1
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Pawnikar S, Magenheimer BS, Joshi K, Nevarez-Munoz E, Haldane A, Maser RL, Miao Y. Activation of polycystin-1 signaling by binding of stalk-derived peptide agonists. eLife 2024; 13:RP95992. [PMID: 39373641 PMCID: PMC11458180 DOI: 10.7554/elife.95992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/08/2024] Open
Abstract
Polycystin-1 (PC1) is the protein product of the PKD1 gene whose mutation causes autosomal dominant Polycystic Kidney Disease (ADPKD). PC1 is an atypical G protein-coupled receptor (GPCR) with an autocatalytic GAIN domain that cleaves PC1 into extracellular N-terminal and membrane-embedded C-terminal (CTF) fragments. Recently, activation of PC1 CTF signaling was shown to be regulated by a stalk tethered agonist (TA), resembling the mechanism observed for adhesion GPCRs. Here, synthetic peptides of the first 9- (p9), 17- (p17), and 21-residues (p21) of the PC1 stalk TA were shown to re-activate signaling by a stalkless CTF mutant in human cell culture assays. Novel Peptide Gaussian accelerated molecular dynamics (Pep-GaMD) simulations elucidated binding conformations of p9, p17, and p21 and revealed multiple specific binding regions to the stalkless CTF. Peptide agonists binding to the TOP domain of PC1 induced close TOP-putative pore loop interactions, a characteristic feature of stalk TA-mediated PC1 CTF activation. Additional sequence coevolution analyses showed the peptide binding regions were consistent with covarying residue pairs identified between the TOP domain and the stalk TA. These insights into the structural dynamic mechanism of PC1 activation by TA peptide agonists provide an in-depth understanding that will facilitate the development of therapeutics targeting PC1 for ADPKD treatment.
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Affiliation(s)
- Shristi Pawnikar
- Center for Computational Biology and Department of Molecular Biosciences, University of KansasLawrenceUnited States
| | - Brenda S Magenheimer
- Clinical Laboratory Sciences, University of Kansas Medical CenterKansas CityUnited States
- The Jared Grantham Kidney Institute, University of Kansas Medical CenterKansas CityUnited States
| | - Keya Joshi
- Department of Pharmacology and Computational Medicine Program, University of North CarolinaChapel HillUnited States
| | - Ericka Nevarez-Munoz
- Clinical Laboratory Sciences, University of Kansas Medical CenterKansas CityUnited States
| | - Allan Haldane
- Department of Physics, and Center for Biophysics and Computational Biology, Temple UniversityPhiladelphiaUnited States
| | - Robin L Maser
- Clinical Laboratory Sciences, University of Kansas Medical CenterKansas CityUnited States
- The Jared Grantham Kidney Institute, University of Kansas Medical CenterKansas CityUnited States
- Department of Biochemistry and Molecular Biology, University of Kansas Medical CenterKansas CityUnited States
| | - Yinglong Miao
- Department of Pharmacology and Computational Medicine Program, University of North CarolinaChapel HillUnited States
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2
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Jeong SH, Lee HJ, Lee SJ. Use of paired Cas9-NG nickase and truncated sgRNAs for single-nucleotide microbial genome editing. Front Genome Ed 2024; 6:1471720. [PMID: 39391173 PMCID: PMC11464485 DOI: 10.3389/fgeed.2024.1471720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2024] [Accepted: 09/19/2024] [Indexed: 10/12/2024] Open
Abstract
The paired nickases approach, which utilizes clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated proteins (Cas) nickase and dual guide RNA, has the advantage of reducing off-target effects by being able to double the target sequence. In this study, our research utilized the Cas9-NG nickase variant to minimize PAM sequence constraints, enabling the generation of paired nicks at desired genomic loci. We performed a systematic investigation into the formation sites for double nicks and the design of donor DNA within a bacterial model system. Although we successfully identified the conditions necessary for the effective formation of double nicks in vivo, achieving single-nucleotide level editing directly at the target sites in the genome proved challenging. Nonetheless, our experiments revealed that efficient editing at the single-nucleotide level was achievable on target DNA sequences that are hybridized with 5'-end-truncated dual single-guide RNAs (sgRNAs). Our findings contribute to a deeper understanding of the paired nickases approach, offering a single-mismatch intolerance design strategy for accurate nucleotide editing. This strategy not only enhances the precision of genome editing but also marks a significant step forward in the development of nickase-derived genome editing technologies.
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Affiliation(s)
| | | | - Sang Jun Lee
- Department of Systems Biotechnology, Institute of Microbiomics, Chung-Ang University, Anseong, Republic of Korea
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3
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Daskalakis V, Papapetros S. Engineering salt-tolerant Cas12f1 variants for gene-editing applications. J Biomol Struct Dyn 2024; 42:7421-7431. [PMID: 37526217 DOI: 10.1080/07391102.2023.2240418] [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: 04/04/2023] [Accepted: 07/17/2023] [Indexed: 08/02/2023]
Abstract
CRISPR has revolutionized the field of genome editing in life sciences by serving as a versatile and state-of-the-art tool. Cas12f1 is a small nuclease of the bacterial immunity CRISPR system with an ideal size for cellular delivery, in contrast to CRISPR-associated (Cas) proteins like Cas9 or Cas12. However, Cas12f1 works best at low salt concentrations. In this study, we find that the plasticity of certain Cas12f1 regions (K196-Y202 and I452-L515) is negatively affected by increased salt concentrations. On this line, key protein domains (REC1, WED, Nuc, lid) that are involved in the DNA-target recognition and the activation of the catalytic RuvC domain are in turn also affected. We suggest that salt concentration should be taken in to consideration for activity assessments of Cas engineered variants, especially if the mutations are on the protospacer adjacent motif interacting domain. The results can be exploited for the engineering of Cas variants and the assessment of their activity at varying salt concentrations. We propose that the K198Q mutation can restore at great degree the compromised plasticity and could potentially lead to salt-tolerant Cas12f1 variants. The methodology can be also employed for the study of biomolecules in terms of their salinity tolerance.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Vangelis Daskalakis
- Department of Chemical Engineering, Cyprus University of Technology, Limassol, Cyprus
| | - Spyridon Papapetros
- Department of Chemical Engineering, Cyprus University of Technology, Limassol, Cyprus
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4
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Liu Y, Wang K, Cao F, Gao N, Li W. Interactions between Inhibitors and 5-Lipoxygenase: Insights from Gaussian Accelerated Molecular Dynamics and Markov State Models. Int J Mol Sci 2024; 25:8295. [PMID: 39125865 PMCID: PMC11311652 DOI: 10.3390/ijms25158295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2024] [Revised: 07/27/2024] [Accepted: 07/28/2024] [Indexed: 08/12/2024] Open
Abstract
Inflammation is a protective stress response triggered by external stimuli, with 5-lipoxygenase (5LOX) playing a pivotal role as a potent mediator of the leukotriene (Lts) inflammatory pathway. Nordihydroguaiaretic acid (NDGA) functions as a natural orthosteric inhibitor of 5LOX, while 3-acetyl-11-keto-β-boswellic acid (AKBA) acts as a natural allosteric inhibitor targeting 5LOX. However, the precise mechanisms of inhibition have remained unclear. In this study, Gaussian accelerated molecular dynamics (GaMD) simulation was employed to elucidate the inhibitory mechanisms of NDGA and AKBA on 5LOX. It was found that the orthosteric inhibitor NDGA was tightly bound in the protein's active pocket, occupying the active site and inhibiting the catalytic activity of the 5LOX enzyme through competitive inhibition. The binding of the allosteric inhibitor AKBA induced significant changes at the distal active site, leading to a conformational shift of residues 168-173 from a loop to an α-helix and significant negative correlated motions between residues 285-290 and 375-400, reducing the distance between these segments. In the simulation, the volume of the active cavity in the stable conformation of the protein was reduced, hindering the substrate's entry into the active cavity and, thereby, inhibiting protein activity through allosteric effects. Ultimately, Markov state models (MSM) were used to identify and classify the metastable states of proteins, revealing the transition times between different conformational states. In summary, this study provides theoretical insights into the inhibition mechanisms of 5LOX by AKBA and NDGA, offering new perspectives for the development of novel inhibitors specifically targeting 5LOX, with potential implications for anti-inflammatory drug development.
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Affiliation(s)
- Yuyang Liu
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, China; (Y.L.); (K.W.)
| | - Kaiyu Wang
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, China; (Y.L.); (K.W.)
| | - Fuyan Cao
- Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, School of Life Sciences, Jilin University, Changchun 130012, China;
| | - Nan Gao
- Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun 130024, China
| | - Wannan Li
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, China; (Y.L.); (K.W.)
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5
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Pawnikar S, Magenheimer BS, Joshi K, Munoz EN, Haldane A, Maser RL, Miao Y. Activation of Polycystin-1 Signaling by Binding of Stalk-derived Peptide Agonists. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.06.574465. [PMID: 38260358 PMCID: PMC10802338 DOI: 10.1101/2024.01.06.574465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Polycystin-1 (PC1) is the membrane protein product of the PKD1 gene whose mutation is responsible for 85% of the cases of autosomal dominant polycystic kidney disease (ADPKD). ADPKD is primarily characterized by the formation of renal cysts and potential kidney failure. PC1 is an atypical G protein-coupled receptor (GPCR) consisting of 11 transmembrane helices and an autocatalytic GAIN domain that cleaves PC1 into extracellular N-terminal (NTF) and membrane-embedded C-terminal (CTF) fragments. Recently, signaling activation of the PC1 CTF was shown to be regulated by a stalk tethered agonist (TA), a distinct mechanism observed in the adhesion GPCR family. A novel allosteric activation pathway was elucidated for the PC1 CTF through a combination of Gaussian accelerated molecular dynamics (GaMD), mutagenesis and cellular signaling experiments. Here, we show that synthetic, soluble peptides with 7 to 21 residues derived from the stalk TA, in particular, peptides including the first 9 residues (p9), 17 residues (p17) and 21 residues (p21) exhibited the ability to re-activate signaling by a stalkless PC1 CTF mutant in cellular assays. To reveal molecular mechanisms of stalk peptide-mediated signaling activation, we have applied a novel Peptide GaMD (Pep-GaMD) algorithm to elucidate binding conformations of selected stalk peptide agonists p9, p17 and p21 to the stalkless PC1 CTF. The simulations revealed multiple specific binding regions of the stalk peptide agonists to the PC1 protein including an "intermediate" bound yet inactive state. Our Pep-GaMD simulation findings were consistent with the cellular assay experimental data. Binding of peptide agonists to the TOP domain of PC1 induced close TOP-putative pore loop interactions, a characteristic feature of the PC1 CTF signaling activation mechanism. Using sequence covariation analysis of PC1 homologs, we further showed that the peptide binding regions were consistent with covarying residue pairs identified between the TOP domain and the stalk TA. Therefore, structural dynamic insights into the mechanisms of PC1 activation by stalk-derived peptide agonists have enabled an in-depth understanding of PC1 signaling. They will form a foundation for development of PC1 as a therapeutic target for the treatment of ADPKD.
