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Jung J, Kim S, Rah SH, Lee J, Shon MJ. Force-fluorescence setup for observing protein-DNA interactions under load. Methods Enzymol 2024; 694:137-165. [PMID: 38492949 DOI: 10.1016/bs.mie.2024.01.003] [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] [Indexed: 03/18/2024]
Abstract
This chapter explores advanced single-molecule techniques for studying protein-DNA interactions, particularly focusing on Replication Protein A (RPA) using a force-fluorescence setup. It combines magnetic tweezers (MT) with total internal reflection fluorescence (TIRF) microscopy, enabling detailed observation of DNA behavior under mechanical stress. The chapter details the use of DNA hairpins and bare DNA to examine RPA's binding dynamics and its influence on DNA's mechanical properties. This approach provides deeper insights into RPA's role in DNA replication, repair, and recombination, highlighting its significance in maintaining genomic stability.
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Affiliation(s)
- Jaehun Jung
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Subin Kim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea
| | - Sang-Hyun Rah
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Jayil Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), Ulsan, Republic of Korea; Institute of Basic Science Center for Genomic Integrity, Ulsan, Republic of Korea
| | - Min Ju Shon
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea.
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2
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Hong S, Yang T, Go A, Kim H, Yoon TY, Shon MJ. High-speed measurements of SNARE-complexin interactions using magnetic tweezers. Methods Enzymol 2024; 694:109-135. [PMID: 38492948 DOI: 10.1016/bs.mie.2024.01.002] [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] [Indexed: 03/18/2024]
Abstract
In neuroscience, understanding the mechanics of synapses, especially the function of force-sensitive proteins at the molecular level, is essential. This need emphasizes the importance of precise measurement of synaptic protein interactions. Addressing this, we introduce high-resolution magnetic tweezers (MT) as a novel method to probe the mechanics of synapse-related proteins with high precision. We demonstrate this technique through studying SNARE-complexin interactions, crucial for synaptic transmission, showcasing its capability to apply specific forces to individual molecules. Our results reveal that high-resolution MT provides in-depth insights into the stability and dynamic transitions of synaptic protein complexes. This method is a significant advancement in synapse biology, offering a new tool for researchers to investigate the impact of mechanical forces on synaptic functions and their implications for neurological disorders.
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Affiliation(s)
- Seokyun Hong
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Taehyun Yang
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea
| | - Ara Go
- Engitein Research Institute, Engitein, Siheung, Republic of Korea
| | - Haesoo Kim
- Engitein Research Institute, Engitein, Siheung, Republic of Korea
| | - Tae-Young Yoon
- School of Biological Sciences and Institute for Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea; Department of Biomarker Discovery, PROTEINA Co., Ltd, Seoul, Republic of Korea.
| | - Min Ju Shon
- Department of Physics, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, Republic of Korea.
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3
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Hao T, Feng N, Gong F, Yu Y, Liu J, Ren YX. Complexin-1 regulated assembly of single neuronal SNARE complex revealed by single-molecule optical tweezers. Commun Biol 2023; 6:155. [PMID: 36750663 PMCID: PMC9905088 DOI: 10.1038/s42003-023-04506-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 01/19/2023] [Indexed: 02/09/2023] Open
Abstract
The dynamic assembly of the Synaptic-soluble N-ethylmaleimide-sensitive factor Attachment REceptor (SNARE) complex is crucial to understand membrane fusion. Traditional ensemble study meets the challenge to dissect the dynamic assembly of the protein complex. Here, we apply minute force on a tethered protein complex through dual-trap optical tweezers and study the folding dynamics of SNARE complex under mechanical force regulated by complexin-1 (CpxI). We reconstruct the clamp and facilitate functions of CpxI in vitro and identify different interplay mechanism of CpxI fragment binding on the SNARE complex. Specially, while the N-terminal domain (NTD) plays a dominant role of the facilitate function, CTD is mainly related to clamping. And the mixture of 1-83aa and CTD of CpxI can efficiently reconstitute the inhibitory signal identical to that the full-length CpxI functions. Our observation identifies the important chaperone role of the CpxI molecule in the dynamic assembly of SNARE complex under mechanical tension, and elucidates the specific function of each fragment of CpxI molecules in the chaperone process.
