaders and direct CRISPR-associated (Cas) proteins to destroy corresponding invader nucleic acids. Pyrococcus furiosus (Pfu) harbors three CRISPR–Cas immune systems: a Cst (Type I-G) system with an associated Cmr (Type III-B) module at one locus, and a partial Csa (Type I-A) module (lacking known invader sequence acquisition and crRNA processing genes) at another locus. The Pfu Cmr complex cleaves complementary target RNAs, and Csa systems have been shown to target DNA, while the mechanism by which Cst complexes silence invaders is unknown. In this study, we investigated the function of the Cst as well as Csa system in Pfu strains harboring a single CRISPR–Cas system. Plasmid transformation assays revealed that the Cst and Csa systems both function by DNA silencing and utilize similar flanking sequence information (PAMs) to identify invader DNA. Silencing by each system specifically requires its associated Cas3 nuclease. crRNAs from the 7 shared CRISPR loci in Pfu are processed for use by all 3 effector complexes, and Northern analysis revealed that individual effector complexes dictate the profile of mature crRNA species that is generated.
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Affiliation(s)
- Joshua Elmore
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Trace Deighan
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Jan Westpheling
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Rebecca M Terns
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Michael P Terns
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA Department of Genetics, University of Georgia, Athens, GA 30602, USA Department of Microbiology, University of Georgia, Athens, GA 30602, USA
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47
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Dwarakanath S, Brenzinger S, Gleditzsch D, Plagens A, Klingl A, Thormann K, Randau L. Interference activity of a minimal Type I CRISPR-Cas system from Shewanella putrefaciens. Nucleic Acids Res 2015; 43:8913-23. [PMID: 26350210 PMCID: PMC4605320 DOI: 10.1093/nar/gkv882] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 08/21/2015] [Accepted: 08/24/2015] [Indexed: 12/26/2022] Open
Abstract
Type I CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-Cas (CRISPR-associated) systems exist in bacterial and archaeal organisms and provide immunity against foreign DNA. The Cas protein content of the DNA interference complexes (termed Cascade) varies between different CRISPR-Cas subtypes. A minimal variant of the Type I-F system was identified in proteobacterial species including Shewanella putrefaciens CN-32. This variant lacks a large subunit (Csy1), Csy2 and Csy3 and contains two unclassified cas genes. The genome of S. putrefaciens CN-32 contains only five Cas proteins (Cas1, Cas3, Cas6f, Cas1821 and Cas1822) and a single CRISPR array with 81 spacers. RNA-Seq analyses revealed the transcription of this array and the maturation of crRNAs (CRISPR RNAs). Interference assays based on plasmid conjugation demonstrated that this CRISPR-Cas system is active in vivo and that activity is dependent on the recognition of the dinucleotide GG PAM (Protospacer Adjacent Motif) sequence and crRNA abundance. The deletion of cas1821 and cas1822 reduced the cellular crRNA pool. Recombinant Cas1821 was shown to form helical filaments bound to RNA molecules, which suggests its role as the Cascade backbone protein. A Cascade complex was isolated which contained multiple Cas1821 copies, Cas1822, Cas6f and mature crRNAs.