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Affiliation(s)
- Shristi Pawnikar
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66047
| | - Brenda S. Magenheimer
- Clinical Laboratory Sciences, University of Kansas Medical Center, Kansas City, KS 66160
- The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS 66160
| | - Keya Joshi
- Department of Pharmacology and Computational Medicine Program, University of North Carolina – Chapel Hill, Chapel Hill, NC 27599
| | - Ericka Nevarez Munoz
- Clinical Laboratory Sciences, University of Kansas Medical Center, Kansas City, KS 66160
| | - Allan Haldane
- Dept of Physics, and Center for Biophysics and Computational Biology, Temple University, Philadelphia, PA 19122
| | - Robin L. Maser
- Departments of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS 66160
- Clinical Laboratory Sciences, University of Kansas Medical Center, Kansas City, KS 66160
- The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, KS 66160
| | - Yinglong Miao
- Department of Pharmacology and Computational Medicine Program, University of North Carolina – Chapel Hill, Chapel Hill, NC 27599
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6
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Dey D, Chakravarti R, Bhattacharjee O, Majumder S, Chaudhuri D, Ahmed KT, Roy D, Bhattacharya B, Arya M, Gautam A, Singh R, Gupta R, Ravichandiran V, Chattopadhyay D, Ghosh A, Giri K, Roy S, Ghosh D. A mechanistic study on the tolerance of PAM distal end mismatch by SpCas9. J Biol Chem 2024; 300:107439. [PMID: 38838774 PMCID: PMC11267045 DOI: 10.1016/j.jbc.2024.107439] [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: 11/19/2023] [Revised: 05/23/2024] [Accepted: 05/24/2024] [Indexed: 06/07/2024] Open
Abstract
The therapeutic application of CRISPR-Cas9 is limited due to its off-target activity. To have a better understanding of this off-target effect, we focused on its mismatch-prone PAM distal end. The off-target activity of SpCas9 depends directly on the nature of mismatches, which in turn results in deviation of the active site of SpCas9 due to structural instability in the RNA-DNA duplex strand. In order to test the hypothesis, we designed an array of mismatched target sites at the PAM distal end and performed in vitro and cell line-based experiments, which showed a strong correlation for Cas9 activity. We found that target sites having multiple mismatches in the 18th to 15th position upstream of the PAM showed no to little activity. For further mechanistic validation, Molecular Dynamics simulations were performed, which revealed that certain mismatches showed elevated root mean square deviation values that can be attributed to conformational instability within the RNA-DNA duplex. Therefore, for successful prediction of the off-target effect of SpCas9, along with complementation-derived energy, the RNA-DNA duplex stability should be taken into account.
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Affiliation(s)
- Dhritiman Dey
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India
| | - Rudra Chakravarti
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India
| | - Oindrila Bhattacharjee
- Plant-Microbe Interaction Division, National Institute of Plant Genome Research, Delhi, India
| | | | | | - Kazi Tawsif Ahmed
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India
| | - Dipanjan Roy
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India
| | - Bireswar Bhattacharya
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India
| | - Mansi Arya
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India
| | - Anupam Gautam
- Algorithms in Bioinformatics, Institute for Bioinformatics and Medical Informatics, University of Tübingen, Tübingen, Baden-Württemberg, Germany; International Max Planck Research School 'From Molecules to Organisms', Max Planck Institute for Biology, Tübingen, Baden-Württemberg, Germany
| | - Rajveer Singh
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India
| | - Rahul Gupta
- Infectious Diseases and Immunology Division, Indian Institute of Chemical Biology, Kolkata, West Bengal, India
| | - Velayutham Ravichandiran
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India
| | | | - Abhrajyoti Ghosh
- Department of Biochemistry, Bose Institute, Kolkata, West Bengal, India
| | - Kalyan Giri
- Department of Life Sciences, Presidency University, Kolkata, India
| | - Syamal Roy
- Infectious Diseases and Immunology Division, Indian Institute of Chemical Biology, Kolkata, West Bengal, India
| | - Dipanjan Ghosh
- Department of Natural Products, National Institute of Pharmaceutical Education and Research, Kolkata, West Bengal, India.
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7
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Patel A, Sinha S, Arantes P, Palermo G. Unveiling Cas8 Dynamics and Regulation within a transposon-encoded Cascade-TniQ Complex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.21.600075. [PMID: 38948825 PMCID: PMC11213026 DOI: 10.1101/2024.06.21.600075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Cascade is a class 1, type 1 CRISPR-Cas system with a variety of roles in prokaryote defense, specifically against DNA-based viruses. The Vibrio Cholerae transposon, Tn6677, encodes a variant of the type 1F Cascade known as type 1F-3. This Cascade variant complexes with a homodimer of the transposition protein TniQ and leverages the sequence specificity of Cascade to direct the integration activity of the heteromeric transposase tnsA/B, resulting in site-specific transposition of Tn6677. We desire to uncover the molecular details behind R Loop formation of 'Cascade-TniQ.' Due to the lack of a complete model of Cascade-TniQ available at atom-level resolution, we first build a complete model using AlphaFold V2.1. We then simulate this model via classical molecular dynamics and umbrella sampling to study an important regulatory component within Cascade-TniQ, known as the Cas8 'bundle.' Particularly, we show that this alpha helical bundle experiences a free energy barrier to its large-scale translatory motions and relative free energies of its states primarily dependent on a loop within a Cas7 subunit in Cascade-TniQ. Further, we comment on additional structural and dynamical regulatory points of Cascade-TniQ during R Loop formation, such as Cascade-TniQ backbone rigidity, and the potential role TniQ plays in regulating bundle dynamics. In summary, our outcomes provide the first all-atom dynamic representation of one of the largest CRISPR systems, with information that can contribute to understanding the mechanism of nucleic acid binding and, eventually, to transposase recruitment itself. Such information may prove informative to advance genome engineering efforts.
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8
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Zhao L, Wang J, Yang W, Zhao K, Sun Q, Chen J. Unveiling Conformational States of CDK6 Caused by Binding of Vcyclin Protein and Inhibitor by Combining Gaussian Accelerated Molecular Dynamics and Deep Learning. Molecules 2024; 29:2681. [PMID: 38893554 PMCID: PMC11174096 DOI: 10.3390/molecules29112681] [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: 05/08/2024] [Revised: 05/29/2024] [Accepted: 06/03/2024] [Indexed: 06/21/2024] Open
Abstract
CDK6 plays a key role in the regulation of the cell cycle and is considered a crucial target for cancer therapy. In this work, conformational transitions of CDK6 were identified by using Gaussian accelerated molecular dynamics (GaMD), deep learning (DL), and free energy landscapes (FELs). DL finds that the binding pocket as well as the T-loop binding to the Vcyclin protein are involved in obvious differences of conformation contacts. This result suggests that the binding pocket of inhibitors (LQQ and AP9) and the binding interface of CDK6 to the Vcyclin protein play a key role in the function of CDK6. The analyses of FELs reveal that the binding pocket and the T-loop of CDK6 have disordered states. The results from principal component analysis (PCA) indicate that the binding of the Vcyclin protein affects the fluctuation behavior of the T-loop in CDK6. Our QM/MM-GBSA calculations suggest that the binding ability of LQQ to CDK6 is stronger than AP9 with or without the binding of the Vcyclin protein. Interaction networks of inhibitors with CDK6 were analyzed and the results reveal that LQQ contributes more hydrogen binding interactions (HBIs) and hot interaction spots with CDK6. In addition, the binding pocket endures flexibility changes from opening to closing states and the Vcyclin protein plays an important role in the stabilizing conformation of the T-loop. We anticipate that this work could provide useful information for further understanding the function of CDK6 and developing new promising inhibitors targeting CDK6.
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Affiliation(s)
- Lu Zhao
- School of Science, Shandong Jiaotong University, Jinan 250357, China; (J.W.); (W.Y.); (K.Z.); (Q.S.)
| | | | | | | | | | - Jianzhong Chen
- School of Science, Shandong Jiaotong University, Jinan 250357, China; (J.W.); (W.Y.); (K.Z.); (Q.S.)
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9
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Zhao S, Liu J, Zuo Z. Secondary Conformational Checkpoint in CRISPR-Cas9. J Chem Theory Comput 2024; 20:3440-3448. [PMID: 38625092 DOI: 10.1021/acs.jctc.4c00120] [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] [Indexed: 04/17/2024]
Abstract
A specific checkpoint between target DNA binding and cleavage primarily governs the precision of Cas9 gene editing. Although various CRISPR-Cas9 variants have been developed to improve DNA cleavage accuracy, we still lack a comprehensive understanding of how they work at the molecular level. Herein, we have focused on studying the late-stage conformational transitions of Cas9 and an evolved Cas9 mutant (evoCas9) that start from the precleavage state. Our submilliseconds of dynamic simulations reveal that the presence of base mismatches leads the HNH nuclease domain of Cas9 to alter its principal functional modes of motion, thereby impairing its conformational activation. This observation suggests the existence of a secondary conformational checkpoint that fine-tunes the final DNA cleavage activation. Remarkably, evoCas9 is prone to deviating from the normal activation pathway with base mismatches. This is characterized by a noticeable shift in the positioning of the HNH domain and a significantly perturbed allosteric communication network within the enzyme. Therefore, the mutations evolved in evoCas9 also reinforce the secondary checkpoint in addition to the previously identified primary checkpoint, collectively ensuring this variant's high gene-editing accuracy. This mechanism should also apply to other Cas9-guide RNA variants with enhanced fidelity.
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Affiliation(s)
- Shuxin Zhao
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China
- Shanghai Frontiers Science Research Center for Druggability of Cardiovascular noncoding RNA, Institute for Frontier Medical Technology, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Jin Liu
- Department of Pharmaceutical Sciences, University of North Texas System College of Pharmacy, University of North Texas Health Science Center, Fort Worth, Texas 76107, United States
| | - Zhicheng Zuo
- College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China
- Shanghai Frontiers Science Research Center for Druggability of Cardiovascular noncoding RNA, Institute for Frontier Medical Technology, Shanghai University of Engineering Science, Shanghai 201620, China
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10
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Bhattacharya S, Satpati P. Why Does the E1219V Mutation Expand T-Rich PAM Recognition in Cas9 from Streptococcus pyogenes? J Chem Inf Model 2024; 64:3237-3247. [PMID: 38600752 DOI: 10.1021/acs.jcim.3c01515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
Popular RNA-guided DNA endonuclease Cas9 from Streptococcus pyogenes (SpCas9) recognizes the canonical 5'-NGG-3' protospacer adjacent motif (PAM) and triggers double-stranded DNA cleavage activity. Mutations in SpCas9 were demonstrated to expand the PAM readability and hold promise for therapeutic and genome editing applications. However, the energetics of the PAM recognition and its relation to the atomic structure remain unknown. Using the X-ray structure (precatalytic SpCas9:sgRNA:dsDNA) as a template, we calculated the change in the PAM binding affinity in response to SpCas9 mutations using computer simulations. The E1219V mutation in SpCas9 fine-tunes the water accessibility in the PAM binding pocket and promotes new interactions in the SpCas9:noncanonical T-rich PAM, thus weakening the PAM stringency. The nucleotide-specific interaction of two arginine residues (i.e., R1333 and R1335 of SpCas9) ensured stringent 5'-NGG-3' PAM recognition. R1335A substitution (SpCas9R1335A) completely disrupts the direct interaction between SpCas9 and PAM sequences (canonical or noncanonical), accounting for the loss of editing activity. Interestingly, the double mutant (SpCas9R1335A,E1219V) boosts DNA binding affinity by favoring protein:PAM electrostatic contact in a desolvated pocket. The underlying thermodynamics explain the varied DNA cleavage activity of SpCas9 variants. A direct link between the energetics, structures, and activity is highlighted, which can aid in the rational design of improved SpCas9-based genome editing tools.
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Affiliation(s)
- Shreya Bhattacharya
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Priyadarshi Satpati
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
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11
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Skeens E, Sinha S, Ahsan M, D’Ordine AM, Jogl G, Palermo G, Lisi GP. High-fidelity, hyper-accurate, and evolved mutants rewire atomic-level communication in CRISPR-Cas9. SCIENCE ADVANCES 2024; 10:eadl1045. [PMID: 38446895 PMCID: PMC10917355 DOI: 10.1126/sciadv.adl1045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 01/29/2024] [Indexed: 03/08/2024]
Abstract
The high-fidelity (HF1), hyper-accurate (Hypa), and evolved (Evo) variants of the CRISPR-associated protein 9 (Cas9) endonuclease are critical tools to mitigate off-target effects in the application of CRISPR-Cas9 technology. The mechanisms by which mutations in recognition subdomain 3 (Rec3) mediate specificity in these variants are poorly understood. Here, solution nuclear magnetic resonance and molecular dynamics simulations establish the structural and dynamic effects of high-specificity mutations in Rec3, and how they propagate the allosteric signal of Cas9. We reveal conserved structural changes and dynamic differences at regions of Rec3 that interface with the RNA:DNA hybrid, transducing chemical signals from Rec3 to the catalytic His-Asn-His (HNH) domain. The variants remodel the communication sourcing from the Rec3 α helix 37, previously shown to sense target DNA complementarity, either directly or allosterically. This mechanism increases communication between the DNA mismatch recognition helix and the HNH active site, shedding light on the structure and dynamics underlying Cas9 specificity and providing insight for future engineering principles.