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Affiliation(s)
- Tongrui Hao
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Science, Shanghai, 200031, China. .,University of Chinese Academy of Sciences, Beijing, 200049, China.
| | - Nan Feng
- grid.9227.e0000000119573309State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Science, Shanghai, 200031 China ,grid.410726.60000 0004 1797 8419University of Chinese Academy of Sciences, Beijing, 200049 China
| | - Fan Gong
- grid.9227.e0000000119573309National Facility for Protein Science in Shanghai, Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210 China
| | - Yang Yu
- grid.9227.e0000000119573309National Facility for Protein Science in Shanghai, Zhangjiang Lab, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210 China
| | - Jiaquan Liu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Science, Shanghai, 200031, China.
| | - Yu-Xuan Ren
- Institute for Translational Brain Research, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
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4
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Zhang Y, Ma L, Bao H. Energetics, kinetics, and pathways of SNARE assembly in membrane fusion. Crit Rev Biochem Mol Biol 2022; 57:443-460. [PMID: 36151854 PMCID: PMC9588726 DOI: 10.1080/10409238.2022.2121804] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Fusion of transmitter-containing vesicles with plasma membranes at the synaptic and neuromuscular junctions mediates neurotransmission and muscle contractions, respectively, thereby underlying all thoughts and actions. The fusion process is driven by the coupled folding and assembly of three synaptic SNARE proteins--syntaxin-1 and SNAP-25 on the target plasma membrane (t-SNAREs) and VAMP2 on the vesicular membrane (v-SNARE) into a four-helix bundle. Their assembly is chaperoned by Munc18-1 and many other proteins to achieve the speed and accuracy required for neurotransmission. However, the physiological pathway of SNARE assembly and its coupling to membrane fusion remains unclear. Here, we review recent progress in understanding SNARE assembly and membrane fusion, with a focus on results obtained by single-molecule manipulation approaches and electric recordings of single fusion pores. We describe two pathways of synaptic SNARE assembly, their associated intermediates, energetics, and kinetics. Assembly of the three SNAREs in vitro begins with the formation of a t-SNARE binary complex, on which VAMP2 folds in a stepwise zipper-like fashion. Munc18-1 significantly alters the SNARE assembly pathway: syntaxin-1 and VAMP2 first bind on the surface of Munc18-1 to form a template complex, with which SNAP-25 associates to conclude SNARE assembly and displace Munc18-1. During membrane fusion, multiple trans-SNARE complexes cooperate to open a dynamic fusion pore in a manner dependent upon their copy number and zippering states. Together, these results demonstrate that stepwise and cooperative SNARE assembly drive stagewise membrane fusion.
