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van Boven MA, Mestroni M, Zwijnenburg PJG, Verhage M, Cornelisse LN. A de novo missense mutation in synaptotagmin-1 associated with neurodevelopmental disorder desynchronizes neurotransmitter release. Mol Psychiatry 2024:10.1038/s41380-024-02444-5. [PMID: 38321119 DOI: 10.1038/s41380-024-02444-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/12/2024] [Accepted: 01/22/2024] [Indexed: 02/08/2024]
Abstract
Synaptotagmin-1 (Syt1) is a presynaptic calcium sensor with two calcium binding domains, C2A and C2B, that triggers action potential-induced synchronous neurotransmitter release, while suppressing asynchronous and spontaneous release. We identified a de novo missense mutation (P401L) in the C2B domain in a patient with developmental delay and autistic symptoms. Expressing the orthologous mouse mutant (P400L) in cultured Syt1 null mutant neurons revealed a reduction in dendrite outgrowth with a proportional reduction in synapses. This was not observed in single Syt1PL-rescued neurons that received normal synaptic input when cultured in a control network. Patch-clamp recordings showed that spontaneous miniature release events per synapse were increased more than 500% in Syt1PL-rescued neurons, even beyond the increased rates in Syt1 KO neurons. Furthermore, action potential-induced asynchronous release was increased more than 100%, while synchronous release was unaffected. A similar shift to more asynchronous release was observed during train stimulations. These cellular phenotypes were also observed when Syt1PL was overexpressed in wild type neurons. Our findings show that Syt1PL desynchronizes neurotransmission by increasing the readily releasable pool for asynchronous release and reducing the suppression of spontaneous and asynchronous release. Neurons respond to this by shortening their dendrites, possibly to counteract the increased synaptic input. Syt1PL acts in a dominant-negative manner supporting a causative role for the mutation in the heterozygous patient. We propose that the substitution of a rigid proline to a more flexible leucine at the bottom of the C2B domain impairs clamping of release by interfering with Syt1's primary interface with the SNARE complex. This is a novel cellular phenotype, distinct from what was previously found for other SYT1 disease variants, and points to a role for spontaneous and asynchronous release in SYT1-associated neurodevelopmental disorder.
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Affiliation(s)
- Maaike A van Boven
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Vrije Universiteit (VU) Amsterdam, 1081 HV, Amsterdam, The Netherlands
| | - Marta Mestroni
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Vrije Universiteit (VU) Amsterdam, 1081 HV, Amsterdam, The Netherlands
| | | | - Matthijs Verhage
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Vrije Universiteit (VU) Amsterdam, 1081 HV, Amsterdam, The Netherlands
- Department of Functional Genomics and Department of Human Genetics, Center for Neurogenomics and Cognitive Research (CNCR), Amsterdam UMC-Location VUmc, 1081 HV, Amsterdam, The Netherlands
| | - L Niels Cornelisse
- Department of Functional Genomics and Department of Human Genetics, Center for Neurogenomics and Cognitive Research (CNCR), Amsterdam UMC-Location VUmc, 1081 HV, Amsterdam, The Netherlands.
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Mendez D, Holton JM, Lyubimov AY, Hollatz S, Mathews II, Cichosz A, Martirosyan V, Zeng T, Stofer R, Liu R, Song J, McPhillips S, Soltis M, Cohen AE. Deep residual networks for crystallography trained on synthetic data. Acta Crystallogr D Struct Biol 2024; 80:26-43. [PMID: 38164955 PMCID: PMC10833344 DOI: 10.1107/s2059798323010586] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2023] [Accepted: 12/12/2023] [Indexed: 01/03/2024] Open
Abstract
The use of artificial intelligence to process diffraction images is challenged by the need to assemble large and precisely designed training data sets. To address this, a codebase called Resonet was developed for synthesizing diffraction data and training residual neural networks on these data. Here, two per-pattern capabilities of Resonet are demonstrated: (i) interpretation of crystal resolution and (ii) identification of overlapping lattices. Resonet was tested across a compilation of diffraction images from synchrotron experiments and X-ray free-electron laser experiments. Crucially, these models readily execute on graphics processing units and can thus significantly outperform conventional algorithms. While Resonet is currently utilized to provide real-time feedback for macromolecular crystallography users at the Stanford Synchrotron Radiation Lightsource, its simple Python-based interface makes it easy to embed in other processing frameworks. This work highlights the utility of physics-based simulation for training deep neural networks and lays the groundwork for the development of additional models to enhance diffraction collection and analysis.