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Affiliation(s)
- Erin Skeens
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA
| | - Souvik Sinha
- Department of Bioengineering, University of California, Riverside, Riverside, CA, USA
| | - Mohd Ahsan
- Department of Bioengineering, University of California, Riverside, Riverside, CA, USA
| | - Alexandra M. D’Ordine
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA
| | - Gerwald Jogl
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA
| | - Giulia Palermo
- Department of Bioengineering, University of California, Riverside, Riverside, CA, USA
- Department of Chemistry, University of California, Riverside, Riverside, CA, USA
| | - George P. Lisi
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA
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12
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Sk MF, Samanta S, Poddar S, Kar P. Deciphering the molecular choreography of Janus kinase 2 inhibition via Gaussian accelerated molecular dynamics simulations: a dynamic odyssey. J Comput Aided Mol Des 2024; 38:8. [PMID: 38324213 DOI: 10.1007/s10822-023-00548-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 12/24/2023] [Indexed: 02/08/2024]
Abstract
The Janus kinases (JAK) are crucial targets in drug development for several diseases. However, accounting for the impact of possible structural rearrangements on the binding of different kinase inhibitors is complicated by the extensive conformational variability of their catalytic kinase domain (KD). The dynamic KD contains mainly four prominent mobile structural motifs: the phosphate-binding loop (P-loop), the αC-helix within the N-lobe, the Asp-Phe-Gly (DFG) motif, and the activation loop (A-loop) within the C-lobe. These distinct structural orientations imply a complex signal transmission path for regulating the A-loop's flexibility and conformational preference for optimal JAK function. Nevertheless, the precise dynamical features of the JAK induced by different types of inhibitors still remain elusive. We performed comparative, microsecond-long, Gaussian accelerated molecular dynamics simulations in triplicate of three phosphorylated JAK2 systems: the KD alone, type-I ATP-competitive inhibitor (CI) bound KD in the catalytically active DFG-in conformation, and the type-II inhibitor (AI) bound KD in the catalytically inactive DFG-out conformation. Our results indicate significant conformational variations observed in the A-loop and αC helix motions upon inhibitor binding. Our studies also reveal that the DFG-out inactive conformation is characterized by the closed A-loop rearrangement, open catalytic cleft of N and C-lobe, the outward movement of the αC helix, and open P-loop states. Moreover, the outward positioning of the αC helix impacts the hallmark salt bridge formation between Lys882 and Glu898 in an inactive conformation. Finally, we compared their ligand binding poses and free energy by the MM/PBSA approach. The free energy calculations suggested that the AI's binding affinity is higher than CI against JAK2 due to an increased favorable contribution from the total non-polar interactions and the involvement of the αC helix. Overall, our study provides the structural and energetic insights crucial for developing more promising type I/II JAK2 inhibitors for treating JAK-related diseases.
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Affiliation(s)
- Md Fulbabu Sk
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Khandwa Road, Simrol, MP, 453552, India
- Theoretical and Computational Biophysics Group, Beckman Institute for Advanced Science and Technology, NIH Resource for Macromolecular Modeling and Visualization, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Sunanda Samanta
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Khandwa Road, Simrol, MP, 453552, India
| | - Sayan Poddar
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Khandwa Road, Simrol, MP, 453552, India
| | - Parimal Kar
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Khandwa Road, Simrol, MP, 453552, India.
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13
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Adediwura VA, Miao Y. Mechanistic Insights into Peptide Binding and Deactivation of an Adhesion G Protein-Coupled Receptor. Molecules 2023; 29:164. [PMID: 38202747 PMCID: PMC10780249 DOI: 10.3390/molecules29010164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/20/2023] [Accepted: 12/23/2023] [Indexed: 01/12/2024] Open
Abstract
Adhesion G protein-coupled receptors (ADGRGs) play critical roles in the reproductive, neurological, cardiovascular, and endocrine systems. In particular, ADGRG2 plays a significant role in Ewing sarcoma cell proliferation, parathyroid cell function, and male fertility. In 2022, a cryo-EM structure was reported for the active ADGRG2 bound by an optimized peptide agonist IP15 and the Gs protein. The IP15 peptide agonist was also modified to antagonists 4PH-E and 4PH-D with mutations of the 4PH residue to Glu and Asp, respectively. However, experimental structures of inactive antagonist-bound ADGRs remain to be resolved, and the activation mechanism of ADGRs such as ADGRG2 is poorly understood. Here, we applied Gaussian accelerated molecular dynamics (GaMD) simulations to probe conformational dynamics of the agonist- and antagonist-bound ADGRG2. By performing GaMD simulations, we were able to identify important low-energy conformations of ADGRG2 in the active, intermediate, and inactive states, as well as explore the binding conformations of each peptide. Moreover, our simulations revealed critical peptide-receptor residue interactions during the deactivation of ADGRG2. In conclusion, through GaMD simulations, we uncovered mechanistic insights into peptide (agonist and antagonist) binding and deactivation of the ADGRG2. These findings will potentially facilitate rational design of new peptide modulators of ADGRG2 and other ADGRs.
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Affiliation(s)
| | - Yinglong Miao
- Department of Pharmacology and Computational Medicine Program, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA;
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14
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Wang J, Maschietto F, Qiu T, Arantes PR, Skeens E, Palermo G, Lisi GP, Batista VS. Substrate-independent activation pathways of the CRISPR-Cas9 HNH nuclease. Biophys J 2023; 122:4635-4644. [PMID: 37936350 PMCID: PMC10754686 DOI: 10.1016/j.bpj.2023.11.005] [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: 07/13/2023] [Revised: 10/29/2023] [Accepted: 11/03/2023] [Indexed: 11/09/2023] Open
Abstract
A hallmark of tightly regulated high-fidelity enzymes is that they become activated only after encountering cognate substrates, often by an induced-fit mechanism rather than conformational selection. Upon analysis of molecular dynamics trajectories, we recently discovered that the Cas9 HNH domain exists in three conformations: 1) Y836 (which is two residues away from the catalytic D839 and H840 residues) is hydrogen bonded to the D829 backbone amide, 2) Y836 is hydrogen bonded to the backbone amide of D861 (which is one residue away from the third catalytic residue N863), and 3) Y836 is not hydrogen bonded to either residue. Each of the three conformers differs from the active state of HNH. The conversion between the inactive and active states involves a local unfolding-refolding process that displaces the Cα and side chain of the catalytic N863 residue by ∼5 Å and ∼10 Å, respectively. In this study, we report the two largest principal components of coordinate variance of the HNH domain throughout molecular dynamics trajectories to establish the interconversion pathways of these conformations. We show that conformation 2 is an obligate step between conformations 1 and 3, which are not directly interconvertible without conformation 2. The loss of hydrogen bonding of the Y836 side chain in conformation 3 likely plays an essential role in activation during local unfolding-refolding of an α-helix containing the catalytic N863. Three single Lys-to-Ala mutants appear to eliminate this substrate-independent activation pathway of the wild-type HNH nuclease, thereby enhancing the fidelity of HNH cleavage.
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Affiliation(s)
- Jimin Wang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut.
| | | | - Tianyin Qiu
- Department of Chemistry, Yale University, New Haven, Connecticut
| | - Pablo R Arantes
- Department of Bioengineering, University of California, Riverside, Riverside, California
| | - Erin Skeens
- Department of Chemistry, University of California, Riverside, Riverside, California
| | - Giulia Palermo
- Department of Bioengineering, University of California, Riverside, Riverside, California; Department of Chemistry, University of California, Riverside, Riverside, California.
| | - George P Lisi
- Department of Molecular and Cell Biology and Biochemistry, Brown University, Providence, Rhode Island.
| | - Victor S Batista
- Department of Chemistry, Yale University, New Haven, Connecticut.
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15
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Caparotta M, Perez A. When MELD Meets GaMD: Accelerating Biomolecular Landscape Exploration. J Chem Theory Comput 2023; 19:8743-8750. [PMID: 38039424 DOI: 10.1021/acs.jctc.3c01019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2023]
Abstract
We introduce Gaussian accelerated MELD (GaMELD) as a new method for exploring the energy landscape of biomolecules. GaMELD combines the strengths of Gaussian accelerated molecular dynamics (GaMD) and modeling employing limited data (MELD) to navigate complex energy landscapes. MELD uses replica-exchange molecular simulations to integrate limited and uncertain data into simulations via Bayesian inference. MELD has been successfully applied to problems of structure prediction like protein folding and complex structure prediction. However, the computational cost for MELD simulations has limited its broader applicability. The synergy of GaMD and MELD surmounts this limitation efficiently sampling the energy landscape at a lower computational cost (reducing the computational cost by a factor of 2 to six). Effectively, GaMD is used to shift energy distributions along replicas to increase the overlap in energy distributions across replicas, facilitating a random walk in replica space. We tested GaMELD on a benchmark set of 12 small proteins that have been previously studied through MELD and conventional MD. GaMELD consistently achieves accurate predictions with fewer replicas. By increasing the efficacy of replica exchange, GaMELD effectively accelerates convergence in the conformational space, enabling improved sampling across a diverse set of systems.
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Affiliation(s)
- Marcelo Caparotta
- Department of Chemistry and Quantum Theory Project, University of Florida, Gainesville, Florida 32611, United States
| | - Alberto Perez
- Department of Chemistry and Quantum Theory Project, University of Florida, Gainesville, Florida 32611, United States
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16
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Baroroh U, Chantika NS, Firdaus ARR, Tohari TR, Subroto T, Ishmayana S, Safari A, Rachman SD, Yusuf M. Accelerated molecular dynamics study to compare the thermostability of Bacillus licheniformis and Aspergillus niger α-amylase. J Biomol Struct Dyn 2023:1-11. [PMID: 37979153 DOI: 10.1080/07391102.2023.2283152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 11/06/2023] [Indexed: 11/20/2023]
Abstract
The thermostability of enzymes plays a significant role in the starch hydrolysis process in the industry. The structural difference between thermostable Bacillus licheniformis α-amylase (BLA) and thermolabile Aspergillus niger α-amylase (ANA) is interesting to be explored. This work aimed to study the thermostability-determining factor of BLA as compared to a non-thermostable enzyme, ANA, using molecular dynamics (MD) simulation at a high temperature. A 100 ns of classical MD, which was followed by 200 ns accelerated MD was conducted to explore the conformational changes of the enzyme. It is revealed that the intramolecular interactions through salt bridge interactions and the presence of calcium ions dominates the stability effect of BLA, despite the absence of a disulfide bond in the structure. These results should be useful in designing a thermostable enzyme that can be used in industrial processes.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Umi Baroroh
- Department of Biotechnology, Indonesia School of Pharmacy, Bandung, Indonesia
| | - Nindi Salma Chantika
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang, Indonesia
| | - Ade R R Firdaus
- Research Center for Molecular Biotechnology and Bioinformatics, Universitas Padjadjaran, Bandung, Indonesia
| | - Taufik Ramdani Tohari
- Research Center for Molecular Biotechnology and Bioinformatics, Universitas Padjadjaran, Bandung, Indonesia
| | - Toto Subroto
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang, Indonesia
- Research Center for Molecular Biotechnology and Bioinformatics, Universitas Padjadjaran, Bandung, Indonesia
| | - Safri Ishmayana
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang, Indonesia
| | - Agus Safari
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang, Indonesia
| | - Saadah Diana Rachman
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang, Indonesia
| | - Muhammad Yusuf
- Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran, Sumedang, Indonesia
- Research Center for Molecular Biotechnology and Bioinformatics, Universitas Padjadjaran, Bandung, Indonesia
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17
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Mustali J, Yasuda I, Hirano Y, Yasuoka K, Gautieri A, Arai N. Unsupervised deep learning for molecular dynamics simulations: a novel analysis of protein-ligand interactions in SARS-CoV-2 M pro. RSC Adv 2023; 13:34249-34261. [PMID: 38019981 PMCID: PMC10663885 DOI: 10.1039/d3ra06375e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 11/06/2023] [Indexed: 12/01/2023] Open
Abstract
Molecular dynamics (MD) simulations, which are central to drug discovery, offer detailed insights into protein-ligand interactions. However, analyzing large MD datasets remains a challenge. Current machine-learning solutions are predominantly supervised and have data labelling and standardisation issues. In this study, we adopted an unsupervised deep-learning framework, previously benchmarked for rigid proteins, to study the more flexible SARS-CoV-2 main protease (Mpro). We ran MD simulations of Mpro with various ligands and refined the data by focusing on binding-site residues and time frames in stable protein conformations. The optimal descriptor chosen was the distance between the residues and the center of the binding pocket. Using this approach, a local dynamic ensemble was generated and fed into our neural network to compute Wasserstein distances across system pairs, revealing ligand-induced conformational differences in Mpro. Dimensionality reduction yielded an embedding map that correlated ligand-induced dynamics and binding affinity. Notably, the high-affinity compounds showed pronounced effects on the protein's conformations. We also identified the key residues that contributed to these differences. Our findings emphasize the potential of combining unsupervised deep learning with MD simulations to extract valuable information and accelerate drug discovery.