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Affiliation(s)
- Srivatsa Dwarakanath
- Prokaryotic Small RNA Biology, Max Planck Institute for Terrestrial Microbiology, Marburg, Hessen D-35043, Germany
| | - Susanne Brenzinger
- Institute for Microbiology and Molecular Biology, Justus-Liebig-University Giessen, Giessen, Hessen D-35392, Germany
| | - Daniel Gleditzsch
- Prokaryotic Small RNA Biology, Max Planck Institute for Terrestrial Microbiology, Marburg, Hessen D-35043, Germany
| | - André Plagens
- Prokaryotic Small RNA Biology, Max Planck Institute for Terrestrial Microbiology, Marburg, Hessen D-35043, Germany
| | - Andreas Klingl
- Plant Development, Department Biology I, Biocentre LMU Munich, Großhaderner Str. 2-4, Planegg-Martinsried D-82152, Germany
| | - Kai Thormann
- Institute for Microbiology and Molecular Biology, Justus-Liebig-University Giessen, Giessen, Hessen D-35392, Germany
| | - Lennart Randau
- Prokaryotic Small RNA Biology, Max Planck Institute for Terrestrial Microbiology, Marburg, Hessen D-35043, Germany LOEWE Center for Synthetic Microbiology (Synmikro), Marburg, Hessen D-35043, Germany
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48
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Wakefield N, Rajan R, Sontheimer EJ. Primary processing of CRISPR RNA by the endonuclease Cas6 in Staphylococcus epidermidis. FEBS Lett 2015; 589:3197-204. [PMID: 26364721 DOI: 10.1016/j.febslet.2015.09.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 09/04/2015] [Accepted: 09/07/2015] [Indexed: 12/11/2022]
Abstract
In many bacteria and archaea, an adaptive immune system (CRISPR-Cas) provides immunity against foreign genetic elements. This system uses CRISPR RNAs (crRNAs) derived from the CRISPR array, along with CRISPR-associated (Cas) proteins, to target foreign nucleic acids. In most CRISPR systems, endonucleolytic processing of crRNA precursors (pre-crRNAs) is essential for the pathway. Here we study the Cas6 endonuclease responsible for crRNA processing in the Type III-A CRISPR-Cas system from Staphylococcus epidermidis RP62a, a model for Type III-A CRISPR-Cas systems, and define substrate requirements for SeCas6 activity. We find that SeCas6 is necessary and sufficient for full-length crRNA biogenesis in vitro, and that it relies on both sequence and stem-loop structure in the 3' half of the CRISPR repeat for recognition and processing.
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Affiliation(s)
- Noelle Wakefield
- Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, IL 60208-3500, USA
| | - Rakhi Rajan
- Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, IL 60208-3500, USA
| | - Erik J Sontheimer
- Department of Molecular Biosciences, Northwestern University, 2205 Tech Drive, Evanston, IL 60208-3500, USA.
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49
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Hrle A, Maier LK, Sharma K, Ebert J, Basquin C, Urlaub H, Marchfelder A, Conti E. Structural analyses of the CRISPR protein Csc2 reveal the RNA-binding interface of the type I-D Cas7 family. RNA Biol 2015; 11:1072-82. [PMID: 25483036 PMCID: PMC4615900 DOI: 10.4161/rna.29893] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Upon pathogen invasion, bacteria and archaea activate an RNA-interference-like mechanism termed CRISPR (clustered regularly interspaced short palindromic repeats). A large family of Cas (CRISPR-associated) proteins mediates the different stages of this sophisticated immune response. Bioinformatic studies have classified the Cas proteins into families, according to their sequences and respective functions. These range from the insertion of the foreign genetic elements into the host genome to the activation of the interference machinery as well as target degradation upon attack. Cas7 family proteins are central to the type I and type III interference machineries as they constitute the backbone of the large interference complexes. Here we report the crystal structure of Thermofilum pendens Csc2, a Cas7 family protein of type I-D. We found that Csc2 forms a core RRM-like domain, flanked by three peripheral insertion domains: a lid domain, a Zinc-binding domain and a helical domain. Comparison with other Cas7 family proteins reveals a set of similar structural features both in the core and in the peripheral domains, despite the absence of significant sequence similarity. T. pendens Csc2 binds single-stranded RNA in vitro in a sequence-independent manner. Using a crosslinking - mass-spectrometry approach, we mapped the RNA-binding surface to a positively charged surface patch on T. pendens Csc2. Thus our analysis of the key structural and functional features of T. pendens Csc2 highlights recurring themes and evolutionary relationships in type I and type III Cas proteins.
