1
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Lim D, Zhou Q, Cox KJ, Law BK, Lee M, Kokkonda P, Sreekanth V, Pergu R, Chaudhary SK, Gangopadhyay SA, Maji B, Lai S, Amako Y, Thompson DB, Subramanian HKK, Mesleh MF, Dančík V, Clemons PA, Wagner BK, Woo CM, Church GM, Choudhary A. A general approach to identify cell-permeable and synthetic anti-CRISPR small molecules. Nat Cell Biol 2022; 24:1766-1775. [PMID: 36396978 PMCID: PMC9891305 DOI: 10.1038/s41556-022-01005-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 09/02/2022] [Indexed: 11/18/2022]
Abstract
The need to control the activity and fidelity of CRISPR-associated nucleases has resulted in a demand for inhibitory anti-CRISPR molecules. The small-molecule inhibitor discovery platforms available at present are not generalizable to multiple nuclease classes, only target the initial step in the catalytic activity and require high concentrations of nuclease, resulting in inhibitors with suboptimal attributes, including poor potency. Here we report a high-throughput discovery pipeline consisting of a fluorescence resonance energy transfer-based assay that is generalizable to contemporary and emerging nucleases, operates at low nuclease concentrations and targets all catalytic steps. We applied this pipeline to identify BRD7586, a cell-permeable small-molecule inhibitor of SpCas9 that is twofold more potent than other inhibitors identified to date. Furthermore, unlike the reported inhibitors, BRD7586 enhanced SpCas9 specificity and its activity was independent of the genomic loci, DNA-repair pathway or mode of nuclease delivery. Overall, these studies describe a general pipeline to identify inhibitors of contemporary and emerging CRISPR-associated nucleases.
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Affiliation(s)
- Donghyun Lim
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- School of Biopharmaceutical and Medical Sciences, Sungshin University, Seoul, South Korea
| | - Qingxuan Zhou
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Kurt J Cox
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Benjamin K Law
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Miseon Lee
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Praveen Kokkonda
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Vedagopuram Sreekanth
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, USA
| | - Rajaiah Pergu
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Santosh K Chaudhary
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Soumyashree A Gangopadhyay
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, USA
| | - Basudeb Maji
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, USA
| | - Sophia Lai
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Yuka Amako
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - David B Thompson
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | - Hari K K Subramanian
- Department of Mechanical Engineering, University of California-Riverside, Riverside, CA, USA
| | - Michael F Mesleh
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Vlado Dančík
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Paul A Clemons
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Bridget K Wagner
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Christina M Woo
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - George M Church
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Wyss Institute for Biologically Inspired Engineering, Boston, MA, USA
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Department of Medicine, Harvard Medical School, Boston, MA, USA.
- Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, USA.
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2
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López Del Amo V, Leger BS, Cox KJ, Gill S, Bishop AL, Scanlon GD, Walker JA, Gantz VM, Choudhary A. Small-Molecule Control of Super-Mendelian Inheritance in Gene Drives. Cell Rep 2021; 31:107841. [PMID: 32610142 PMCID: PMC7587219 DOI: 10.1016/j.celrep.2020.107841] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/20/2020] [Accepted: 06/09/2020] [Indexed: 11/29/2022] Open
Abstract
Synthetic CRISPR-based gene-drive systems have tremendous potential in public health and agriculture, such as for fighting vector-borne diseases or suppressing crop pest populations. These elements can rapidly spread in a population by breaching the inheritance limit of 50% dictated by Mendel's law of gene segregation, making them a promising tool for population engineering. However, current technologies lack control over their propagation capacity, and there are important concerns about potential unchecked spreading. Here, we describe a gene-drive system in Drosophila that generates an analog inheritance output that can be tightly and conditionally controlled to between 50% and 100%. This technology uses a modified SpCas9 that responds to a synthetic, orally available small molecule, fine-tuning the inheritance probability. This system opens a new avenue to feasibility studies for spatial and temporal control of gene drives using small molecules.
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Affiliation(s)
- Víctor López Del Amo
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA 92093, USA
| | - Brittany S Leger
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Kurt J Cox
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Shubhroz Gill
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Alena L Bishop
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA 92093, USA
| | - Garrett D Scanlon
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA
| | - James A Walker
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Cancer Program, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
| | - Valentino M Gantz
- Section of Cell and Developmental Biology, University of California San Diego, La Jolla, CA 92093, USA.
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA 02115, USA.