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Affiliation(s)
- Jessica Mustali
- Department of Electronics, Information and Bioengineering, Politecnico di Milano Italy
| | - Ikki Yasuda
- Department of Mechanical Engineering, Keio University Japan
| | | | - Kenji Yasuoka
- Department of Mechanical Engineering, Keio University Japan
| | - Alfonso Gautieri
- Department of Electronics, Information and Bioengineering, Politecnico di Milano Italy
| | - Noriyoshi Arai
- Department of Mechanical Engineering, Keio University Japan
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18
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Zhao J, Hu H, Zhou H, Zhang J, Wang L, Wang R. Reactive oxygen signaling molecule inducible regulation of CRISPR-Cas9 gene editing. Cell Biol Toxicol 2023; 39:2421-2429. [PMID: 35644856 DOI: 10.1007/s10565-022-09723-3] [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: 12/09/2021] [Accepted: 05/11/2022] [Indexed: 11/02/2022]
Abstract
We report development of a controllable gene editing tool that boronated gRNA, simply generated in situ, could regulate binding of gRNA molecules with either Cas9 endonuclease or target genes, thus serving as a modulator that can control CRISPR-Cas9 gene editing. Subsequent treatment with H2O2 facilitates the restoration of gene editing ability of the boronated gRNA to the level of using untreated gRNA. This is one of the few cases using small molecule to regulate CRISPR-Cas9 gene editing, which is a complement to the light approach, displaying great application potential. We develop a controllable gene editing tools based on the CRISPR-Cas9 gene editing system. This tool can be regulated by oxidative small molecule, i.e., H2O2. Compared with the light method, the application scope of our CRISPR-Cas9 systems have been widened with the small-molecule-triggered approaches, preventing the potential damage of cells or organism caused by UV light. In addition, the gain-of-function tools are expanding the gene code expansion for mechanistic studies of target enzymes since it provides a positive route to evaluate the activity of a given enzyme in dynamic and inversible regulation of targeting cellular processes.
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Affiliation(s)
- Jizhong Zhao
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hongmei Hu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Hongling Zhou
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jingwen Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Li Wang
- Wuhan No.1 Hospital, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Rui Wang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Shenzhen Huazhong University of Science and Technology Research Institute, Shenzhen, Guangdong, 518057, China.
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19
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Skeens E, Sinha S, Ahsan M, D'Ordine AM, Jogl G, Palermo G, Lisi GP. High-Fidelity, Hyper-Accurate, and Evolved Mutants Rewire Atomic Level Communication in CRISPR-Cas9. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.25.554853. [PMID: 37662375 PMCID: PMC10473742 DOI: 10.1101/2023.08.25.554853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
The Cas9-HF1, HypaCas9, and evoCas9 variants of the Cas9 endonuclease are critical tools to mitigate off-target effects in the application of CRISPR-Cas9 technology. The mechanisms by which mutations in the Rec3 domain mediate specificity in these variants are poorly understood. Here, solution NMR and molecular dynamics simulations establish the structural and dynamic effects of high-specificity mutations in Rec3, and how they propagate the allosteric signal of Cas9. We reveal conserved structural changes and peculiar dynamic differences at regions of Rec3 that interface with the RNA:DNA hybrid, transducing chemical signals from Rec3 to the catalytic HNH domain. The variants remodel the communication sourcing from the Rec3 α-helix 37, previously shown to sense target DNA complementarity, either directly or allosterically. This mechanism increases communication between the DNA mismatch recognition helix and the HNH active site, shedding light on the structure and dynamics underlying Cas9 specificity and providing insight for future engineering principles.
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20
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Sinha S, Pindi C, Ahsan M, Arantes PR, Palermo G. Machines on Genes through the Computational Microscope. J Chem Theory Comput 2023; 19:1945-1964. [PMID: 36947696 PMCID: PMC10104023 DOI: 10.1021/acs.jctc.2c01313] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2023]
Abstract
Macromolecular machines acting on genes are at the core of life's fundamental processes, including DNA replication and repair, gene transcription and regulation, chromatin packaging, RNA splicing, and genome editing. Here, we report the increasing role of computational biophysics in characterizing the mechanisms of "machines on genes", focusing on innovative applications of computational methods and their integration with structural and biophysical experiments. We showcase how state-of-the-art computational methods, including classical and ab initio molecular dynamics to enhanced sampling techniques, and coarse-grained approaches are used for understanding and exploring gene machines for real-world applications. As this review unfolds, advanced computational methods describe the biophysical function that is unseen through experimental techniques, accomplishing the power of the "computational microscope", an expression coined by Klaus Schulten to highlight the extraordinary capability of computer simulations. Pushing the frontiers of computational biophysics toward a pragmatic representation of large multimegadalton biomolecular complexes is instrumental in bridging the gap between experimentally obtained macroscopic observables and the molecular principles playing at the microscopic level. This understanding will help harness molecular machines for medical, pharmaceutical, and biotechnological purposes.
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Affiliation(s)
- Souvik Sinha
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
| | - Chinmai Pindi
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
| | - Mohd Ahsan
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
| | - Pablo R. Arantes
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
| | - Giulia Palermo
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
- Department of Chemistry, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
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21
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Nierzwicki Ł, Ahsan M, Palermo G. The Electronic Structure of Genome Editors from the First Principles. ELECTRONIC STRUCTURE (BRISTOL, ENGLAND) 2023; 5:014003. [PMID: 36926635 PMCID: PMC10016068 DOI: 10.1088/2516-1075/acb410] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Genome editing based on the CRISPR-Cas9 system has paved new avenues for medicine, pharmaceutics, biotechnology, and beyond. This article reports the role of first-principles (ab-initio) molecular dynamics (MD) in the CRISPR-Cas9 revolution, achieving a profound understanding of the enzymatic function and offering valuable insights for enzyme engineering. We introduce the methodologies and explain the use of ab-initio MD simulations to characterize the two-metal dependent mechanism of DNA cleavage in the RuvC domain of the Cas9 enzyme, and how a second catalytic domain, HNH, cleaves the target DNA with the aid of a single metal ion. A detailed description of how ab-initio MD is combined with free-energy methods - i.e., thermodynamic integration and metadynamics - to break and form chemical bonds is given, explaining the use of these methods to determine the chemical landscape and establish the catalytic mechanism in CRISPR-Cas9. The critical role of classical methods is also discussed, explaining theory and application of constant pH MD simulations, used to accurately predict the catalytic residues' protonation states. Overall, first-principles methods are shown to unravel the electronic structure of the Cas9 enzyme, providing valuable insights that can serve for the design of genome editing tools with improved catalytic efficiency or controllable activity.
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Affiliation(s)
- Łukasz Nierzwicki
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
| | - Mohd Ahsan
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
| | - Giulia Palermo
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
- Department of Chemistry, University of California Riverside, 900 University Avenue, Riverside, CA 52512, United States
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22
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Bhattacharya S, Satpati P. Insights into the Mechanism of CRISPR/Cas9-Based Genome Editing from Molecular Dynamics Simulations. ACS OMEGA 2023; 8:1817-1837. [PMID: 36687047 PMCID: PMC9850488 DOI: 10.1021/acsomega.2c05583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
The CRISPR/Cas9 system is a popular genome-editing tool with immense therapeutic potential. It is a simple two-component system (Cas9 protein and RNA) that recognizes the DNA sequence on the basis of RNA:DNA complementarity, and the Cas9 protein catalyzes the double-stranded break in the DNA. In the past decade, near-atomic resolution structures at various stages of the CRISPR/Cas9 DNA editing pathway have been reported along with numerous experimental and computational studies. Such studies have boosted knowledge of the genome-editing mechanism. Despite such advancements, the application of CRISPR/Cas9 in therapeutics is still limited, primarily due to off-target effects. Several studies aim at engineering high-fidelity Cas9 to minimize the off-target effects. Molecular Dynamics (MD) simulations have been an excellent complement to the experimental studies for investigating the mechanism of CRISPR/Cas9 editing in terms of structure, thermodynamics, and kinetics. MD-based studies have uncovered several important molecular aspects of Cas9, such as nucleotide binding, catalytic mechanism, and off-target effects. In this Review, the contribution of MD simulation to understand the CRISPR/Cas9 mechanism has been discussed, preceded by an overview of the history, mechanism, and structural aspects of the CRISPR/Cas9 system. These studies are important for the rational design of highly specific Cas9 and will also be extremely promising for achieving more accurate genome editing in the future.
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Affiliation(s)
- Shreya Bhattacharya
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
| | - Priyadarshi Satpati
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India
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23
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Wang J, Arantes PR, Ahsan M, Sinha S, Kyro GW, Maschietto F, Allen B, Skeens E, Lisi GP, Batista VS, Palermo G. Twisting and swiveling domain motions in Cas9 to recognize target DNA duplexes, make double-strand breaks, and release cleaved duplexes. Front Mol Biosci 2023; 9:1072733. [PMID: 36699705 PMCID: PMC9868570 DOI: 10.3389/fmolb.2022.1072733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 12/12/2022] [Indexed: 01/11/2023] Open
Abstract
The CRISPR-associated protein 9 (Cas9) has been engineered as a precise gene editing tool to make double-strand breaks. CRISPR-associated protein 9 binds the folded guide RNA (gRNA) that serves as a binding scaffold to guide it to the target DNA duplex via a RecA-like strand-displacement mechanism but without ATP binding or hydrolysis. The target search begins with the protospacer adjacent motif or PAM-interacting domain, recognizing it at the major groove of the duplex and melting its downstream duplex where an RNA-DNA heteroduplex is formed at nanomolar affinity. The rate-limiting step is the formation of an R-loop structure where the HNH domain inserts between the target heteroduplex and the displaced non-target DNA strand. Once the R-loop structure is formed, the non-target strand is rapidly cleaved by RuvC and ejected from the active site. This event is immediately followed by cleavage of the target DNA strand by the HNH domain and product release. Within CRISPR-associated protein 9, the HNH domain is inserted into the RuvC domain near the RuvC active site via two linker loops that provide allosteric communication between the two active sites. Due to the high flexibility of these loops and active sites, biophysical techniques have been instrumental in characterizing the dynamics and mechanism of the CRISPR-associated protein 9 nucleases, aiding structural studies in the visualization of the complete active sites and relevant linker structures. Here, we review biochemical, structural, and biophysical studies on the underlying mechanism with emphasis on how CRISPR-associated protein 9 selects the target DNA duplex and rejects non-target sequences.