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Affiliation(s)
- Yongli Zhang
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA;,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA;,Conatct: and
| | - Lu Ma
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA;,Present address: Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Huan Bao
- Department of Molecular Medicine, The Scripps Research Institute, 130 Scripps Way, Jupiter, Florida, 33458,Conatct: and
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5
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Abstract
Single-molecule magnetic tweezers deliver magnetic force and torque to single target molecules, permitting the study of dynamic changes in biomolecular structures and their interactions. Because the magnetic tweezer setups can generate magnetic fields that vary slowly over tens of millimeters-far larger than the nanometer scale of the single molecule events being observed-this technique can maintain essentially constant force levels during biochemical experiments while generating a biologically meaningful force on the order of 1-100 pN. When using bead-tether constructs to pull on single molecules, smaller magnetic beads and shorter submicrometer tethers improve dynamic response times and measurement precision. In addition, employing high-speed cameras, stronger light sources, and a graphics programming unit permits true high-resolution single-molecule magnetic tweezers that can track nanometer changes in target molecules on a millisecond or even submillisecond time scale. The unique force-clamping capacity of the magnetic tweezer technique provides a way to conduct measurements under near-equilibrium conditions and directly map the energy landscapes underlying various molecular phenomena. High-resolution single-molecule magnetic tweezers can thus be used to monitor crucial conformational changes in single-protein molecules, including those involved in mechanotransduction and protein folding. Expected final online publication date for the Annual Review of Biochemistry, Volume 91 is June 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Hyun-Kyu Choi
- Wallace H. Coulter Department of Biomedical Engineering and Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Hyun Gyu Kim
- School of Biological Sciences and Institute for Molecular Biology and Genetics, Seoul National University, Seoul, South Korea;
| | - Min Ju Shon
- Department of Physics and School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science & Technology (POSTECH), Pohang, South Korea;
| | - Tae-Young Yoon
- School of Biological Sciences and Institute for Molecular Biology and Genetics, Seoul National University, Seoul, South Korea;
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6
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Yang T, Park C, Rah SH, Shon MJ. Nano-Precision Tweezers for Mechanosensitive Proteins and Beyond. Mol Cells 2022; 45:16-25. [PMID: 35114644 PMCID: PMC8819490 DOI: 10.14348/molcells.2022.2026] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 01/10/2022] [Accepted: 01/12/2022] [Indexed: 11/27/2022] Open
Abstract
Mechanical forces play pivotal roles in regulating cell shape, function, and fate. Key players that govern the mechanobiological interplay are the mechanosensitive proteins found on cell membranes and in cytoskeleton. Their unique nanomechanics can be interrogated using single-molecule tweezers, which can apply controlled forces to the proteins and simultaneously measure the ensuing structural changes. Breakthroughs in high-resolution tweezers have enabled the routine monitoring of nanometer-scale, millisecond dynamics as a function of force. Undoubtedly, the advancement of structural biology will be further fueled by integrating static atomic-resolution structures and their dynamic changes and interactions observed with the force application techniques. In this minireview, we will introduce the general principles of single-molecule tweezers and their recent applications to the studies of force-bearing proteins, including the synaptic proteins that need to be categorized as mechanosensitive in a broad sense. We anticipate that the impact of nano-precision approaches in mechanobiology research will continue to grow in the future.
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Affiliation(s)
- Taehyun Yang
- Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea
| | - Celine Park
- Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea
| | - Sang-Hyun Rah
- Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea
| | - Min Ju Shon
- Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang 37673, Korea
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7
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Extreme parsimony in ATP consumption by 20S complexes in the global disassembly of single SNARE complexes. Nat Commun 2021; 12:3206. [PMID: 34050166 PMCID: PMC8163800 DOI: 10.1038/s41467-021-23530-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 04/30/2021] [Indexed: 11/08/2022] Open
Abstract
Fueled by ATP hydrolysis in N-ethylmaleimide sensitive factor (NSF), the 20S complex disassembles rigid SNARE (soluble NSF attachment protein receptor) complexes in single unraveling step. This global disassembly distinguishes NSF from other molecular motors that make incremental and processive motions, but the molecular underpinnings of its remarkable energy efficiency remain largely unknown. Using multiple single-molecule methods, we found remarkable cooperativity in mechanical connection between NSF and the SNARE complex, which prevents dysfunctional 20S complexes that consume ATP without productive disassembly. We also constructed ATP hydrolysis cycle of the 20S complex, in which NSF largely shows randomness in ATP binding but switches to perfect ATP hydrolysis synchronization to induce global SNARE disassembly, minimizing ATP hydrolysis by non-20S complex-forming NSF molecules. These two mechanisms work in concert to concentrate ATP consumption into functional 20S complexes, suggesting evolutionary adaptations by the 20S complex to the energetically expensive mechanical task of SNARE complex disassembly. Fueled by ATP hydrolysis in N-ethylmaleimide sensitive factor (NSF), the 20S complex disassembles SNARE complexes in a single unravelling step. Here authors use single-molecule methods to show cooperativity between the NSF and SNARE complex, which prevents ATP consumption without productive disassembly.