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3
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Cox KJ, Subramanian HKK, Samaniego CC, Franco E, Choudhary A. Correction: A universal method for sensitive and cell-free detection of CRISPR-associated nucleases. Chem Sci 2020; 11:10287. [PMID: 34094293 PMCID: PMC8162274 DOI: 10.1039/d0sc90196b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
[This corrects the article DOI: 10.1039/C8SC03426E.].
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Affiliation(s)
- Kurt J Cox
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard 415 Main Street, Rm 3012 Cambridge MA 02142 USA +1 617 715 8969 +1 617 714 7445.,Department of Medicine, Harvard Medical School Boston MA 02115 USA.,Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital Boston MA 02115 USA
| | - Hari K K Subramanian
- Department of Mechanical Engineering, University of California - Riverside Riverside CA - 92521 USA +1 951 827 2442
| | - Christian Cuba Samaniego
- Department of Mechanical Engineering, University of California - Riverside Riverside CA - 92521 USA +1 951 827 2442
| | - Elisa Franco
- Department of Mechanical Engineering, University of California - Riverside Riverside CA - 92521 USA +1 951 827 2442
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard 415 Main Street, Rm 3012 Cambridge MA 02142 USA +1 617 715 8969 +1 617 714 7445.,Department of Medicine, Harvard Medical School Boston MA 02115 USA.,Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital Boston MA 02115 USA
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4
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Lim D, Sreekanth V, Cox KJ, Law BK, Wagner BK, Karp JM, Choudhary A. Engineering designer beta cells with a CRISPR-Cas9 conjugation platform. Nat Commun 2020; 11:4043. [PMID: 32792475 PMCID: PMC7426819 DOI: 10.1038/s41467-020-17725-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 07/10/2020] [Indexed: 12/23/2022] Open
Abstract
Genetically fusing protein domains to Cas9 has yielded several transformative technologies; however, the genetic modifications are limited to natural polypeptide chains at the Cas9 termini, which excludes a diverse array of molecules useful for gene editing. Here, we report chemical modifications that allow site-specific and multiple-site conjugation of a wide assortment of molecules on both the termini and internal sites of Cas9, creating a platform for endowing Cas9 with diverse functions. Using this platform, Cas9 can be modified to more precisely incorporate exogenously supplied single-stranded oligonucleotide donor (ssODN) at the DNA break site. We demonstrate that the multiple-site conjugation of ssODN to Cas9 significantly increases the efficiency of precision genome editing, and such a platform is compatible with ssODNs of diverse lengths. By leveraging the conjugation platform, we successfully engineer INS-1E, a β-cell line, to repurpose the insulin secretion machinery, which enables the glucose-dependent secretion of protective immunomodulatory factor interleukin-10. Cas9 fusions partners are often limited to natural polypeptide chains at the Cas9 termni. Here the authors present a platform for site-specific and multiple-site conjugation to both termini and internal sites of Cas9, and they apply this platform to efficiently engineer insulin-producing β cells.
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Affiliation(s)
- Donghyun Lim
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA.,Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Vedagopuram Sreekanth
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA.,Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Kurt J Cox
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA.,Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Benjamin K Law
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA.,Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Bridget K Wagner
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Jeffrey M Karp
- Engineering in Medicine, Department of Medicine, Center for Regenerative Therapeutics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.,Harvard-MIT Division of Health Sciences and Technology, MIT, Cambridge, MA, 02139, USA.,Proteomics Platform, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA.,Harvard Stem Cell Institute, Harvard University, Cambridge, MA, 02138, USA
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science Program, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA. .,Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA. .,Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA.