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Affiliation(s)
- Jimin Wang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Pablo R. Arantes
- Department of Bioengineering and Department of Chemistry, University of California, Riverside, Riverside, CA, United States
| | - Mohd Ahsan
- Department of Bioengineering and Department of Chemistry, University of California, Riverside, Riverside, CA, United States
| | - Souvik Sinha
- Department of Bioengineering and Department of Chemistry, University of California, Riverside, Riverside, CA, United States
| | - Gregory W. Kyro
- Department of Chemistry, Yale University, New Haven, CT, United States
| | | | - Brandon Allen
- Department of Chemistry, Yale University, New Haven, CT, United States
| | - Erin Skeens
- Department of Molecular and Cell Biology and Biochemistry, Brown University, Providence, RI, United States
| | - George P. Lisi
- Department of Molecular and Cell Biology and Biochemistry, Brown University, Providence, RI, United States
| | - Victor S. Batista
- Department of Chemistry, Yale University, New Haven, CT, United States
| | - Giulia Palermo
- Department of Bioengineering and Department of Chemistry, University of California, Riverside, Riverside, CA, United States
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24
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Bravo JP, Hibshman GN, Taylor DW. Constructing next-generation CRISPR-Cas tools from structural blueprints. Curr Opin Biotechnol 2022; 78:102839. [PMID: 36371895 DOI: 10.1016/j.copbio.2022.102839] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/18/2022] [Accepted: 10/10/2022] [Indexed: 11/12/2022]
Abstract
Clustered regularly interspaced short palindromic repeats - CRISPR-associated protein (CRISPR-Cas) systems are a critical component of the bacterial adaptive immune response. Since the discovery that they can be reengineered as programmable RNA-guided nucleases, there has been significant interest in using these systems to perform diverse and precise genetic manipulations. Here, we outline recent advances in the mechanistic understanding of CRISPR-Cas9, how these findings have been leveraged in the rational redesign of Cas9 variants with altered activities, and how these novel tools can be exploited for biotechnology and therapeutics. We also discuss the potential of the ubiquitous, yet often-overlooked, multisubunit CRISPR effector complexes for large-scale genomic deletions. Furthermore, we highlight how future structural studies will bolster these technologies.
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Affiliation(s)
- Jack Pk Bravo
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA.
| | - Grace N Hibshman
- Interdisciplinary Life Sciences Graduate Program, The University of Texas at Austin, Austin, TX, USA
| | - David W Taylor
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, USA; Interdisciplinary Life Sciences Graduate Program, The University of Texas at Austin, Austin, TX, USA; Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX, USA; Livestrong Cancer Institutes, Dell Medical School, Austin, TX, USA
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25
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Pokorná P, Krepl M, Campagne S, Šponer J. Conformational Heterogeneity of RNA Stem-Loop Hairpins Bound to FUS-RNA Recognition Motif with Disordered RGG Tail Revealed by Unbiased Molecular Dynamics Simulations. J Phys Chem B 2022; 126:9207-9221. [PMID: 36348631 DOI: 10.1021/acs.jpcb.2c06168] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
RNA-protein complexes use diverse binding strategies, ranging from structurally well-defined interfaces to completely disordered regions. Experimental characterization of flexible segments is challenging and can be aided by atomistic molecular dynamics (MD) simulations. Here, we used an extended set of microsecond-scale MD trajectories (400 μs in total) to study two FUS-RNA constructs previously characterized by nuclear magnetic resonance (NMR) spectroscopy. The FUS protein contains a well-structured RNA recognition motif domain followed by a presumably disordered RGG tail that binds RNA stem-loop hairpins. Our simulations not only provide several suggestions complementing the experiments but also reveal major methodological difficulties in studies of such complex RNA-protein interfaces. Despite efforts to stabilize the binding via system-specific force-field adjustments, we have observed progressive distortions of the RNA-protein interface inconsistent with experimental data. We propose that the dynamics is so rich that its converged description is not achievable even upon stabilizing the system. Still, after careful analysis of the trajectories, we have made several suggestions regarding the binding. We identify substates in the RNA loops, which can explain the NMR data. The RGG tail localized in the minor groove remains disordered, sampling countless transient interactions with the RNA. There are long-range couplings among the different elements contributing to the recognition, which can lead to allosteric communication throughout the system. Overall, the RNA-FUS systems form dynamical ensembles that cannot be fully represented by single static structures. Thus, albeit imperfect, MD simulations represent a viable tool to investigate dynamic RNA-protein complexes.
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Affiliation(s)
- Pavlína Pokorná
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic.,National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Miroslav Krepl
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Sébastien Campagne
- INSERM U1212, CNRS UMR 5320, ARNA Laboratory, University of Bordeaux, 146 rue Léo Saignat, 33076 Bordeaux Cedex, France
| | - Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
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26
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Pacesa M, Lin CH, Cléry A, Saha A, Arantes PR, Bargsten K, Irby MJ, Allain FHT, Palermo G, Cameron P, Donohoue PD, Jinek M. Structural basis for Cas9 off-target activity. Cell 2022; 185:4067-4081.e21. [PMID: 36306733 PMCID: PMC10103147 DOI: 10.1016/j.cell.2022.09.026] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 07/01/2022] [Accepted: 09/15/2022] [Indexed: 11/06/2022]
Abstract
The target DNA specificity of the CRISPR-associated genome editor nuclease Cas9 is determined by complementarity to a 20-nucleotide segment in its guide RNA. However, Cas9 can bind and cleave partially complementary off-target sequences, which raises safety concerns for its use in clinical applications. Here, we report crystallographic structures of Cas9 bound to bona fide off-target substrates, revealing that off-target binding is enabled by a range of noncanonical base-pairing interactions within the guide:off-target heteroduplex. Off-target substrates containing single-nucleotide deletions relative to the guide RNA are accommodated by base skipping or multiple noncanonical base pairs rather than RNA bulge formation. Finally, PAM-distal mismatches result in duplex unpairing and induce a conformational change in the Cas9 REC lobe that perturbs its conformational activation. Together, these insights provide a structural rationale for the off-target activity of Cas9 and contribute to the improved rational design of guide RNAs and off-target prediction algorithms.
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Affiliation(s)
- Martin Pacesa
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Chun-Han Lin
- Caribou Biosciences, 2929 Seventh Street Suite 105, Berkeley, CA 94710, USA
| | - Antoine Cléry
- Institute of Biochemistry, ETH Zurich, Hönggerbergring 64, 8093 Zurich, Switzerland
| | - Aakash Saha
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, USA
| | - Pablo R Arantes
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, USA
| | - Katja Bargsten
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Matthew J Irby
- Caribou Biosciences, 2929 Seventh Street Suite 105, Berkeley, CA 94710, USA
| | - Frédéric H-T Allain
- Institute of Biochemistry, ETH Zurich, Hönggerbergring 64, 8093 Zurich, Switzerland
| | - Giulia Palermo
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 52512, USA
| | - Peter Cameron
- Caribou Biosciences, 2929 Seventh Street Suite 105, Berkeley, CA 94710, USA
| | - Paul D Donohoue
- Caribou Biosciences, 2929 Seventh Street Suite 105, Berkeley, CA 94710, USA
| | - Martin Jinek
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
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27
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Daskalakis V. Deciphering the QR Code of the CRISPR-Cas9 System: Synergy between Gln768 (Q) and Arg976 (R). ACS PHYSICAL CHEMISTRY AU 2022; 2:496-505. [PMID: 36855610 PMCID: PMC9955204 DOI: 10.1021/acsphyschemau.2c00041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 10/14/2022]
Abstract
Markov state models (MSMs) and machine learning (ML) algorithms can extrapolate the long-time-scale behavior of large biomolecules from molecular dynamics (MD) trajectories. In this study, an MD-MSM-ML scheme has been applied to probe the large endonuclease (Cas9) in the bacterial adaptive immunity CRISPR-Cas9 system. CRISPR has become a programmable and state-of-the-art powerful genome editing tool that has already revolutionized life sciences. CRISPR-Cas9 is programmed to process specific DNA sequences in the genome. However, human/biomedical applications are compromised by off-target DNA damage. Characterization of Cas9 at the structural and biophysical levels is a prerequisite for the development of efficient and high-fidelity Cas9 variants. The Cas9 wild type and two variants (R63A-R66A-R70A, R69A-R71A-R74A-R78A) are studied herein. The configurational space of Cas9 is provided with a focus on the conformations of the side chains of two residues (Gln768 and Arg976). A model for the synergy between those two residues is proposed. The results are discussed within the context of experimental literature. The results and methodology can be exploited for the study of large biomolecules in general and for the engineering of more efficient and safer Cas9 variants for applications.
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28
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Langmüller AM, Champer J, Lapinska S, Xie L, Metzloff M, Champer SE, Liu J, Xu Y, Du J, Clark AG, Messer PW. Fitness effects of CRISPR endonucleases in Drosophila melanogaster populations. eLife 2022; 11:e71809. [PMID: 36135925 PMCID: PMC9545523 DOI: 10.7554/elife.71809] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/08/2022] [Indexed: 11/13/2022] Open
Abstract
Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 provides a highly efficient and flexible genome editing technology with numerous potential applications ranging from gene therapy to population control. Some proposed applications involve the integration of CRISPR/Cas9 endonucleases into an organism's genome, which raises questions about potentially harmful effects to the transgenic individuals. One example for which this is particularly relevant are CRISPR-based gene drives conceived for the genetic alteration of entire populations. The performance of such drives can strongly depend on fitness costs experienced by drive carriers, yet relatively little is known about the magnitude and causes of these costs. Here, we assess the fitness effects of genomic CRISPR/Cas9 expression in Drosophila melanogaster cage populations by tracking allele frequencies of four different transgenic constructs that allow us to disentangle 'direct' fitness costs due to the integration, expression, and target-site activity of Cas9, from fitness costs due to potential off-target cleavage. Using a maximum likelihood framework, we find that a model with no direct fitness costs but moderate costs due to off-target effects fits our cage data best. Consistent with this, we do not observe fitness costs for a construct with Cas9HF1, a high-fidelity version of Cas9. We further demonstrate that using Cas9HF1 instead of standard Cas9 in a homing drive achieves similar drive conversion efficiency. These results suggest that gene drives should be designed with high-fidelity endonucleases and may have implications for other applications that involve genomic integration of CRISPR endonucleases.
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Affiliation(s)
- Anna M Langmüller
- Department of Computational Biology, Cornell UniversityIthacaUnited States
- Institut für Populationsgenetik, Vetmeduni ViennaViennaAustria
- Vienna Graduate School of Population Genetics, Vetmeduni ViennaViennaAustria
| | - Jackson Champer
- Department of Computational Biology, Cornell UniversityIthacaUnited States
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
- Center for Bioinformatics, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking UniversityBeijingChina
| | - Sandra Lapinska
- Department of Computational Biology, Cornell UniversityIthacaUnited States
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
| | - Lin Xie
- Department of Computational Biology, Cornell UniversityIthacaUnited States
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
| | - Matthew Metzloff
- Department of Computational Biology, Cornell UniversityIthacaUnited States
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
| | - Samuel E Champer
- Department of Computational Biology, Cornell UniversityIthacaUnited States
| | - Jingxian Liu
- Department of Computational Biology, Cornell UniversityIthacaUnited States
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
| | - Yineng Xu
- Department of Computational Biology, Cornell UniversityIthacaUnited States
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
| | - Jie Du
- Center for Bioinformatics, School of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking UniversityBeijingChina
| | - Andrew G Clark
- Department of Computational Biology, Cornell UniversityIthacaUnited States
- Department of Molecular Biology and Genetics, Cornell UniversityIthacaUnited States
| | - Philipp W Messer
- Department of Computational Biology, Cornell UniversityIthacaUnited States
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29
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Vora DS, Verma Y, Sundar D. A Machine Learning Approach to Identify the Importance of Novel Features for CRISPR/Cas9 Activity Prediction. Biomolecules 2022; 12:1123. [PMID: 36009017 PMCID: PMC9405635 DOI: 10.3390/biom12081123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 11/23/2022] Open
Abstract
The reprogrammable CRISPR/Cas9 genome editing tool's growing popularity is hindered by unwanted off-target effects. Efforts have been directed toward designing efficient guide RNAs as well as identifying potential off-target threats, yet factors that determine efficiency and off-target activity remain obscure. Based on sequence features, previous machine learning models performed poorly on new datasets, thus there is a need for the incorporation of novel features. The binding energy estimation of the gRNA-DNA hybrid as well as the Cas9-gRNA-DNA hybrid allowed generating better performing machine learning models for the prediction of Cas9 activity. The analysis of feature contribution towards the model output on a limited dataset indicated that energy features played a determining role along with the sequence features. The binding energy features proved essential for the prediction of on-target activity and off-target sites. The plateau, in the performance on unseen datasets, of current machine learning models could be overcome by incorporating novel features, such as binding energy, among others. The models are provided on GitHub (GitHub Inc., San Francisco, CA, USA).