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Affiliation(s)
- Derek Mendez
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - James M. Holton
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Biochemistry and Biophysics, UC San Francisco, San Francisco, CA 94158, USA
| | - Artem Y. Lyubimov
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Sabine Hollatz
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Irimpan I. Mathews
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Aleksander Cichosz
- Department of Statistics and Applied Probability, UC Santa Barbara, Santa Barbara, CA 93106, USA
| | - Vardan Martirosyan
- Department of Mathematics, UC Santa Barbara, Santa Barbara, CA 93106, USA
| | - Teo Zeng
- Department of Statistics and Applied Probability, UC Santa Barbara, Santa Barbara, CA 93106, USA
| | - Ryan Stofer
- Department of Statistics and Applied Probability, UC Santa Barbara, Santa Barbara, CA 93106, USA
| | - Ruobin Liu
- Department of Statistics and Applied Probability, UC Santa Barbara, Santa Barbara, CA 93106, USA
| | - Jinhu Song
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Scott McPhillips
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Mike Soltis
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Aina E. Cohen
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
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Ganapati V, Tchoń D, Brewster AS, Sauter NK. Self-Supervised Deep Learning for Model Correction in the Computational Crystallography Toolbox. ArXiv 2023:arXiv:2307.01901v1. [PMID: 37461412 PMCID: PMC10350105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 07/23/2023]
Abstract
The Computational Crystallography Toolbox (cctbx) is open-source software that allows for processing of crystallographic data, including from serial femtosecond crystallography (SFX), for macromolecular structure determination. We aim to use the modules in cctbx to determine the oxidation state of individual metal atoms in a macromolecule. Changes in oxidation state are reflected in small shifts of the atom's X-ray absorption edge. These energy shifts can be extracted from the diffraction images recorded in serial femtosecond crystallography, given knowledge of a forward physics model. However, as the diffraction changes only slightly due to the absorption edge shift, inaccuracies in the forward physics model make it extremely challenging to observe the oxidation state. In this work, we describe the potential impact of using self-supervised deep learning to correct the scientific model in cctbx and provide uncertainty quantification. We provide code for forward model simulation and data analysis, built from cctbx modules, at https://github.com/gigantocypris/SPREAD, which can be integrated with machine learning. We describe open questions in algorithm development to help spur advances through dialog between crystallographers and machine learning researchers. New methods could help elucidate charge transfer processes in many reactions, including key events in photosynthesis.
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Affiliation(s)
- Vidya Ganapati
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Engineering, Swarthmore College, Swarthmore, PA 19081, USA
| | - Daniel Tchoń
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Aaron S. Brewster
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Nicholas K. Sauter
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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Cui L, Li H, Xi Y, Hu Q, Liu H, Fan J, Xiang Y, Zhang X, Shui W, Lai Y. Vesicle trafficking and vesicle fusion: mechanisms, biological functions, and their implications for potential disease therapy. Mol Biomed 2022; 3:29. [PMID: 36129576 PMCID: PMC9492833 DOI: 10.1186/s43556-022-00090-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/12/2022] [Indexed: 11/10/2022] Open
Abstract
Intracellular vesicle trafficking is the fundamental process to maintain the homeostasis of membrane-enclosed organelles in eukaryotic cells. These organelles transport cargo from the donor membrane to the target membrane through the cargo containing vesicles. Vesicle trafficking pathway includes vesicle formation from the donor membrane, vesicle transport, and vesicle fusion with the target membrane. Coat protein mediated vesicle formation is a delicate membrane budding process for cargo molecules selection and package into vesicle carriers. Vesicle transport is a dynamic and specific process for the cargo containing vesicles translocation from the donor membrane to the target membrane. This process requires a group of conserved proteins such as Rab GTPases, motor adaptors, and motor proteins to ensure vesicle transport along cytoskeletal track. Soluble N-ethyl-maleimide-sensitive factor (NSF) attachment protein receptors (SNARE)-mediated vesicle fusion is the final process for vesicle unloading the cargo molecules at the target membrane. To ensure vesicle fusion occurring at a defined position and time pattern in eukaryotic cell, multiple fusogenic proteins, such as synaptotagmin (Syt), complexin (Cpx), Munc13, Munc18 and other tethering factors, cooperate together to precisely regulate the process of vesicle fusion. Dysfunctions of the fusogenic proteins in SNARE-mediated vesicle fusion are closely related to many diseases. Recent studies have suggested that stimulated membrane fusion can be manipulated pharmacologically via disruption the interface between the SNARE complex and Ca2+ sensor protein. Here, we summarize recent insights into the molecular mechanisms of vesicle trafficking, and implications for the development of new therapeutics based on the manipulation of vesicle fusion.