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5
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Manna D, Maji B, Gangopadhyay SA, Cox KJ, Zhou Q, Law BK, Mazitschek R, Choudhary A. A Singular System with Precise Dosing and Spatiotemporal Control of CRISPR‐Cas9. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201900788] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Debasish Manna
- Chemical Biology and Therapeutics Science Broad Institute of MIT and Harvard Cambridge MA 02142 USA
- Department of Medicine Harvard Medical School Boston MA 02115 USA
- Divisions of Renal Medicine and Engineering Brigham and Women's Hospital Boston MA 02115 USA
| | - Basudeb Maji
- Chemical Biology and Therapeutics Science Broad Institute of MIT and Harvard Cambridge MA 02142 USA
- Department of Medicine Harvard Medical School Boston MA 02115 USA
- Divisions of Renal Medicine and Engineering Brigham and Women's Hospital Boston MA 02115 USA
| | - Soumyashree A. Gangopadhyay
- Chemical Biology and Therapeutics Science Broad Institute of MIT and Harvard Cambridge MA 02142 USA
- Department of Medicine Harvard Medical School Boston MA 02115 USA
- Divisions of Renal Medicine and Engineering Brigham and Women's Hospital Boston MA 02115 USA
| | - Kurt J. Cox
- Chemical Biology and Therapeutics Science Broad Institute of MIT and Harvard Cambridge MA 02142 USA
| | - Qingxuan Zhou
- Chemical Biology and Therapeutics Science Broad Institute of MIT and Harvard Cambridge MA 02142 USA
| | - Benjamin K. Law
- Chemical Biology and Therapeutics Science Broad Institute of MIT and Harvard Cambridge MA 02142 USA
| | - Ralph Mazitschek
- Chemical Biology and Therapeutics Science Broad Institute of MIT and Harvard Cambridge MA 02142 USA
- Department of Medicine Harvard Medical School Boston MA 02115 USA
- Harvard T. H. Chan School of Public Health Boston MA 02115 USA
- Center for Systems Biology Massachusetts General Hospital Boston MA 02114 USA
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science Broad Institute of MIT and Harvard Cambridge MA 02142 USA
- Department of Medicine Harvard Medical School Boston MA 02115 USA
- Divisions of Renal Medicine and Engineering Brigham and Women's Hospital Boston MA 02115 USA
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6
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Manna D, Maji B, Gangopadhyay SA, Cox KJ, Zhou Q, Law BK, Mazitschek R, Choudhary A. A Singular System with Precise Dosing and Spatiotemporal Control of CRISPR-Cas9. Angew Chem Int Ed Engl 2019; 58:6285-6289. [PMID: 30834641 PMCID: PMC7067309 DOI: 10.1002/anie.201900788] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 02/24/2019] [Indexed: 12/29/2022]
Abstract
Several genome engineering applications of CRISPR-Cas9, an RNA-guided DNA endonuclease, require precision control of Cas9 activity over dosage, timing, and targeted site in an organism. While some control of Cas9 activity over dose and time have been achieved using small molecules, and spatial control using light, no singular system with control over all the three attributes exists. Furthermore, the reported small-molecule systems lack wide dynamic range, have background activity in the absence of the small-molecule controller, and are not biologically inert, while the optogenetic systems require prolonged exposure to high-intensity light. We previously reported a small-molecule-controlled Cas9 system with some dosage and temporal control. By photocaging this Cas9 activator to render it biologically inert and photoactivatable, and employing next-generation protein engineering approaches, we have built a system with a wide dynamic range, low background, and fast photoactivation using a low-intensity light while rendering the small-molecule activator biologically inert. We anticipate these precision controls will propel the development of practical applications of Cas9.
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Affiliation(s)
- Debasish Manna
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
- Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Basudeb Maji
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
- Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Soumyashree A Gangopadhyay
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
- Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Kurt J Cox
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Qingxuan Zhou
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Benjamin K Law
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
| | - Ralph Mazitschek
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
- Harvard T. H. Chan School of Public Health, Boston, MA, 02115, USA
- Center for Systems Biology, Massachusetts General Hospital, Boston, MA, 02114, USA
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
- Divisions of Renal Medicine and Engineering, Brigham and Women's Hospital, Boston, MA, 02115, USA
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7
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Cox KJ, Subramanian HKK, Samaniego CC, Franco E, Choudhary A. A universal method for sensitive and cell-free detection of CRISPR-associated nucleases. Chem Sci 2019; 10:2653-2662. [PMID: 30996981 PMCID: PMC6419926 DOI: 10.1039/c8sc03426e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 12/28/2018] [Indexed: 12/18/2022] Open
Abstract
A multitude of biological applications for CRISPR-associated (Cas) nucleases have propelled the development of robust cell-based methods for quantitation of on- and off-target activities of these nucleases. However, emerging applications of these nucleases require cell-free methods that are simple, sensitive, cost effective, high throughput, multiplexable, and generalizable to all classes of Cas nucleases. Current methods for cell-free detection are cumbersome, expensive, or require sophisticated sequencing technologies, hindering their widespread application beyond the field of life sciences. Developing such cell-free assays is challenging for multiple reasons, including that Cas nucleases are single-turnover enzymes that must be present in large excess over their substrate and that different classes of Cas nucleases exhibit wildly different operating mechanisms. Here, we report the development of a cell-free method wherein Cas nuclease activity is amplified via an in vitro transcription reaction that produces a fluorescent RNA:small-molecule adduct. We demonstrate that our method is sensitive, detecting activity from low nanomolar concentrations of several families of Cas nucleases, and can be conducted in a high-throughput microplate fashion with a simple fluorescent-based readout. We provide a mathematical framework for quantifying the activities of these nucleases and demonstrate two applications of our method, namely the development of a logic circuit and the characterization of an anti-CRISPR protein. We anticipate our method will be valuable to those studying Cas nucleases and will allow the application of Cas nuclease beyond the field of life sciences.