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Affiliation(s)
- Dhvani Sandip Vora
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Yugesh Verma
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
| | - Durai Sundar
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
- Yardi School of Artificial Intelligence, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India
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30
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Copeland M, Do HN, Votapka L, Joshi K, Wang J, Amaro RE, Miao Y. Gaussian Accelerated Molecular Dynamics in OpenMM. J Phys Chem B 2022; 126:5810-5820. [PMID: 35895977 PMCID: PMC9773147 DOI: 10.1021/acs.jpcb.2c03765] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Gaussian accelerated molecular dynamics (GaMD) is a computational technique that provides both unconstrained enhanced sampling and free energy calculations of biomolecules. Here, we present the implementation of GaMD in the OpenMM simulation package and validate it on model systems of alanine dipeptide and RNA folding. For alanine dipeptide, 30 ns GaMD production simulations reproduced free energy profiles of 1000 ns conventional molecular dynamics (cMD) simulations. In addition, GaMD simulations captured the folding pathways of three hyperstable RNA tetraloops (UUCG, GCAA, and CUUG) and binding of the rbt203 ligand to the HIV-1 Tar RNA, both of which involved critical electrostatic interactions such as hydrogen bonding and base stacking. Together with previous implementations, GaMD in OpenMM will allow for wider applications in simulations of proteins, RNA, and other biomolecules.
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Affiliation(s)
- Matthew Copeland
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66047
| | - Hung N. Do
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66047
| | - Lane Votapka
- Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093
| | - Keya Joshi
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66047
| | - Jinan Wang
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66047
| | - Rommie E. Amaro
- Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093
| | - Yinglong Miao
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS 66047,To whom correspondence should be addressed:
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31
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Saha A, Arantes PR, Palermo G. Dynamics and mechanisms of CRISPR-Cas9 through the lens of computational methods. Curr Opin Struct Biol 2022; 75:102400. [PMID: 35689914 PMCID: PMC9398989 DOI: 10.1016/j.sbi.2022.102400] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/25/2022] [Accepted: 05/07/2022] [Indexed: 12/24/2022]
Abstract
The clustered regularly interspaced short palindromic repeat (CRISPR) genome-editing revolution established the beginning of a new era in life sciences. Here, we review the role of state-of-the-art computations in the CRISPR-Cas9 revolution, from the early refinement of cryo-EM data to enhanced simulations of large-scale conformational transitions. Molecular simulations reported a mechanism for RNA binding and the formation of a catalytically competent Cas9 enzyme, in agreement with subsequent structural studies. Inspired by single-molecule experiments, molecular dynamics offered a rationale for the onset of off-target effects, while graph theory unveiled the allosteric regulation. Finally, the use of a mixed quantum-classical approach established the catalytic mechanism of DNA cleavage. Overall, molecular simulations have been instrumental in understanding the dynamics and mechanism of CRISPR-Cas9, contributing to understanding function, catalysis, allostery, and specificity.
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Affiliation(s)
- Aakash Saha
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA, 52512, United States. https://twitter.com/@aakashsahha
| | - Pablo R Arantes
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA, 52512, United States. https://twitter.com/@pablitoarantes
| | - Giulia Palermo
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA, 52512, United States; Department of Chemistry, University of California Riverside, 900 University Avenue, Riverside, CA, 52512, United States.
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32
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Vora DS, Jaiswal AK, Sundar D. Implementing accelerated dynamics to unravel the effects of high-fidelity Cas9 mutants on target DNA and guide RNA hybrid stability. J Biomol Struct Dyn 2022:1-13. [PMID: 35882048 DOI: 10.1080/07391102.2022.2103032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The clustered regularly interspersed short palindromic repeats (CRISPR) and its associated nuclease (Cas9) offers a unique and easily reprogrammable system for editing eukaryotic genomes. Cas9 is guided to the target by an RNA strand, and precise edits are created by introducing double-stranded breaks. However, nuclease activity of Cas9 is also triggered at other sites other than the target sit, which is a major limitation for various applications. Cas9 variants have been designed to improve the efficacy of the tool by introducing certain mutations. However, the on-target activity of such Cas9 variants is often seen as compromised. Hence, understanding the sub-molecular differences in the variants is essential to elucidate the factors that contribute to efficiency. The study reveals distortions in the PAM-distal regions of the nucleic hybrids as well as changes in the interactions between the Cas9 variants and RNA-DNA hybrid, contributing to the explanation for differences in on-target activity.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Dhvani Sandip Vora
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology (IIT) Delhi, New Delhi, India
| | - Atul Kumar Jaiswal
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology (IIT) Delhi, New Delhi, India
| | - Durai Sundar
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology (IIT) Delhi, New Delhi, India.,Yardi School of Artificial Intelligence, Indian Institute of Technology (IIT) Delhi, New Delhi, India
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33
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Talluri S. Engineering and Design of Programmable Genome Editors. J Phys Chem B 2022; 126:5140-5150. [PMID: 35819243 DOI: 10.1021/acs.jpcb.2c03761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Programmable genome editors are enzymes that can be targeted to a specific location in the genome for making site-specific alterations or deletions. The engineering, design, and development of sequence-specific editors has resulted in a dramatic increase in the precision of editing for nucleotide sequences. These editors can target specific locations in a genome, in vivo. The genome editors are being deployed for the development of genetically modified organisms for agriculture and industry, and for gene therapy of inherited human genetic disorders, cancer, and immunotherapy. Experimental and computational studies of structure, binding, activity, dynamics, and folding, reviewed here, have provided valuable insights that have the potential for increasing the functional efficiency of these gene/genome editors. Biochemical and biophysical studies of the specificities of natural and engineered genome editors reveal that increased binding affinity can be detrimental because of the increase of off-target effects and that the engineering and design of genome editors with higher specificity may require modulation and control of the conformational dynamics.
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Affiliation(s)
- Sekhar Talluri
- Department of Biotechnology, GITAM, Visakhapatnam, India 530045
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34
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Chen Q, Chuai G, Zhang C, Zhang Q, Liu Q. Toward a molecular mechanism-based prediction of CRISPR-Cas9 targeting effects. Sci Bull (Beijing) 2022; 67:1201-1204. [PMID: 36546144 DOI: 10.1016/j.scib.2022.04.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Qinchang Chen
- Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine, Shanghai East Hospital, Bioinformatics Department, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China; Shanghai Research Institute for Intelligent Autonomous Systems, Shanghai 201210, China
| | - Guohui Chuai
- Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine, Shanghai East Hospital, Bioinformatics Department, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China; Shanghai Research Institute for Intelligent Autonomous Systems, Shanghai 201210, China
| | - Chao Zhang
- Department of Plastic and Reconstructive Surgery, Shanghai Institute of Precision Medicine, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
| | - Qing Zhang
- Roche Pharma Research and Early Development, pRED Informatics, Roche Innovation Center Shanghai, Roche R&D Center (China) Ltd., Shanghai 201203, China.
| | - Qi Liu
- Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine, Shanghai East Hospital, Bioinformatics Department, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China; Shanghai Research Institute for Intelligent Autonomous Systems, Shanghai 201210, China.
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35
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Pawnikar S, Miao Y. Mechanism of Peptide Agonist Binding in CXCR4 Chemokine Receptor. Front Mol Biosci 2022; 9:821055. [PMID: 35359589 PMCID: PMC8963245 DOI: 10.3389/fmolb.2022.821055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/14/2022] [Indexed: 01/07/2023] Open
Abstract
Chemokine receptors are key G-protein-coupled receptors (GPCRs) that control cell migration in immune system responses, development of cardiovascular and central nervous systems, and numerous diseases. In particular, the CXCR4 chemokine receptor promotes metastasis, tumor growth and angiogenesis in cancers. CXCR4 is also used as one of the two co-receptors for T-tropic HIV-1 entry into host cells. Therefore, CXCR4 serves as an important therapeutic target for treating cancers and HIV infection. Apart from the CXCL12 endogenous peptide agonist, previous studies suggested that the first 17 amino acids of CXCL12 are sufficient to activate CXCR4. Two 17-residue peptides with positions 1-4 mutated to RSVM and ASLW functioned as super and partial agonists of CXCR4, respectively. However, the mechanism of peptide agonist binding in CXCR4 remains unclear. Here, we have investigated this mechanism through all-atom simulations using a novel Peptide Gaussian accelerated molecular dynamics (Pep-GaMD) method. The Pep-GaMD simulations have allowed us to explore representative binding conformations of each peptide and identify critical low-energy states of CXCR4 activated by the super versus partial peptide agonists. Our simulations have provided important mechanistic insights into peptide agonist binding in CXCR4, which are expected to facilitate rational design of new peptide modulators of CXCR4 and other chemokine receptors.
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36
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Do HN, Wang J, Bhattarai A, Miao Y. GLOW: A Workflow Integrating Gaussian-Accelerated Molecular Dynamics and Deep Learning for Free Energy Profiling. J Chem Theory Comput 2022; 18:1423-1436. [PMID: 35200019 PMCID: PMC9773012 DOI: 10.1021/acs.jctc.1c01055] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We introduce a Gaussian-accelerated molecular dynamics (GaMD), deep learning (DL), and free energy profiling workflow (GLOW) to predict molecular determinants and map free energy landscapes of biomolecules. All-atom GaMD-enhanced sampling simulations are first performed on biomolecules of interest. Structural contact maps are then calculated from GaMD simulation frames and transformed into images for building DL models using a convolutional neural network. Important structural contacts are further determined from DL models of attention maps of the structural contact gradients, which allow us to identify the system reaction coordinates. Finally, free energy profiles are calculated for the selected reaction coordinates through energetic reweighting of the GaMD simulations. We have also successfully demonstrated GLOW for the characterization of activation and allosteric modulation of a G protein-coupled receptor, using the adenosine A1 receptor (A1AR) as a model system. GLOW findings are highly consistent with previous experimental and computational studies of the A1AR, while also providing further mechanistic insights into the receptor function. In summary, GLOW provides a systematic approach to mapping free energy landscapes of biomolecules. The GLOW workflow and its user manual can be downloaded at http://miaolab.org/GLOW.