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Moreno-Chicano T, Carey LM, Axford D, Beale JH, Doak RB, Duyvesteyn HME, Ebrahim A, Henning RW, Monteiro DCF, Myles DA, Owada S, Sherrell DA, Straw ML, Šrajer V, Sugimoto H, Tono K, Tosha T, Tews I, Trebbin M, Strange RW, Weiss KL, Worrall JAR, Meilleur F, Owen RL, Ghiladi RA, Hough MA. Complementarity of neutron, XFEL and synchrotron crystallography for defining the structures of metalloenzymes at room temperature. IUCrJ 2022; 9:610-624. [PMID: 36071813 PMCID: PMC9438502 DOI: 10.1107/s2052252522006418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 06/21/2022] [Indexed: 06/15/2023]
Abstract
Room-temperature macromolecular crystallography allows protein structures to be determined under close-to-physiological conditions, permits dynamic freedom in protein motions and enables time-resolved studies. In the case of metalloenzymes that are highly sensitive to radiation damage, such room-temperature experiments can present challenges, including increased rates of X-ray reduction of metal centres and site-specific radiation-damage artefacts, as well as in devising appropriate sample-delivery and data-collection methods. It can also be problematic to compare structures measured using different crystal sizes and light sources. In this study, structures of a multifunctional globin, dehaloperoxidase B (DHP-B), obtained using several methods of room-temperature crystallographic structure determination are described and compared. Here, data were measured from large single crystals and multiple microcrystals using neutrons, X-ray free-electron laser pulses, monochromatic synchrotron radiation and polychromatic (Laue) radiation light sources. These approaches span a range of 18 orders of magnitude in measurement time per diffraction pattern and four orders of magnitude in crystal volume. The first room-temperature neutron structures of DHP-B are also presented, allowing the explicit identification of the hydrogen positions. The neutron data proved to be complementary to the serial femtosecond crystallography data, with both methods providing structures free of the effects of X-ray radiation damage when compared with standard cryo-crystallography. Comparison of these room-temperature methods demonstrated the large differences in sample requirements, data-collection time and the potential for radiation damage between them. With regard to the structure and function of DHP-B, despite the results being partly limited by differences in the underlying structures, new information was gained on the protonation states of active-site residues which may guide future studies of DHP-B.
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Affiliation(s)
- Tadeo Moreno-Chicano
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Leiah M. Carey
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA
| | - Danny Axford
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, United Kingdom
| | - John H. Beale
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, United Kingdom
| | - R. Bruce Doak
- Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Helen M. E. Duyvesteyn
- Division of Structural Biology (STRUBI), University of Oxford, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Oxford OX3 7BN, United Kingdom
| | - Ali Ebrahim
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, United Kingdom
| | - Robert W. Henning
- BioCARS, University of Chicago, Building 434B, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439, USA
| | - Diana C. F. Monteiro
- Hauptman–Woodward Medical Research Institute, 700 Ellicott Street, Buffalo, NY 14203-1102, USA
| | - Dean A. Myles
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Shigeki Owada
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Darren A. Sherrell
- Structural Biology Center, X-ray Science Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Megan L. Straw
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Vukica Šrajer
- BioCARS, University of Chicago, Building 434B, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439, USA
| | | | - Kensuke Tono
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Takehiko Tosha
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Ivo Tews
- Biological Sciences, University of Southampton, University Road, Southampton SO17 1BJ, United Kingdom
| | - Martin Trebbin
- Hauptman–Woodward Medical Research Institute, 700 Ellicott Street, Buffalo, NY 14203-1102, USA
- Department of Chemistry, State University of New York at Buffalo, Buffalo, NY 14260, USA
| | - Richard W. Strange
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Kevin L. Weiss
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Jonathan A. R. Worrall
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
| | - Flora Meilleur
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Robin L. Owen
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, United Kingdom
| | - Reza A. Ghiladi
- Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA
| | - Michael A. Hough
- School of Life Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, United Kingdom
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, United Kingdom
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6
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Butrón D, Zamora-Carreras H, Devesa I, Treviño MA, Abian O, Velázquez-Campoy A, Bonache MÁ, Lagartera L, Martín-Martínez M, González-Rodríguez S, Baamonde A, Fernández-Carvajal A, Ferrer-Montiel A, Jiménez MÁ, González-Muñiz R. DD04107-Derived neuronal exocytosis inhibitor peptides: Evidences for synaptotagmin-1 as a putative target. Bioorg Chem 2021; 115:105231. [PMID: 34388485 DOI: 10.1016/j.bioorg.2021.105231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/19/2021] [Accepted: 07/28/2021] [Indexed: 11/25/2022]
Abstract
The analgesic peptide DD04107 (Pal-EEMQRR-NH2) and its acetylated analogue inhibit α-calcitonin gene-related peptide (α-CGRP) exocytotic release from primary sensory neurons. Examining the crystal structure of the SNARE-Synaptotagmin-1(Syt1) complex, we hypothesized that these peptides could inhibit neuronal exocytosis by binding to Syt1, hampering at least partially its interaction with the SNARE complex. To address this hypothesis, we first interrogate the role of individual side-chains on the inhibition of α-CGRP release, finding that E1, M3, Q4 and R6 residues were crucial for activity. CD and NMR conformational analysis showed that linear peptides have tendency to adopt α-helical conformations, but the results with cyclic analogues indicated that this secondary structure is not needed for activity. Isothermal titration calorimetry (ITC) measurements demonstrate a direct interaction of some of these peptides with Syt1-C2B domain, but not with Syt7-C2B region, indicating selectivity. As expected for a compound able to inhibit α-CGRP release, cyclic peptide derivative Pal-E-cyclo[EMQK]R-NH2 showed potent in vivo analgesic activity, in a model of inflammatory pain. Molecular dynamics simulations provided a model consistent with KD values for the interaction of peptides with Syt1-C2B domain, and with their biological activity. Altogether, these results identify Syt1 as a potential new analgesic target.