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Key Words
- CRISPR
- CRISPR, Clustered regulatory short interspaced palindromic repeats
- Cas, CRISPR-associated
- Cas7
- H1 and H2 and H1-2, β-hairpins of insertion domain 1 (or lid domain)
- Mk, Methanopyrus kandleri
- RAMP, Repeat associated mysterious protein
- RNA binding
- RNAi, RNA interference
- RRM domain
- RRM, RNA recognition motif
- Rmsd, Root mean square deviation
- SAD, Single-wavelength anomalous dispersion
- Ss, Sulfolobus solfataricus
- Tp, Thermofilum pendens
- crRNA, CRISPR RNA
- dCASCADE, interference complex subtype I-D
- eCASCADE, interference complex subtype I-E
- prokaryotic immune system
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Affiliation(s)
- Ajla Hrle
- a Structural Cell Biology Department; Max Planck Institute of Biochemistry ; Martinsried , Germany
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50
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Majumdar S, Zhao P, Pfister NT, Compton M, Olson S, Glover CVC, Wells L, Graveley BR, Terns RM, Terns MP. Three CRISPR-Cas immune effector complexes coexist in Pyrococcus furiosus. RNA (NEW YORK, N.Y.) 2015; 21:1147-58. [PMID: 25904135 PMCID: PMC4436667 DOI: 10.1261/rna.049130.114] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 02/25/2015] [Indexed: 05/27/2023]
Abstract
CRISPR-Cas immune systems function to defend prokaryotes against potentially harmful mobile genetic elements including viruses and plasmids. The multiple CRISPR-Cas systems (Types I, II, and III) each target destruction of foreign nucleic acids via structurally and functionally diverse effector complexes (crRNPs). CRISPR-Cas effector complexes are comprised of CRISPR RNAs (crRNAs) that contain sequences homologous to the invading nucleic acids and Cas proteins specific to each immune system type. We have previously characterized a crRNP in Pyrococcus furiosus (Pfu) that contains Cmr (Type III-B) Cas proteins associated with one of two size classes of crRNAs and cleaves complementary target RNAs. Here, we have isolated and characterized two additional native Pfu crRNPs containing either Csa (Type I-A) or Cst (Type I-G) Cas proteins and distinct profiles of associated crRNAs. For each complex, the Cas proteins were identified by mass spectrometry and immunoblotting and the crRNAs by RNA sequencing and Northern blot analysis. The crRNAs associated with both the Csa and Cst complexes originate from all seven Pfu CRISPR loci and contain identical 5' ends (8-nt repeat-derived 5' tag sequences) but heterogeneous 3' ends (containing variable amounts of downstream repeat sequences). These crRNA forms are distinct from Cmr-associated crRNAs, indicating different 3' end processing pathways following primary cleavage of common pre-crRNAs. Like other previously characterized Type I CRISPR-Cas effector complexes, we predict that the newly identified Pfu Csa and Cst crRNPs each function to target invading DNA, adding an additional layer of protection beyond that afforded by the previously characterized RNA targeting Cmr complex.
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Affiliation(s)
- Sonali Majumdar
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Peng Zhao
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Neil T Pfister
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Mark Compton
- Department of Poultry Science, University of Georgia, Athens, Georgia 30602, USA
| | - Sara Olson
- Department of Genetics and Genome Sciences, Institute for Systems Genomics, University of Connecticut Health Center, Farmington, Connecticut 06030-6403, USA
| | - Claiborne V C Glover
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Lance Wells
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Brenton R Graveley
- Department of Genetics and Genome Sciences, Institute for Systems Genomics, University of Connecticut Health Center, Farmington, Connecticut 06030-6403, USA
| | - Rebecca M Terns
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA
| | - Michael P Terns
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, USA Department of Genetics, University of Georgia, Athens, Georgia 30602, USA Department of Microbiology, University of Georgia, Athens, Georgia 30602, USA
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