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Affiliation(s)
- Kurt J Cox
- Chemical Biology and Therapeutics Science , Broad Institute of MIT and Harvard , 415 Main Street, Rm 3012 , Cambridge , MA 02142 , USA . ; ; Tel: +1 617 714 7445
- Department of Medicine , Harvard Medical School , Boston , MA 02115 , USA
- Divisions of Renal Medicine and Engineering , Brigham and Women's Hospital , Boston , MA 02115 , USA
| | - Hari K K Subramanian
- Department of Mechanical Engineering , University of California - Riverside , Riverside , CA - 92521 , USA . ; Tel: +1 951 827 2442
| | - Christian Cuba Samaniego
- Department of Mechanical Engineering , University of California - Riverside , Riverside , CA - 92521 , USA . ; Tel: +1 951 827 2442
| | - Elisa Franco
- Department of Mechanical Engineering , University of California - Riverside , Riverside , CA - 92521 , USA . ; Tel: +1 951 827 2442
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science , Broad Institute of MIT and Harvard , 415 Main Street, Rm 3012 , Cambridge , MA 02142 , USA . ; ; Tel: +1 617 714 7445
- Department of Medicine , Harvard Medical School , Boston , MA 02115 , USA
- Divisions of Renal Medicine and Engineering , Brigham and Women's Hospital , Boston , MA 02115 , USA
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8
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Abstract
The CRISPR (clustered regularly interspaced short palindromic repeat)-Cas system is an adaptive immune system of bacteria that has furnished several RNA-guided DNA endonucleases (e.g., Cas9) that are revolutionizing the field of genome engineering. Cas9 is being used to effect genomic alterations as well as in gene drives, where a particular trait may be propagated through a targeted species population over several generations. The ease of targeting catalytically impaired Cas9 to any genomic loci has led to development of technologies for base editing, chromatin imaging and modeling, epigenetic editing, and gene regulation. Unsurprisingly, Cas9 is being developed for numerous applications in biotechnology and biomedical research and as a gene therapy agent for multiple pathologies. There is a need for precise control of Cas9 activity over several dimensions, including those of dose, time, and space in these applications. Such precision controls, which are required of therapeutic agents, are particularly important for Cas9 as off-target effects, chromosomal translocations, immunogenic response, genotoxicity, and embryonic mosaicism are observed at elevated levels and with prolonged activity of Cas9. Here, we provide a perspective on advances in the precision control of Cas9 over aforementioned dimensions using external stimuli (e.g., small molecules or light) for controlled activation, inhibition, or degradation of Cas9.
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Affiliation(s)
- Soumyashree A. Gangopadhyay
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
- Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, United States
- Divisions of Renal Medicine and Engineering, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
| | - Kurt J. Cox
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Debasish Manna
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
- Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, United States
- Divisions of Renal Medicine and Engineering, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
| | - Donghyun Lim
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Basudeb Maji
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
- Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, United States
- Divisions of Renal Medicine and Engineering, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
| | - Qingxuan Zhou
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
| | - Amit Choudhary
- Chemical Biology and Therapeutics Science, Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, United States
- Department of Medicine, Harvard Medical School, Boston, Massachusetts 02115, United States
- Divisions of Renal Medicine and Engineering, Brigham and Women’s Hospital, Boston, Massachusetts 02115, United States
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9
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Jester BW, Gaj A, Shomin CD, Cox KJ, Ghosh I. Testing the promiscuity of commercial kinase inhibitors against the AGC kinase group using a split-luciferase screen. J Med Chem 2012; 55:1526-37. [PMID: 22257127 DOI: 10.1021/jm201265f] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Using a newly developed competitive binding assay dependent upon the reassembly of a split reporter protein, we have tested the promiscuity of a panel of reported kinase inhibitors against the AGC group. Many non-AGC targeted kinase inhibitors target multiple members of the AGC group. In general, structurally similar inhibitors consistently exhibited activity toward the same target as well as toward closely related kinases. The inhibition data was analyzed to test the predictive value of either using identity scores derived from residues within 6 Å of the active site or identity scores derived from the entire kinase domain. The results suggest that the active site identity in certain cases may be a stronger predictor of inhibitor promiscuity. The overall results provide general guidelines for establishing inhibitor selectivity as well as for the future design of inhibitors that either target or avoid AGC kinases.