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Affiliation(s)
- Daniel Butrón
- Instituto de Química Médica (IQM-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain
| | | | - Isabel Devesa
- IDiBE, Universidad Miguel Hernández, Avda. de la Universidad s/n, 03202 Elche, Spain
| | - Miguel A Treviño
- Instituto de Química Física Rocasolano (IQFR-CSIC), Serrano 119, 28006 Madrid, Spain
| | - Olga Abian
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Units IQFR-CSIC-BIFI, and GBsC-CSIC-BIFI, Universidad de Zaragoza, 50018 Zaragoza, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009 Zaragoza, Spain; Biomedical Research Networking Centre for Liver and Digestive Diseases (CIBERehd), Madrid, Spain; Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain; Aragon Health Sciences Institute (IACS), 50009 Zaragoza, Spain
| | - Adrián Velázquez-Campoy
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Units IQFR-CSIC-BIFI, and GBsC-CSIC-BIFI, Universidad de Zaragoza, 50018 Zaragoza, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009 Zaragoza, Spain; Biomedical Research Networking Centre for Liver and Digestive Diseases (CIBERehd), Madrid, Spain; Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain; ARAID Foundation, Government of Aragon, 50018 Zaragoza, Spain
| | - M Ángeles Bonache
- Instituto de Química Médica (IQM-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain
| | - Laura Lagartera
- Instituto de Química Médica (IQM-CSIC), Juan de la Cierva 3, 28006 Madrid, Spain
| | | | | | - Ana Baamonde
- Facultad de Medicina, Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, Julián Clavería 6, 33006 Oviedo, Asturias, Spain
| | | | | | - M Ángeles Jiménez
- Instituto de Química Física Rocasolano (IQFR-CSIC), Serrano 119, 28006 Madrid, Spain.
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Tsegaye S, Dedefo G, Mehdi M. Biophysical applications in structural and molecular biology. Biol Chem 2021; 402:1155-1177. [PMID: 34218543 DOI: 10.1515/hsz-2021-0232] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 05/27/2021] [Indexed: 11/15/2022]
Abstract
The main objective of structural biology is to model proteins and other biological macromolecules and link the structural information to function and dynamics. The biological functions of protein molecules and nucleic acids are inherently dependent on their conformational dynamics. Imaging of individual molecules and their dynamic characteristics is an ample source of knowledge that brings new insights about mechanisms of action. The atomic-resolution structural information on most of the biomolecules has been solved by biophysical techniques; either by X-ray diffraction in single crystals or by nuclear magnetic resonance (NMR) spectroscopy in solution. Cryo-electron microscopy (cryo-EM) is emerging as a new tool for analysis of a larger macromolecule that couldn't be solved by X-ray crystallography or NMR. Now a day's low-resolution Cryo-EM is used in combination with either X-ray crystallography or NMR. The present review intends to provide updated information on applications like X-ray crystallography, cryo-EM and NMR which can be used independently and/or together in solving structures of biological macromolecules for our full comprehension of their biological mechanisms.
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Affiliation(s)
- Solomon Tsegaye
- Department of Biochemistry, College of Health Sciences, Arsi University, Oromia, Ethiopia
| | - Gobena Dedefo
- Department of Medical Laboratory Technology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Mohammed Mehdi
- Department of Biochemistry, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
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Wu Z, Dharan N, McDargh ZA, Thiyagarajan S, O'Shaughnessy B, Karatekin E. The neuronal calcium sensor Synaptotagmin-1 and SNARE proteins cooperate to dilate fusion pores. eLife 2021; 10:68215. [PMID: 34190041 PMCID: PMC8294851 DOI: 10.7554/elife.68215] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [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: 03/09/2021] [Accepted: 06/29/2021] [Indexed: 02/07/2023] Open
Abstract
All membrane fusion reactions proceed through an initial fusion pore, including calcium-triggered release of neurotransmitters and hormones. Expansion of this small pore to release cargo is energetically costly and regulated by cells, but the mechanisms are poorly understood. Here, we show that the neuronal/exocytic calcium sensor Synaptotagmin-1 (Syt1) promotes expansion of fusion pores induced by SNARE proteins. Pore dilation relied on calcium-induced insertion of the tandem C2 domain hydrophobic loops of Syt1 into the membrane, previously shown to reorient the C2 domain. Mathematical modelling suggests that C2B reorientation rotates a bound SNARE complex so that it exerts force on the membranes in a mechanical lever action that increases the height of the fusion pore, provoking pore dilation to offset the bending energy penalty. We conclude that Syt1 exerts novel non-local calcium-dependent mechanical forces on fusion pores that dilate pores and assist neurotransmitter and hormone release.