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8
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Complexin Suppresses Spontaneous Exocytosis by Capturing the Membrane-Proximal Regions of VAMP2 and SNAP25. Cell Rep 2021; 32:107926. [PMID: 32698012 PMCID: PMC7116205 DOI: 10.1016/j.celrep.2020.107926] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 02/28/2020] [Accepted: 06/26/2020] [Indexed: 01/29/2023] Open
Abstract
The neuronal protein complexin contains multiple domains that exert clamping and facilitatory functions to tune spontaneous and action potential-triggered synaptic release. We address the clamping mechanism and show that the accessory helix of complexin arrests assembly of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex that forms the core machinery of intracellular membrane fusion. In a reconstituted fusion assay, site-and stage-specific photo-cross-linking reveals that, prior to fusion, the complexin accessory helix laterally binds the membrane-proximal C-terminal ends of SNAP25 and VAMP2. Corresponding complexin interface mutants selectively increase spontaneous release of neuro-transmitters in living neurons, implying that the accessory helix suppresses final zippering/assembly of the SNARE four-helix bundle by restraining VAMP2 and SNAP25.
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9
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Abstract
SNARE proteins and Sec1/Munc18 (SM) proteins constitute the core molecular engine that drives nearly all intracellular membrane fusion and exocytosis. While SNAREs are known to couple their folding and assembly to membrane fusion, the physiological pathways of SNARE assembly and the mechanistic roles of SM proteins have long been enigmatic. Here, we review recent advances in understanding the SNARE-SM fusion machinery with an emphasis on biochemical and biophysical studies of proteins that mediate synaptic vesicle fusion. We begin by discussing the energetics, pathways, and kinetics of SNARE folding and assembly in vitro. Then, we describe diverse interactions between SM and SNARE proteins and their potential impact on SNARE assembly in vivo. Recent work provides strong support for the idea that SM proteins function as chaperones, their essential role being to enable fast, accurate SNARE assembly. Finally, we review the evidence that SM proteins collaborate with other SNARE chaperones, especially Munc13-1, and briefly discuss some roles of SNARE and SM protein deficiencies in human disease.
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Affiliation(s)
- Yongli Zhang
- Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06520, USA;
| | - Frederick M Hughson
- Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA;
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10
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Choi HK, Min D, Kang H, Shon MJ, Rah SH, Kim HC, Jeong H, Choi HJ, Bowie JU, Yoon TY. Watching helical membrane proteins fold reveals a common N-to-C-terminal folding pathway. Science 2020; 366:1150-1156. [PMID: 31780561 DOI: 10.1126/science.aaw8208] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 08/30/2019] [Accepted: 11/05/2019] [Indexed: 02/03/2023]
Abstract
To understand membrane protein biogenesis, we need to explore folding within a bilayer context. Here, we describe a single-molecule force microscopy technique that monitors the folding of helical membrane proteins in vesicle and bicelle environments. After completely unfolding the protein at high force, we lower the force to initiate folding while transmembrane helices are aligned in a zigzag manner within the bilayer, thereby imposing minimal constraints on folding. We used the approach to characterize the folding pathways of the Escherichia coli rhomboid protease GlpG and the human β2-adrenergic receptor. Despite their evolutionary distance, both proteins fold in a strict N-to-C-terminal fashion, accruing structures in units of helical hairpins. These common features suggest that integral helical membrane proteins have evolved to maximize their fitness with cotranslational folding.