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Affiliation(s)
- Benjamin W Jester
- Department of Chemistry and Biochemistry, University of Arizona, 1306 East University Boulevard, Tucson, Arizona 85721, United States
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10
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Shomin CD, Restituyo E, Cox KJ, Ghosh I. Selection of cyclic-peptide inhibitors targeting Aurora kinase A: problems and solutions. Bioorg Med Chem 2011; 19:6743-9. [PMID: 22004849 DOI: 10.1016/j.bmc.2011.09.049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 09/21/2011] [Accepted: 09/24/2011] [Indexed: 10/17/2022]
Abstract
The critical role of Aurora kinase in cell cycle progression and its deregulation in cancer has garnered significant interest. As such, numerous Aurora targeted inhibitors have been developed to date, almost all of which target the ATP cleft at the active site. These current inhibitors display polypharmacology; that is, they target multiple kinases, and some are being actively pursued as therapeutics. Currently, there are no general approaches for targeting Aurora at sites remote from the active site, which in the long term may provide new insights regarding the inhibition of Aurora as well as other protein kinases, and provide pharmacological tools for dissecting Aurora kinase biology. Toward this long term goal, we have recently developed a bivalent selection strategy that allows for the identification of cyclic peptides that target the surface of PKA, while the active site is blocked by an ATP-competitive compound. Herein, we extend this approach to Aurora kinase (Aurora A), which required significant optimization of selection conditions to eliminate background peptides that target the streptavidin matrix upon which the kinases are immobilized. Using our optimized selection conditions, we have successfully selected several cyclic peptide ligands against Aurora A. Two of these inhibitors demonstrated IC(50) values of 10 μM and were further interrogated. The CTRPWWLC peptide was shown to display a noncompetitive mode of inhibition suggesting that alternate sites on Aurora beyond the ATP and peptide substrate binding site may be potentially targeted.
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Affiliation(s)
- Carolyn D Shomin
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
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Jester BW, Cox KJ, Gaj A, Shomin CD, Porter JR, Ghosh I. A coiled-coil enabled split-luciferase three-hybrid system: applied toward profiling inhibitors of protein kinases. J Am Chem Soc 2010; 132:11727-35. [PMID: 20669947 DOI: 10.1021/ja104491h] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The 518 protein kinases encoded in the human genome are exquisitely regulated and their aberrant function(s) are often associated with human disease. Thus, in order to advance therapeutics and to probe signal transduction cascades, there is considerable interest in the development of inhibitors that can selectively target protein kinases. However, identifying specific compounds against such a large array of protein kinases is difficult to routinely achieve utilizing traditional activity assays, where purified protein kinases are necessary. Toward a simple, rapid, and practical method for identifying specific inhibitors, we describe the development and application of a split-protein methodology utilizing a coiled-coil-assisted three-hybrid system. In this approach, a protein kinase of interest is attached to the C-terminal fragment of split-firefly luciferase and the coiled-coil Fos, which is specific for the coiled-coil Jun, is attached to the N-terminal fragment. Upon addition of Jun conjugated to a pan-kinase inhibitor such as staurosporine, a three-hybrid complex is established with concomitant reassembly of the split-luciferase enzyme. An inhibitor can be potentially identified by the commensurate loss in split-luciferase activity by displacement of the modified staurosporine. We demonstrate that this new three-hybrid approach is potentially general by testing protein kinases from the different kinase families. To interrogate whether this method allows for screening inhibitors, we tested six different protein kinases against a library of 80 known protein kinase inhibitors. Finally, we demonstrate that this three-hybrid system can potentially provide a rapid method for structure/function analysis as well as aid in the identification of allosteric inhibitors.