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Affiliation(s)
- Zhenyong Wu
- Department of Cellular and Molecular Physiology, Yale University, New Haven, United States.,Nanobiology Institute, Yale University, West Haven, United States
| | - Nadiv Dharan
- Department of Chemical Engineering, Columbia University, New York, United States
| | - Zachary A McDargh
- Department of Chemical Engineering, Columbia University, New York, United States
| | - Sathish Thiyagarajan
- Department of Chemical Engineering, Columbia University, New York, United States
| | - Ben O'Shaughnessy
- Department of Chemical Engineering, Columbia University, New York, United States
| | - Erdem Karatekin
- Department of Cellular and Molecular Physiology, Yale University, New Haven, United States.,Nanobiology Institute, Yale University, West Haven, United States.,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, United States.,Saints-Pères Paris Institute for the Neurosciences (SPPIN), Université de Paris, Centre National de la Recherche Scientifique (CNRS) UMR 8003, Paris, France
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9
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Schneider DK, Shi W, Andi B, Jakoncic J, Gao Y, Bhogadi DK, Myers SF, Martins B, Skinner JM, Aishima J, Qian K, Bernstein HJ, Lazo EO, Langdon T, Lara J, Shea-McCarthy G, Idir M, Huang L, Chubar O, Sweet RM, Berman LE, McSweeney S, Fuchs MR. FMX - the Frontier Microfocusing Macromolecular Crystallography Beamline at the National Synchrotron Light Source II. J Synchrotron Radiat 2021; 28:650-665. [PMID: 33650577 PMCID: PMC7941291 DOI: 10.1107/s1600577520016173] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 12/11/2020] [Indexed: 05/26/2023]
Abstract
Two new macromolecular crystallography (MX) beamlines at the National Synchrotron Light Source II, FMX and AMX, opened for general user operation in February 2017 [Schneider et al. (2013). J. Phys. Conf. Ser. 425, 012003; Fuchs et al. (2014). J. Phys. Conf. Ser. 493, 012021; Fuchs et al. (2016). AIP Conf. Proc. SRI2015, 1741, 030006]. FMX, the micro-focusing Frontier MX beamline in sector 17-ID-2 at NSLS-II, covers a 5-30 keV photon energy range and delivers a flux of 4.0 × 1012 photons s-1 at 1 Å into a 1 µm × 1.5 µm to 10 µm × 10 µm (V × H) variable focus, expected to reach 5 × 1012 photons s-1 at final storage-ring current. This flux density surpasses most MX beamlines by nearly two orders of magnitude. The high brightness and microbeam capability of FMX are focused on solving difficult crystallographic challenges. The beamline's flexible design supports a wide range of structure determination methods - serial crystallography on micrometre-sized crystals, raster optimization of diffraction from inhomogeneous crystals, high-resolution data collection from large-unit-cell crystals, room-temperature data collection for crystals that are difficult to freeze and for studying conformational dynamics, and fully automated data collection for sample-screening and ligand-binding studies. FMX's high dose rate reduces data collection times for applications like serial crystallography to minutes rather than hours. With associated sample lifetimes as short as a few milliseconds, new rapid sample-delivery methods have been implemented, such as an ultra-high-speed high-precision piezo scanner goniometer [Gao et al. (2018). J. Synchrotron Rad. 25, 1362-1370], new microcrystal-optimized micromesh well sample holders [Guo et al. (2018). IUCrJ, 5, 238-246] and highly viscous media injectors [Weierstall et al. (2014). Nat. Commun. 5, 3309]. The new beamline pushes the frontier of synchrotron crystallography and enables users to determine structures from difficult-to-crystallize targets like membrane proteins, using previously intractable crystals of a few micrometres in size, and to obtain quality structures from irregular larger crystals.
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Affiliation(s)
| | - Wuxian Shi
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Babak Andi
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jean Jakoncic
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Yuan Gao
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | | | - Stuart F. Myers
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Bruno Martins
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, USA
| | - John M. Skinner
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Jun Aishima
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Kun Qian
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Herbert J. Bernstein
- Ronin Institute for Independent Scholarship, c/o NSLS-II, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Edwin O. Lazo
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Thomas Langdon
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - John Lara
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | | | - Mourad Idir
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Lei Huang
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Oleg Chubar
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Robert M. Sweet
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Lonny E. Berman
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Sean McSweeney
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Martin R. Fuchs
- Photon Sciences, Brookhaven National Laboratory, Upton, NY 11973, USA
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10
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Bykhovskaia M. SNARE complex alters the interactions of the Ca 2+ sensor synaptotagmin 1 with lipid bilayers. Biophys J 2021; 120:642-661. [PMID: 33453271 DOI: 10.1016/j.bpj.2020.12.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 12/19/2020] [Accepted: 12/24/2020] [Indexed: 12/24/2022] Open
Abstract
Release of neuronal transmitters from nerve terminals is triggered by the molecular Ca2+ sensor synaptotagmin 1 (Syt1). Syt1 is a transmembrane protein attached to the synaptic vesicle (SV), and its cytosolic region comprises two domains, C2A and C2B, which are thought to penetrate into lipid bilayers upon Ca2+ binding. Before fusion, SVs become attached to the presynaptic membrane (PM) by the four-helical SNARE complex, which is thought to bind the C2B domain in vivo. To understand how the interactions of Syt1 with lipid bilayers and the SNARE complex trigger fusion, we performed molecular dynamics (MD) simulations at a microsecond scale. We investigated how the isolated C2 modules and the C2AB tandem of Syt1 interact with membranes mimicking either SV or PM. The simulations showed that the C2AB tandem can either bridge SV and PM or insert into PM with its Ca2+-bound tips and that the latter configuration is more favorable. Surprisingly, C2 domains did not cooperate in penetrating into PM but instead mutually hindered their insertion into the bilayer. To test whether the interaction of Syt1 with lipid bilayers could be affected by the C2B-SNARE attachment, we performed systematic conformational analysis of the C2AB-SNARE complex. Notably, we found that the C2B-SNARE interface precludes the coupling of C2 domains and promotes their insertion into PM. We performed the MD simulations of the prefusion protein complex positioned between the lipid bilayers mimicking PM and SV, and our results demonstrated in silico that the presence of the Ca2+ bound C2AB tandem promotes lipid merging. Altogether, our MD simulations elucidated the role of the Syt1-SNARE interactions in the fusion process and produced the dynamic all-atom model of the prefusion protein-lipid complex.