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Affiliation(s)
- Hung N. Do
- The Center for Computational Biology and Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66047
| | - Jinan Wang
- The Center for Computational Biology and Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66047
| | - Apurba Bhattarai
- The Center for Computational Biology and Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66047
| | - Yinglong Miao
- The Center for Computational Biology and Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas 66047,Corresponding author:
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37
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Size and surface coverage density are major factors in determining thiol modified gold nanoparticles characteristics. COMPUT THEOR CHEM 2022. [DOI: 10.1016/j.comptc.2021.113581] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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38
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Roy RK, Debashree I, Srivastava S, Rishi N, Srivastava A. CRISPR/ Cas9 Off-targets: Computational Analysis of Causes, Prediction,
Detection, and Overcoming Strategies. Curr Bioinform 2022. [DOI: 10.2174/1574893616666210708150439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
:
CRISPR/Cas9 technology is a highly flexible RNA-guided endonuclease (RGEN)
based gene-editing tool that has transformed the field of genomics, gene therapy, and genome/
epigenome imaging. Its wide range of applications provides immense scope for understanding
as well as manipulating genetic/epigenetic elements. However, the RGEN is prone to
off-target mutagenesis that leads to deleterious effects. This review details the molecular and cellular
mechanisms underlying the off-target activity, various available detection tools and prediction
methodology ranging from sequencing to machine learning approaches, and the strategies to
overcome/minimise off-targets. A coherent and concise method increasing target precision would
prove indispensable to concrete manipulation and interpretation of genome editing results that
can revolutionise therapeutics, including clarity in genome regulatory mechanisms during development.
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Affiliation(s)
- Roshan Kumar Roy
- Amity Institute of Virology and Immunology, Amity University Uttar Pradesh, Noida 201313, India
| | - Ipsita Debashree
- Amity Institute of Virology and Immunology, Amity University Uttar Pradesh, Noida 201313, India
| | - Sonal Srivastava
- Amity Institute of Virology and Immunology, Amity University Uttar Pradesh, Noida 201313,India
| | - Narayan Rishi
- Amity Institute of Virology and Immunology, Amity University Uttar Pradesh, Noida 201313,India
| | - Ashish Srivastava
- Amity Institute of Virology and Immunology, Amity University Uttar Pradesh, Noida 201313,India
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Pawnikar S, Bhattarai A, Wang J, Miao Y. Binding Analysis Using Accelerated Molecular Dynamics Simulations and Future Perspectives. Adv Appl Bioinform Chem 2022; 15:1-19. [PMID: 35023931 PMCID: PMC8747661 DOI: 10.2147/aabc.s247950] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 02/20/2021] [Indexed: 12/12/2022] Open
Abstract
Biomolecular recognition such as binding of small molecules, nucleic acids, peptides and proteins to their target receptors plays key roles in cellular function and has been targeted for therapeutic drug design. Molecular dynamics (MD) is a computational approach to analyze these binding processes at an atomistic level, which provides valuable understandings of the mechanisms of biomolecular recognition. However, the rather slow biomolecular binding events often present challenges for conventional MD (cMD), due to limited simulation timescales (typically over hundreds of nanoseconds to tens of microseconds). In this regard, enhanced sampling methods, particularly accelerated MD (aMD), have proven useful to bridge the gap and enable all-atom simulations of biomolecular binding events. Here, we will review the recent method developments of Gaussian aMD (GaMD), ligand GaMD (LiGaMD) and peptide GaMD (Pep-GaMD), which have greatly expanded our capabilities to simulate biomolecular binding processes. Spontaneous binding of various biomolecules to their receptors has been successfully simulated by GaMD. Microsecond LiGaMD and Pep-GaMD simulations have captured repetitive binding and dissociation of small-molecule ligands and highly flexible peptides, and thus enabled ligand/peptide binding thermodynamics and kinetics calculations. We will also present relevant application studies in simulations of important drug targets and future perspectives for rational computer-aided drug design.
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Affiliation(s)
- Shristi Pawnikar
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Apurba Bhattarai
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Jinan Wang
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Yinglong Miao
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
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40
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Zhao J, Hu H, Zhang J, Li Y, Wang L, Zhou H, Wang R. Endogenous hydrogen peroxide can efficiently regulate CRISPR-Cas9 based gene editing. NEW J CHEM 2022. [DOI: 10.1039/d1nj04203c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report controllable gene editing tools for the CRISPR-Cas9 system via genetic code expansion triggered by oxidative small molecule H2O2.
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Affiliation(s)
- Jizhong Zhao
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Hongmei Hu
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Jingwen Zhang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Yuanyuan Li
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Li Wang
- Wuhan No. 1 Hospital, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China
| | - Hongling Zhou
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Rui Wang
- Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
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Abstract
:
Clustered regularly interspaced short palindromic repeats along with CRISPR-associated protein
mechanisms preserve the memory of previous experiences with DNA invaders, in particular spacers
that are embedded in CRISPR arrays between coordinate repeats. There has been a fast progression in
the comprehension of this immune system and its implementations; however, there are numerous points
of view that anticipate explanations to make the field an energetic research zone. The efficiency of
CRISPR-Cas depends upon well-considered single guide RNA; for this purpose, many bioinformatics
methods and tools are created to support the design of greatly active and precise single guide RNA. Insilico
single guide RNA architecture is a crucial point for effective gene editing by means of the
CRISPR technique. Persistent attempts have been made to improve in-silico single guide RNA formulation
having great on-target effectiveness and decreased off-target effects. This review offers a summary
of the CRISPR computational tools to help different researchers pick a specific tool for their work according
to pros and cons, along with new thoughts to make new computational tools to overcome all existing
limitations.
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Affiliation(s)
- Mohsin Ali Nasir
- Center for Informational Biology, University of Electronic Science and Technology of China, No. 2006, Xiyuan Ave,
West Hi-Tech Zone, Chengdu 611731, China
| | - Samia Nawaz
- Center for Informational Biology, University of Electronic Science and Technology of China, No. 2006, Xiyuan Ave,
West Hi-Tech Zone, Chengdu 611731, China
| | - Jian Huang
- Center for Informational Biology, University of Electronic Science and Technology of China, No. 2006, Xiyuan Ave,
West Hi-Tech Zone, Chengdu 611731, China
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42
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Nierzwicki L, East KW, Morzan UN, Arantes PR, Batista VS, Lisi GP, Palermo G. Enhanced specificity mutations perturb allosteric signaling in CRISPR-Cas9. eLife 2021; 10:e73601. [PMID: 34908530 PMCID: PMC8741213 DOI: 10.7554/elife.73601] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 12/14/2021] [Indexed: 11/13/2022] Open
Abstract
CRISPR-Cas9 (clustered regularly interspaced short palindromic repeat and associated Cas9 protein) is a molecular tool with transformative genome editing capabilities. At the molecular level, an intricate allosteric signaling is critical for DNA cleavage, but its role in the specificity enhancement of the Cas9 endonuclease is poorly understood. Here, multi-microsecond molecular dynamics is combined with solution NMR and graph theory-derived models to probe the allosteric role of key specificity-enhancing mutations. We show that mutations responsible for increasing the specificity of Cas9 alter the allosteric structure of the catalytic HNH domain, impacting the signal transmission from the DNA recognition region to the catalytic sites for cleavage. Specifically, the K855A mutation strongly disrupts the allosteric connectivity of the HNH domain, exerting the highest perturbation on the signaling transfer, while K810A and K848A result in more moderate effects on the allosteric communication. This differential perturbation of the allosteric signal correlates to the order of specificity enhancement (K855A > K848A ~ K810A) observed in biochemical studies, with the mutation achieving the highest specificity most strongly perturbing the signaling transfer. These findings suggest that alterations of the allosteric communication from DNA recognition to cleavage are critical to increasing the specificity of Cas9 and that allosteric hotspots can be targeted through mutational studies for improving the system's function.
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Affiliation(s)
- Lukasz Nierzwicki
- Department of Bioengineering and Department of Chemistry, University of California, RiversideRiversideUnited States
| | - Kyle W East
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown UniversityProvidenceUnited States
| | - Uriel N Morzan
- International Centre for Theoretical PhysicsTriesteItaly
| | - Pablo R Arantes
- Department of Bioengineering and Department of Chemistry, University of California, RiversideRiversideUnited States
| | | | - George P Lisi
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown UniversityProvidenceUnited States
| | - Giulia Palermo
- Department of Bioengineering and Department of Chemistry, University of California, RiversideRiversideUnited States
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Wang J, Lan L, Wu X, Xu L, Miao Y. Mechanism of RNA recognition by a Musashi RNA-binding protein. Curr Res Struct Biol 2021; 4:10-20. [PMID: 34988468 PMCID: PMC8695263 DOI: 10.1016/j.crstbi.2021.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 10/31/2021] [Accepted: 12/07/2021] [Indexed: 12/21/2022] Open
Abstract
The Musashi RNA-binding proteins (RBPs) regulate translation of target mRNAs and maintenance of cell stemness and tumorigenesis. Musashi-1 (MSI1), long considered as an intestinal and neural stem cell marker, has been more recently found to be over expressed in many cancers. It has served as an important drug target for treating acute myeloid leukemia and solid tumors such as ovarian, colorectal and bladder cancer. One of the reported binding targets of MSI1 is Numb, a negative regulator of the Notch signaling. However, the dynamic mechanism of Numb RNA binding to MSI1 remains unknown, largely hindering effective drug design targeting this critical interaction. Here, we have performed extensive all-atom microsecond-timescale simulations using a robust Gaussian accelerated molecular dynamics (GaMD) method, which successfully captured multiple times of spontaneous and highly accurate binding of the Numb RNA from bulk solvent to the MSI1 protein target site. GaMD simulations revealed that Numb RNA binding to MSI1 involved largely induced fit in both the RNA and protein. The simulations also identified important low-energy intermediate conformational states during RNA binding, in which Numb interacted mainly with the β2-β3 loop and C terminus of MSI1. The mechanistic understanding of RNA binding obtained from our GaMD simulations is expected to facilitate rational structure-based drug design targeting MSI1 and other RBPs.
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Affiliation(s)
- Jinan Wang
- Center for Computational Biology, University of Kansas, Lawrence, KS, 66047, USA
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Lan Lan
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Xiaoqing Wu
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
| | - Liang Xu
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
- Department of Radiation Oncology, The University of Kansas Cancer Center, Kansas City, KS, 66160, USA
| | - Yinglong Miao
- Center for Computational Biology, University of Kansas, Lawrence, KS, 66047, USA
- Department of Molecular Biosciences, University of Kansas, Lawrence, KS, 66047, USA
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Li X, Wang C, Peng T, Chai Z, Ni D, Liu Y, Zhang J, Chen T, Lu S. Atomic-scale insights into allosteric inhibition and evolutional rescue mechanism of Streptococcus thermophilus Cas9 by the anti-CRISPR protein AcrIIA6. Comput Struct Biotechnol J 2021; 19:6108-6124. [PMID: 34900128 PMCID: PMC8632846 DOI: 10.1016/j.csbj.2021.11.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 12/26/2022] Open
Abstract
CRISPR-Cas systems are prokaryotic adaptive immunity against invading phages and plasmids. Phages have evolved diverse protein inhibitors of CRISPR-Cas systems, called anti-CRISPR (Acr) proteins, to neutralize this CRISPR machinery. In response, bacteria have co-evolved Cas variants to escape phage's anti-CRISPR strategies, called anti-anti-CRISPR systems. Here we explore the anti-CRISPR allosteric inhibition and anti-anti-CRISPR rescue mechanisms between Streptococcus thermophilus Cas9 (St1Cas9) and the anti-CRISPR protein AcrIIA6 at the atomic level, by generating mutants of key residues in St1Cas9. Extensive unbiased molecular dynamics simulations show that the functional motions of St1Cas9 in the presence of AcrIIA6 differ substantially from those of St1Cas9 alone. AcrIIA6 binding triggers a shift of St1Cas9 conformational ensemble towards a less catalytically competent state; this state significantly compromises protospacer adjacent motif (PAM) recognition and nuclease activity by altering interdependently conformational dynamics and allosteric signals among nuclease domains, PAM-interacting (PI) regions, and AcrIIA6 binding motifs. Via in vitro DNA cleavage assays, we further elucidate the rescue mechanism of efficiently escaping AcrIIA6 inhibition harboring St1Cas9 triple mutations (G993K/K1008M/K1010E) in the PI domain and identify the evolutionary landscape of such mutational escape within species. Our results provide mechanistic insights into Acr proteins as natural brakes for the CRISPR-Cas systems and a promising potential for the design of allosteric Acr peptidomimetics.