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Affiliation(s)
- Benjamin W Jester
- Department of Chemistry and Biochemistry, University of Arizona, 1306 East University Boulevard, Tucson, Arizona 85721, USA
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12
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Tensen CP, Cox KJ, Smit AB, van der Schors RC, Meyerhof W, Richter D, Planta RJ, Hermann PM, van Minnen J, Geraerts WP, Knol JC, Burke JF, Vreugdenhil E, van Heerikhuizen H. The lymnaea cardioexcitatory peptide (LyCEP) receptor: a G-protein-coupled receptor for a novel member of the RFamide neuropeptide family. J Neurosci 1998; 18:9812-21. [PMID: 9822740 PMCID: PMC6793288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
A novel G-protein-coupled receptor (GRL106) resembling neuropeptide Y and tachykinin receptors was cloned from the mollusc Lymnaea stagnalis. Application of a peptide extract from the Lymnaea brain to Xenopus oocytes expressing GRL106 activated a calcium-dependent chloride channel. Using this response as a bioassay, we purified the ligand for GRL106, Lymnaea cardioexcitatory peptide (LyCEP), an RFamide-type decapeptide (TPHWRPQGRF-NH2) displaying significant similarity to the Achatina cardioexcitatory peptide (ACEP-1) as well as to the recently identified family of mammalian prolactin-releasing peptides. In the Lymnaea brain, the cells that produce egg-laying hormone are the predominant site of GRL106 gene expression and appear to be innervated by LyCEP-containing fibers. Indeed, LyCEP application transiently hyperpolarizes isolated egg-laying hormone cells. In the Lymnaea pericardium, LyCEP-containing fibers end blindly at the pericardial lumen, and the heart is stimulated by LyCEP in vitro. These data confirm that LyCEP is an RFamide ligand for GRL106.
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Affiliation(s)
- C P Tensen
- Department of Biochemistry and Molecular Biology, Research Institute Neurosciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands
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13
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Tensen CP, Cox KJ, Burke JF, Leurs R, van der Schors RC, Geraerts WP, Vreugdenhil E, Heerikhuizen H. Molecular cloning and characterization of an invertebrate homologue of a neuropeptide Y receptor. Eur J Neurosci 1998; 10:3409-16. [PMID: 9824454 DOI: 10.1046/j.1460-9568.1998.00350.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neuropeptide Y is an abundant and physiologically important peptide in vertebrates having effects on food intake, sexual behaviour, blood pressure and circadian rhythms. Neuropeptide Y homologues have been found in invertebrates, where they are very likely to play similar, important roles. Although five neuropeptide Y-receptor subtypes have been identified in mammals, none has been reported from invertebrates. Here we describe the cloning of a neuropeptide Y-receptor from the brain of the snail Lymnaea stagnalis. The identity of the receptor was deduced by expressing the neuropeptide Y-receptor-encoding cDNA in Chinese Hamster Ovary cells, which were subsequently challenged with size-fractionated Lymnaea brain extracts. An active peptide, selected on the basis of its ability to induce changes in cAMP levels, was purified to homogeneity, analysed by mass spectrometry and amino acid sequence determination, and turned out to be a Lymnaea homologue of neuropeptide Y.
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Affiliation(s)
- C P Tensen
- Department of Biochemistry and Molecular Biology, Graduate School of Neurosciences, Research Institute Neurosciences, Amsterdam, The Netherlands
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14
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Abstract
Vertebrate behaviours are produced by activity in populations of neurons, but the techniques typically used to study activity allow only one or very few nerve cells to be monitored at a time. This limitation has prompted the development of methods of imaging activity in the nervous system. The overall goal of these methods is to image neural activity non-invasively in populations of neurons, ideally with high spatial and temporal resolution. We have moved closer to this goal by using confocal calcium imaging to monitor neural activity in the transparent larvae of zebrafish. Neurons were labelled either by backfilling from injections of the calcium indicator (Calcium Green dextran) into muscle or spinal cord of larvae or by injections into blastomeres early in development. The labelled neurons were bright enough at resting calcium levels to allow the identification of individual neurons in the live, intact fish, based upon their dendritic and axonal morphology. The neurons from the live animal could also be reconstructed in three dimensions for morphometric study. Neurons increased their fluorescence during activity produced by direct electrical stimulation and during escape behaviours elicited by an abrupt touch to the head or tail of the fish. The rise in calcium associated with a single action potential could be detected as an increase in fluorescence of at least 7-10%, but neurons typically showed much larger increases during behaviour. Calcium signals in the dendrites, soma and nucleus could be resolved, especially when using the line-scanning mode, which provides 2-ms temporal resolution. The imaging was used to study activity in populations of motoneurons and hindbrain neurons during the escape behaviour fish use to avoid predators. We found a massive activation of the motoneuron pool and a differential activation of populations of hindbrain neurons during escapes. The latter finding confirms predictions that the activity pattern of hindbrain neurons may help to determine the directionality of the escape. This approach should prove useful for studying the activity of populations of neurons throughout the nervous system in both normal and mutant lines of fish.