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11
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Mendez D, Bolotovsky R, Bhowmick A, Brewster AS, Kern J, Yano J, Holton JM, Sauter NK. Beyond integration: modeling every pixel to obtain better structure factors from stills. IUCrJ 2020; 7:1151-1167. [PMID: 33209326 PMCID: PMC7642780 DOI: 10.1107/s2052252520013007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/23/2020] [Indexed: 05/25/2023]
Abstract
Most crystallographic data processing methods use pixel integration. In serial femtosecond crystallography (SFX), the intricate interaction between the reciprocal lattice point and the Ewald sphere is integrated out by averaging symmetrically equivalent observations recorded across a large number (104-106) of exposures. Although sufficient for generating biological insights, this approach converges slowly, and using it to accurately measure anomalous differences has proved difficult. This report presents a novel approach for increasing the accuracy of structure factors obtained from SFX data. A physical model describing all observed pixels is defined to a degree of complexity such that it can decouple the various contributions to the pixel intensities. Model dependencies include lattice orientation, unit-cell dimensions, mosaic structure, incident photon spectra and structure factor amplitudes. Maximum likelihood estimation is used to optimize all model parameters. The application of prior knowledge that structure factor amplitudes are positive quantities is included in the form of a reparameterization. The method is tested using a synthesized SFX dataset of ytterbium(III) lysozyme, where each X-ray laser pulse energy is centered at 9034 eV. This energy is 100 eV above the Yb3+ L-III absorption edge, so the anomalous difference signal is stable at 10 electrons despite the inherent energy jitter of each femtosecond X-ray laser pulse. This work demonstrates that this approach allows the determination of anomalous structure factors with very high accuracy while requiring an order-of-magnitude fewer shots than conventional integration-based methods would require to achieve similar results.
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Affiliation(s)
- Derek Mendez
- Molecular Biophysics and Integrated Bioimaging Division (MBIB), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Robert Bolotovsky
- Molecular Biophysics and Integrated Bioimaging Division (MBIB), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Asmit Bhowmick
- Molecular Biophysics and Integrated Bioimaging Division (MBIB), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Aaron S. Brewster
- Molecular Biophysics and Integrated Bioimaging Division (MBIB), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jan Kern
- Molecular Biophysics and Integrated Bioimaging Division (MBIB), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Junko Yano
- Molecular Biophysics and Integrated Bioimaging Division (MBIB), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - James M. Holton
- Molecular Biophysics and Integrated Bioimaging Division (MBIB), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
- Department of Biochemistry and Biophysics, UC San Francisco, San Francisco, CA 94158, USA
| | - Nicholas K. Sauter
- Molecular Biophysics and Integrated Bioimaging Division (MBIB), Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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12
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Prasad R, Zhou HX. Membrane Association and Functional Mechanism of Synaptotagmin-1 in Triggering Vesicle Fusion. Biophys J 2020; 119:1255-1265. [PMID: 32882186 DOI: 10.1016/j.bpj.2020.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 07/23/2020] [Accepted: 08/10/2020] [Indexed: 12/23/2022] Open
Abstract
Upon Ca2+ influx, synaptic vesicles fuse with the presynaptic plasma membrane (PM) to release neurotransmitters. Membrane fusion is triggered by synaptotagmin-1, a transmembrane protein in the vesicle membrane (VM), but the mechanism is under debate. Synaptotagmin-1 contains a single transmembrane helix (TM) and two tandem C2 domains (C2A and C2B). This study aimed to use molecular dynamics simulations to elucidate how Ca2+-bound synaptotagmin-1, by simultaneously associating with VM and PM, brings them together for fusion. Although C2A stably associates with VM via two Ca2+-binding loops, C2B has a propensity to partially dissociate. Importantly, an acidic motif in the TM-C2A linker competes with VM for interacting with C2B, thereby flipping its orientation to face PM. Subsequently, C2B readily associates with PM via a polybasic cluster and a Ca2+-binding loop. The resulting mechanistic model for the triggering of membrane fusion by synaptotagmin-1 reconciles many experimental observations.
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Affiliation(s)
- Ramesh Prasad
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois
| | - Huan-Xiang Zhou
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois; Department of Physics, University of Illinois at Chicago, Chicago, Illinois.