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Affiliation(s)
- Xinyi Li
- Department of Cardiology, Changzheng Hospital, Naval Medical University, Shanghai 200003, China
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Chengxiang Wang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Ting Peng
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Zongtao Chai
- Department of Hepatic Surgery VI, Eastern Hepatobiliary Surgery Hospital, Naval Medical University, Shanghai 200438, China
| | - Duan Ni
- The Charles Perkins Centre, University of Sydney, Sydney, NSW 2006, Australia
| | - Yaqin Liu
- Medicinal Chemistry and Bioinformatics Centre, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Jian Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
- Medicinal Chemistry and Bioinformatics Centre, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
| | - Ting Chen
- Department of Cardiology, Changzheng Hospital, Naval Medical University, Shanghai 200003, China
| | - Shaoyong Lu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
- Medicinal Chemistry and Bioinformatics Centre, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025, China
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45
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Donati E, Vidossich P, De Vivo M. Molecular Mechanism of Phosphate Steering for DNA Binding, Cleavage Localization, and Substrate Release in Nucleases. ACS Catal 2021. [DOI: 10.1021/acscatal.1c03346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Elisa Donati
- Laboratory of Molecular Modeling and Drug Discovery, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genoa, Italy
| | - Pietro Vidossich
- Laboratory of Molecular Modeling and Drug Discovery, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genoa, Italy
| | - Marco De Vivo
- Laboratory of Molecular Modeling and Drug Discovery, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genoa, Italy
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46
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Wang J, Arantes PR, Bhattarai A, Hsu RV, Pawnikar S, Huang YMM, Palermo G, Miao Y. Gaussian accelerated molecular dynamics (GaMD): principles and applications. WILEY INTERDISCIPLINARY REVIEWS. COMPUTATIONAL MOLECULAR SCIENCE 2021; 11:e1521. [PMID: 34899998 PMCID: PMC8658739 DOI: 10.1002/wcms.1521] [Citation(s) in RCA: 95] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 01/28/2021] [Indexed: 12/20/2022]
Abstract
Gaussian accelerated molecular dynamics (GaMD) is a robust computational method for simultaneous unconstrained enhanced sampling and free energy calculations of biomolecules. It works by adding a harmonic boost potential to smooth biomolecular potential energy surface and reduce energy barriers. GaMD greatly accelerates biomolecular simulations by orders of magnitude. Without the need to set predefined reaction coordinates or collective variables, GaMD provides unconstrained enhanced sampling and is advantageous for simulating complex biological processes. The GaMD boost potential exhibits a Gaussian distribution, thereby allowing for energetic reweighting via cumulant expansion to the second order (i.e., "Gaussian approximation"). This leads to accurate reconstruction of free energy landscapes of biomolecules. Hybrid schemes with other enhanced sampling methods, such as the replica exchange GaMD (rex-GaMD) and replica exchange umbrella sampling GaMD (GaREUS), have also been introduced, further improving sampling and free energy calculations. Recently, new "selective GaMD" algorithms including the ligand GaMD (LiGaMD) and peptide GaMD (Pep-GaMD) enabled microsecond simulations to capture repetitive dissociation and binding of small-molecule ligands and highly flexible peptides. The simulations then allowed highly efficient quantitative characterization of the ligand/peptide binding thermodynamics and kinetics. Taken together, GaMD and its innovative variants are applicable to simulate a wide variety of biomolecular dynamics, including protein folding, conformational changes and allostery, ligand binding, peptide binding, protein-protein/nucleic acid/carbohydrate interactions, and carbohydrate/nucleic acid interactions. In this review, we present principles of the GaMD algorithms and recent applications in biomolecular simulations and drug design.
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Affiliation(s)
- Jinan Wang
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, 2030 Becker Dr., Lawrence, KS, 66047, United States
| | - Pablo R Arantes
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92512, United States
| | - Apurba Bhattarai
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, 2030 Becker Dr, Lawrence, KS, 66047, United States
| | - Rohaine V Hsu
- Department of Bioengineering, University of California Riverside, 900 University Avenue, Riverside, CA 92512, United States
| | - Shristi Pawnikar
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, 2030 Becker Dr., Lawrence, KS, 66047, United States
| | - Yu-Ming M Huang
- Department of Physics & Astronomy, Wayne State University, 666 W Hancock St, Detroit, MI 48207, USA
| | - Giulia Palermo
- Department of Bioengineering and Department of Chemistry, University of California Riverside, 900 University Avenue, Riverside, CA 92512, United States
| | - Yinglong Miao
- Center for Computational Biology and Department of Molecular Biosciences, University of Kansas, 2030 Becker Dr., Lawrence, Kansas 66047, United States
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47
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Banerjee T, Takahashi H, Subekti DRG, Kamagata K. Engineering of the genome editing protein Cas9 to slide along DNA. Sci Rep 2021; 11:14165. [PMID: 34239016 PMCID: PMC8266852 DOI: 10.1038/s41598-021-93685-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 06/28/2021] [Indexed: 12/26/2022] Open
Abstract
The genome editing protein Cas9 faces engineering challenges in improving off-target DNA cleavage and low editing efficiency. In this study, we aimed to engineer Cas9 to be able to slide along DNA, which might facilitate genome editing and reduce off-target cleavage. We used two approaches to achieve this: reducing the sliding friction along DNA by removing the interactions of Cas9 residues with DNA and facilitating sliding by introducing the sliding-promoting tail of Nhp6A. Seven engineered mutants of Cas9 were prepared, and their performance was tested using single-molecule fluorescence microscopy. Comparison of the mutations enabled the identification of key residues of Cas9 to enhance the sliding along DNA in the presence and absence of single guide RNA (sgRNA). The attachment of the tail to Cas9 mutants enhanced sliding along DNA, particularly in the presence of sgRNA. Together, using the proposed approaches, the sliding ability of Cas9 was improved up to eightfold in the presence of sgRNA. A sliding model of Cas9 and its engineering action are discussed herein.
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Affiliation(s)
- Trishit Banerjee
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577, Japan
| | - Hiroto Takahashi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577, Japan
| | - Dwiky Rendra Graha Subekti
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577, Japan
| | - Kiyoto Kamagata
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577, Japan.
- Department of Chemistry, Graduate School of Science, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577, Japan.
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48
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Chen J, Wang L, Wang W, Sun H, Pang L, Bao H. Conformational transformation of switch domains in GDP/K-Ras induced by G13 mutants: An investigation through Gaussian accelerated molecular dynamics simulations and principal component analysis. Comput Biol Med 2021; 135:104639. [PMID: 34247129 DOI: 10.1016/j.compbiomed.2021.104639] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 07/05/2021] [Accepted: 07/05/2021] [Indexed: 10/20/2022]
Abstract
Mutations in K-Ras are involved in a large number of all human cancers, thus, K-Ras is regarded as a promising target for anticancer drug design. Understanding the target roles of K-Ras is important for providing insights on the molecular mechanism underlying the conformational transformation of the switch domains in K-Ras due to mutations. In this study, multiple replica Gaussian accelerated molecular (MR-GaMD) simulations and principal component analysis (PCA) were applied to probe the effect of G13A, G13D and G13I mutations on conformational transformations of the switch domains in GDP-associated K-Ras. The results suggest that G13A, G13D and G13I enhance the structural flexibility of the switch domains, change the correlated motion modes of the switch domains and strengthen the total motion strength of K-Ras compared with the wild-type (WT) K-Ras. Free energy landscape analyses not only show that the switch domains of the GDP-bound inactive K-Ras mainly exist as a closed state but also indicate that mutations evidently alter the free energy profile of K-Ras and affect the conformational transformation of the switch domains between the closed and open states. Analyses of hydrophobic interaction contacts and hydrogen bonding interactions show that the mutations scarcely change the interaction network of GDP with K-Ras and only disturb the interaction of GDP with the switch (SW1). In summary, two newly introduced mutations, G13A and G13I, play similar adjustment roles in the conformational transformations of two switch domains to G13D and are possibly utilized to tune the activity of K-Ras and the binding of guanine nucleotide exchange factors.
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Affiliation(s)
- Jianzhong Chen
- School of Science, Shandong Jiaotong University, Jinan, 250357, China.
| | - Lifei Wang
- School of Science, Shandong Jiaotong University, Jinan, 250357, China
| | - Wei Wang
- School of Science, Shandong Jiaotong University, Jinan, 250357, China
| | - Haibo Sun
- School of Science, Shandong Jiaotong University, Jinan, 250357, China
| | - Laixue Pang
- School of Science, Shandong Jiaotong University, Jinan, 250357, China
| | - Huayin Bao
- School of Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, 250355, China.
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49
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Khakimzhan A, Garenne D, Tickman B, Fontana J, Carothers J, Noireaux V. Complex dependence of CRISPR-Cas9 binding strength on guide RNA spacer lengths. Phys Biol 2021; 18:056003. [PMID: 34102625 DOI: 10.1088/1478-3975/ac091e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 06/08/2021] [Indexed: 12/26/2022]
Abstract
It is established that for CRISPR-Cas9 applications guide RNAs with 17-20 bp long spacer sequences are optimal for accurate target binding and cleavage. In this work we perform cell-free CRISPRa (CRISPR activation) and CRISPRi (CRISPR inhibition) experiments to demonstrate the existence of a complex dependence of CRISPR-Cas9 binding as a function of the spacer length and complementarity. Our results show that significantly truncated or mismatched spacer sequences can form stronger guide-target bonds than the conventional 17-20 bp long spacers. To explain this phenomenon, we take into consideration previous structural and single-molecule CRISPR-Cas9 experiments and develop a novel thermodynamic model of CRISPR-Cas9 target recognition.
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Affiliation(s)
- Aset Khakimzhan
- School of Physics and Astronomy, University of Minnesota, 115 Union Street SE, Minneapolis, MN 55455, United States of America
| | - David Garenne
- School of Physics and Astronomy, University of Minnesota, 115 Union Street SE, Minneapolis, MN 55455, United States of America
| | - Benjamin Tickman
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA, 98195, United States of America
| | - Jason Fontana
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA, 98195, United States of America
| | - James Carothers
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA, 98195, United States of America
- Department of Chemical Engineering, University of Washington, Seattle, WA, 98195, United States of America
- Center for Synthetic Biology, University of Washington, Seattle, WA, 98195, United States of America
| | - Vincent Noireaux
- School of Physics and Astronomy, University of Minnesota, 115 Union Street SE, Minneapolis, MN 55455, United States of America
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50
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Lee HJ, Kim HJ, Lee SJ. Mismatch Intolerance of 5'-Truncated sgRNAs in CRISPR/Cas9 Enables Efficient Microbial Single-Base Genome Editing. Int J Mol Sci 2021; 22:6457. [PMID: 34208669 PMCID: PMC8235755 DOI: 10.3390/ijms22126457] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/12/2021] [Accepted: 06/14/2021] [Indexed: 12/11/2022] Open
Abstract
The CRISPR/Cas9 system has recently emerged as a useful gene-specific editing tool. However, this approach occasionally results in the digestion of both the DNA target and similar DNA sequences due to mismatch tolerance, which remains a significant drawback of current genome editing technologies. However, our study determined that even single-base mismatches between the target DNA and 5'-truncated sgRNAs inhibited target recognition. These results suggest that a 5'-truncated sgRNA/Cas9 complex could be used to negatively select single-base-edited targets in microbial genomes. Moreover, we demonstrated that the 5'-truncated sgRNA method can be used for simple and effective single-base editing, as it enables the modification of individual bases in the DNA target, near and far from the 5' end of truncated sgRNAs. Further, 5'-truncated sgRNAs also allowed for efficient single-base editing when using an engineered Cas9 nuclease with an expanded protospacer adjacent motif (PAM; 5'-NG), which may enable whole-genome single-base editing.
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Affiliation(s)
| | | | - Sang Jun Lee
- Department of Systems Biotechnology and Institute of Microbiomics, Chung-Ang University, Anseong 17546, Korea; (H.J.L.); (H.J.K.)
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