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Affiliation(s)
- J R Fetcho
- Department of Neurobiology and Behavior, SUNY at Stony Brook, NY 11794-5230, USA
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15
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Cox KJ, Tensen CP, Van der Schors RC, Li KW, van Heerikhuizen H, Vreugdenhil E, Geraerts WP, Burke JF. Cloning, characterization, and expression of a G-protein-coupled receptor from Lymnaea stagnalis and identification of a leucokinin-like peptide, PSFHSWSamide, as its endogenous ligand. J Neurosci 1997; 17:1197-205. [PMID: 9006965 PMCID: PMC6793731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/1996] [Revised: 11/07/1996] [Accepted: 11/22/1996] [Indexed: 02/03/2023] Open
Abstract
Neuropeptides are known to be important signaling molecules in several neural systems of the pond snail Lymnaea stagnalis. Although the functions of these peptides have been studied in many neurons, the nature of the postsynaptic signal transduction is mainly unknown. The cloning and characterization of neuropeptide receptors in Lymnaea thus would be very valuable in further elucidating peptidergic pathways. Indirect evidence suggests that these neuropeptides operate via G-protein-coupled mechanisms indicating the presence of G-protein-coupled receptors as the initial postsynaptic targets. Here we describe the cloning of a neuropeptide receptor from Lymnaea and the isolation of an endogenous ligand. This peptide, PSFHSWSamide, belongs to the leucokinin family of peptides, and, thus, this Lymnaea receptor is the first example of a leucokinin-like neuropeptide receptor, representing a new subfamily of G-protein-coupled neuropeptide receptors.
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Affiliation(s)
- K J Cox
- Sussex Centre for Neuroscience, School of Biological Sciences, University of Sussex, Brighton BN1 9QG, United Kingdom
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16
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Affiliation(s)
- J R Fetcho
- Department of Neurobiology and Behavior, State University of New York at Stony Brook 11794-5230, USA
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17
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Abstract
Injections of the calcium indicator calcium green dextran (CGD) into zebrafish embryos at the 1-4 cell stages were used to monitor the activity of neurons in larval fish. Dye was pressure injected into a single cell and the fish allowed to develop until post-hatching, when they were embedded in agar and viewed under a confocal microscope. Labeled larval cells, including identifiable neuronal classes such as Rohon-Beard cells and olfactory neurons, were clearly visible with extensive labeling of the whole fish following injections at the one cell embryonic stage, and a mosaic labeling pattern following injections at the 2 or 4 cell stages. Activity of neurons in the spinal cord, as indicated by intracellular calcium concentration changes, was observed directly by monitoring fluorescence changes of individual spinal neurons and groups of spinal neurons on a confocal microscope. Fluorescence increases of between 9 and 55% in spinal neurons were seen during escape responses produced when the fish was tapped on the tail. This technique can potentially be used to monitor the activity of any neuron or group of neurons with respect to behavior non-invasively in intact living zebrafish.
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Affiliation(s)
- K J Cox
- Department of Neurobiology and Behavior, State University of New York at Stony Brook 11794-5230, USA.
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Tensen CP, Van Kesteren ER, Planta RJ, Cox KJ, Burke JF, van Heerikhuizen H, Vreugdenhil E. A G protein-coupled receptor with low density lipoprotein-binding motifs suggests a role for lipoproteins in G-linked signal transduction. Proc Natl Acad Sci U S A 1994; 91:4816-20. [PMID: 8197140 PMCID: PMC43879 DOI: 10.1073/pnas.91.11.4816] [Citation(s) in RCA: 86] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We have isolated and analyzed a cDNA from the central nervous system of the mollusc Lymnaea stagnalis encoding a putative receptor, which might be a natural hybrid between two different classes of receptor proteins. Preceded by a signal peptide, two types of repeated sequences are present in the N-terminal part of the protein. The first repeat displays a high sequence similarity to the extracellular binding domains of the low density lipoprotein receptor, which binds and internalizes cholesterol-containing apolipoproteins. The second repeat and the C-terminal part of the Lymnaea receptor are very similar to regions of a specific class of guanine nucleotide-binding protein-coupled receptors, the mammalian glycoprotein hormone receptors. The mRNA encoding the receptor is predominantly expressed in a small number of neurons within the central nervous system and to a lesser extent in the heart.