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13
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Barnes CO, Wu Y, Song J, Lin G, Baxter EL, Brewster AS, Nagarajan V, Holmes A, Soltis SM, Sauter NK, Ahn J, Cohen AE, Calero G. The crystal structure of dGTPase reveals the molecular basis of dGTP selectivity. Proc Natl Acad Sci U S A 2019; 116:9333-9. [PMID: 31019074 DOI: 10.1073/pnas.1814999116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
While cellular dNTPases display broad activity toward dNTPs (e.g., SAMHD1), Escherichia coli (Ec)-dGTPase is the only known enzyme that specifically hydrolyzes dGTP. Here, we present methods for highly efficient, fixed-target X-ray free-electron laser data collection, which is broadly applicable to multiple crystal systems including RNA polymerase II complexes, and the free Ec-dGTPase enzyme. Structures of free and bound Ec-dGTPase shed light on the mechanisms of dGTP selectivity, highlighted by a dynamic active site where conformational changes are coupled to dGTP binding. Moreover, despite no sequence homology between Ec-dGTPase and SAMHD1, both enzymes share similar active-site architectures; however, dGTPase residues at the end of the substrate-binding pocket provide dGTP specificity, while a 7-Å cleft separates SAMHD1 residues from dNTP. Deoxynucleotide triphosphohydrolases (dNTPases) play a critical role in cellular survival and DNA replication through the proper maintenance of cellular dNTP pools. While the vast majority of these enzymes display broad activity toward canonical dNTPs, such as the dNTPase SAMHD1 that blocks reverse transcription of retroviruses in macrophages by maintaining dNTP pools at low levels, Escherichia coli (Ec)-dGTPase is the only known enzyme that specifically hydrolyzes dGTP. However, the mechanism behind dGTP selectivity is unclear. Here we present the free-, ligand (dGTP)- and inhibitor (GTP)-bound structures of hexameric Ec-dGTPase, including an X-ray free-electron laser structure of the free Ec-dGTPase enzyme to 3.2 Å. To obtain this structure, we developed a method that applied UV-fluorescence microscopy, video analysis, and highly automated goniometer-based instrumentation to map and rapidly position individual crystals randomly located on fixed target holders, resulting in the highest indexing rates observed for a serial femtosecond crystallography experiment. Our structures show a highly dynamic active site where conformational changes are coupled to substrate (dGTP), but not inhibitor binding, since GTP locks dGTPase in its apo- form. Moreover, despite no sequence homology, Ec-dGTPase and SAMHD1 share similar active-site and HD motif architectures; however, Ec-dGTPase residues at the end of the substrate-binding pocket mimic Watson–Crick interactions providing guanine base specificity, while a 7-Å cleft separates SAMHD1 residues from dNTP bases, abolishing nucleotide-type discrimination. Furthermore, the structures shed light on the mechanism by which long distance binding (25 Å) of single-stranded DNA in an allosteric site primes the active site by conformationally “opening” a tyrosine gate allowing enhanced substrate binding.
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14
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Uervirojnangkoorn M, Lyubimov AY, Zhou Q, Weis WI, Brunger AT. Resolving indexing ambiguities in X-ray free-electron laser diffraction patterns. Acta Crystallogr D Struct Biol 2019; 75:234-241. [PMID: 30821711 PMCID: PMC6400252 DOI: 10.1107/s2059798318013177] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 09/17/2018] [Indexed: 11/23/2022] Open
Abstract
Processing X-ray free-electron laser (XFEL) diffraction images poses challenges, as an XFEL pulse is powerful enough to destroy or damage the diffracting volume and thereby yields only one diffraction image per volume. Moreover, the crystal is stationary during the femtosecond pulse, so reflections are generally only partially recorded. Therefore, each XFEL diffraction image must be scaled individually and, ideally, corrected for partiality prior to merging. An additional complication may arise owing to indexing ambiguities when the symmetry of the Bravais lattice is higher than that of the space group, or when the unit-cell dimensions are similar to each other. Here, an automated method is presented that diagnoses these indexing ambiguities based on the Brehm-Diederichs algorithm [Brehm & Diederichs (2014), Acta Cryst. D70, 101-109] and produces a consistent indexing choice for the large majority of diffraction images. This method was applied to an XFEL diffraction data set measured from crystals of the neuronal SNARE-complexin-1-synaptotagmin-1 complex. After correcting the indexing ambiguities, substantial improvements were observed in the merging statistics and the atomic model refinement R values. This method should be a useful addition to the arsenal of tools for the processing of XFEL diffraction data sets.