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Affiliation(s)
- Hyun-Kyu Choi
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea.,School of Biological Sciences, Seoul National University, Seoul 08826, South Korea.,Institute for Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
| | - Duyoung Min
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, CA 90095, USA.,Department of Chemistry, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea
| | - Hyunook Kang
- School of Biological Sciences, Seoul National University, Seoul 08826, South Korea
| | - Min Ju Shon
- School of Biological Sciences, Seoul National University, Seoul 08826, South Korea.,Institute for Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
| | - Sang-Hyun Rah
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea.,School of Biological Sciences, Seoul National University, Seoul 08826, South Korea.,Institute for Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
| | - Hak Chan Kim
- School of Biological Sciences, Seoul National University, Seoul 08826, South Korea
| | - Hawoong Jeong
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| | - Hee-Jung Choi
- School of Biological Sciences, Seoul National University, Seoul 08826, South Korea.
| | - James U Bowie
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, CA 90095, USA.
| | - Tae-Young Yoon
- School of Biological Sciences, Seoul National University, Seoul 08826, South Korea. .,Institute for Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
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11
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Munc13-1 MUN domain and Munc18-1 cooperatively chaperone SNARE assembly through a tetrameric complex. Proc Natl Acad Sci U S A 2019; 117:1036-1041. [PMID: 31888993 DOI: 10.1073/pnas.1914361117] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Munc13-1 is a large multifunctional protein essential for synaptic vesicle fusion and neurotransmitter release. Its dysfunction has been linked to many neurological disorders. Evidence suggests that the MUN domain of Munc13-1 collaborates with Munc18-1 to initiate SNARE assembly, thereby priming vesicles for fast calcium-triggered vesicle fusion. The underlying molecular mechanism, however, is poorly understood. Recently, it was found that Munc18-1 catalyzes neuronal SNARE assembly through an obligate template complex intermediate containing Munc18-1 and 2 SNARE proteins-syntaxin 1 and VAMP2. Here, using single-molecule force spectroscopy, we discovered that the MUN domain of Munc13-1 stabilizes the template complex by ∼2.1 kBT. The MUN-bound template complex enhances SNAP-25 binding to the templated SNAREs and subsequent full SNARE assembly. Mutational studies suggest that the MUN-bound template complex is functionally important for SNARE assembly and neurotransmitter release. Taken together, our observations provide a potential molecular mechanism by which Munc13-1 and Munc18-1 cooperatively chaperone SNARE folding and assembly, thereby regulating synaptic vesicle fusion.
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12
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Shon MJ, Rah SH, Yoon TY. Submicrometer elasticity of double-stranded DNA revealed by precision force-extension measurements with magnetic tweezers. SCIENCE ADVANCES 2019; 5:eaav1697. [PMID: 31206015 PMCID: PMC6561745 DOI: 10.1126/sciadv.aav1697] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 05/03/2019] [Indexed: 05/07/2023]
Abstract
Submicrometer elasticity of double-stranded DNA (dsDNA) governs nanoscale bending of DNA segments and their interactions with proteins. Single-molecule force spectroscopy, including magnetic tweezers (MTs), is an important tool for studying DNA mechanics. However, its application to short DNAs under 1 μm is limited. We developed an MT-based method for precise force-extension measurements in the 100-nm regime that enables in situ correction of the error in DNA extension measurement, and normalizes the force variability across beads by exploiting DNA hairpins. The method reduces the lower limit of tractable dsDNA length down to 198 base pairs (bp) (67 nm), an order-of-magnitude improvement compared to conventional tweezing experiments. Applying this method and the finite worm-like chain model we observed an essentially constant persistence length across the chain lengths studied (198 bp to 10 kbp), which steeply depended on GC content and methylation. This finding suggests a potential sequence-dependent mechanism for short-DNA elasticity.
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Affiliation(s)
- Min Ju Shon
- School of Biological Sciences and Institute for Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
- Corresponding author. (T.-Y.Y.); (M.J.S.)
| | - Sang-Hyun Rah
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
| | - Tae-Young Yoon
- School of Biological Sciences and Institute for Molecular Biology and Genetics, Seoul National University, Seoul 08826, South Korea
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, South Korea
- Corresponding author. (T.-Y.Y.); (M.J.S.)
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