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Affiliation(s)
- C P Tensen
- Department of Zoology, Graduate School of Neurosciences Amsterdam, Vrije Universiteit, Faculty of Biology, The Netherlands
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Abstract
Despite almost a century of research, the mechanism of anaesthesia remains obscure and there is still no agreement on the location of the site(s) of action. Because the potencies of general anaesthetics increase in proportion to their solubility in olive oil, this led to a consensus that the site is within the cell membrane. This led to theories that lipid bilayer perturbation was the primary event, which was then transmitted to a membrane protein. But at the concentrations used clinically, such perturbations are small. A plausible site would be in or on ion channels at the synapse, where a number of modulatory effects have been described. A possible location for such a site would be at the protein-lipid interface. We report here that anaesthetics inhibit protein kinase C, a key component in signal transduction. The potency is a linear function of the octanol-water partition coefficient (the Meyer-Overton rule of anaesthesia). The effect was obtained in a lipid-free assay, implicating a hydrophobic site in the protein, supporting the contention that a (membrane) protein may be a target for anaesthetic interactions. In a lipid-dependent assay, a potential role of lipids in the protein-site model was demonstrated. The inhibition was absent in the isolated catalytic domain, suggesting that the site of inhibition is on the regulatory subunit, which is unique to protein kinase C.
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Affiliation(s)
- S J Slater
- Department of Pathology and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
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Cox KJ, Thomas AS. The application of immunoblotting to the phenotyping of haptoglobin. J Forensic Sci 1992; 37:1652-5. [PMID: 1453173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
An immunoblotting method for phenotyping haptoglobin in serum and bloodstains has been developed. Haptoglobin isoproteins were separated by polyacrylamide gradient gel electrophoresis and then transferred to nitrocellulose by electroblotting. The use of 1 mm gels facilitated more rapid and effective transfer than conventional 3 mm thick gels. Nitrocellulose blots were developed by double antibody enzyme immunoassay. The detection limit for serum and bloodstains was improved 16 times compared to conventional staining using O-tolidine. The method could detect haptoglobin phenotypes from 0.001 microliter of whole blood. This detection limit is approximately 8 times lower than that of group specific-component analysis by immunoblotting.
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Affiliation(s)
- K J Cox
- Forensic Biology section, Queensland Department of Health, Brisbane, Australia
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Abstract
The transition of gramicidin from a nonchannel to a channel form was investigated using mixed-chain phosphatidylcholine lipid bilayers. Gramicidin and phospholipids were codispersed, after removal of the solvents chloroform/methanol or trifluoroethanol which resulted in nonchannel and channel conformations, respectively, as confirmed using circular dichroism (CD). The fluorescence emission maxima of the nonchannel form were shifted toward shorter wavelengths by heating at 60 degrees C (for 0-12 h), which converted it to a channel form, again as confirmed by CD. The channel form did not respond to heat treatment. Heat treatment also increased the fluorescence anisotropy of the nonchannel gramicidin tryptophans. The rate of transition from the nonchannel to channel conformation was found to be faster if phosphatidylethanolamine was present in combination with phosphatidylcholine compared to phosphatidylcholine alone. Also, gramicidin in bilayers of the polyunsaturated 1-palmitoyl-2-docosahexaenoyl-phosphatidylcholine converted more rapidly compared to 1-palmitoyl-2-oleoylphosphatidylcholine. Using the fluorescence anisotropy of the membrane lipid probe 1,6-diphenyl-1,3,5-hexatriene, it was also shown that the motional properties of the surrounding lipid acyl chains differed for the channel and nonchannel gramicidin conformations. The possibility that lipids tending to favor the hexagonal phase (HII) would enhance the rate of the nonchannel to channel transition was supported by 31P NMR which revealed the presence of some HII lipids in the channel preparations. The results of this study suggest that gramicidin may serve as a useful model for similar conformational transitions in other more complex membrane proteins.
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Affiliation(s)
- K J Cox
- Department of Pathology and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
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Fairnie IJ, Cox KJ. Death in lambs after emasculation and tail docking. Aust Vet J 1969; 45:39. [PMID: 5812803 DOI: 10.1111/j.1751-0813.1969.tb01879.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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