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Affiliation(s)
| | - Artem Y. Lyubimov
- Stanford Synchrotron Radiation Laboratory, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Qiangjun Zhou
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA
- Department of Neurology and Neurological Science, Stanford University, Stanford, CA 94305, USA
- Department of Structural Biology, Stanford University, Stanford, CA 94305, USA
- Department of Photon Science, Stanford University, Stanford, CA 94305, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
| | - William I. Weis
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA
- Department of Structural Biology, Stanford University, Stanford, CA 94305, USA
- Department of Photon Science, Stanford University, Stanford, CA 94305, USA
| | - Axel T. Brunger
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
- Stanford Synchrotron Radiation Laboratory, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA
- Department of Neurology and Neurological Science, Stanford University, Stanford, CA 94305, USA
- Department of Structural Biology, Stanford University, Stanford, CA 94305, USA
- Department of Photon Science, Stanford University, Stanford, CA 94305, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
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15
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Kern J, Chatterjee R, Young ID, Fuller FD, Lassalle L, Ibrahim M, Gul S, Fransson T, Brewster AS, Alonso-Mori R, Hussein R, Zhang M, Douthit L, de Lichtenberg C, Cheah MH, Shevela D, Wersig J, Seuffert I, Sokaras D, Pastor E, Weninger C, Kroll T, Sierra RG, Aller P, Butryn A, Orville AM, Liang M, Batyuk A, Koglin JE, Carbajo S, Boutet S, Moriarty NW, Holton JM, Dobbek H, Adams PD, Bergmann U, Sauter NK, Zouni A, Messinger J, Yano J, Yachandra VK. Structures of the intermediates of Kok's photosynthetic water oxidation clock. Nature 2018; 563:421-425. [PMID: 30405241 DOI: 10.1038/s41586-018-0681-2] [Citation(s) in RCA: 297] [Impact Index Per Article: 49.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Accepted: 08/22/2018] [Indexed: 12/18/2022]
Abstract
Inspired by the period-four oscillation in flash-induced oxygen evolution of photosystem II discovered by Joliot in 1969, Kok performed additional experiments and proposed a five-state kinetic model for photosynthetic oxygen evolution, known as Kok's S-state clock or cycle1,2. The model comprises four (meta)stable intermediates (S0, S1, S2 and S3) and one transient S4 state, which precedes dioxygen formation occurring in a concerted reaction from two water-derived oxygens bound at an oxo-bridged tetra manganese calcium (Mn4CaO5) cluster in the oxygen-evolving complex3-7. This reaction is coupled to the two-step reduction and protonation of the mobile plastoquinone QB at the acceptor side of PSII. Here, using serial femtosecond X-ray crystallography and simultaneous X-ray emission spectroscopy with multi-flash visible laser excitation at room temperature, we visualize all (meta)stable states of Kok's cycle as high-resolution structures (2.04-2.08 Å). In addition, we report structures of two transient states at 150 and 400 µs, revealing notable structural changes including the binding of one additional 'water', Ox, during the S2→S3 state transition. Our results suggest that one water ligand to calcium (W3) is directly involved in substrate delivery. The binding of the additional oxygen Ox in the S3 state between Ca and Mn1 supports O-O bond formation mechanisms involving O5 as one substrate, where Ox is either the other substrate oxygen or is perfectly positioned to refill the O5 position during O2 release. Thus, our results exclude peroxo-bond formation in the S3 state, and the nucleophilic attack of W3 onto W2 is unlikely.
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Affiliation(s)
- Jan Kern
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Ruchira Chatterjee
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Iris D Young
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Franklin D Fuller
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Louise Lassalle
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Mohamed Ibrahim
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Sheraz Gul
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Thomas Fransson
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.,Interdisciplinary Center for Scientific Computing, University of Heidelberg, Heidelberg, Germany
| | - Aaron S Brewster
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | | | - Rana Hussein
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Miao Zhang
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Lacey Douthit
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Casper de Lichtenberg
- Institutionen för Kemi, Kemiskt Biologiskt Centrum, Umeå Universitet, Umeå, Sweden.,Department of Chemistry-Ångström, Molecular Biomimetics, Uppsala University, Uppsala, Sweden
| | - Mun Hon Cheah
- Department of Chemistry-Ångström, Molecular Biomimetics, Uppsala University, Uppsala, Sweden
| | - Dmitry Shevela
- Institutionen för Kemi, Kemiskt Biologiskt Centrum, Umeå Universitet, Umeå, Sweden
| | - Julia Wersig
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Ina Seuffert
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | | | - Ernest Pastor
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | | | - Thomas Kroll
- SSRL, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | | | - Pierre Aller
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, UK
| | - Agata Butryn
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, UK
| | - Allen M Orville
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, UK
| | - Mengning Liang
- LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | | | - Jason E Koglin
- LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Sergio Carbajo
- LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | | | - Nigel W Moriarty
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - James M Holton
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,SSRL, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.,Department of Biochemistry and Biophysics, University of California, San Francisco, CA, USA
| | - Holger Dobbek
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Paul D Adams
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Department of Bioengineering, University of California Berkeley, Berkeley, CA, USA
| | - Uwe Bergmann
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - Nicholas K Sauter
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Athina Zouni
- Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany.
| | - Johannes Messinger
- Institutionen för Kemi, Kemiskt Biologiskt Centrum, Umeå Universitet, Umeå, Sweden. .,Department of Chemistry-Ångström, Molecular Biomimetics, Uppsala University, Uppsala, Sweden.
| | - Junko Yano
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
| | - Vittal K Yachandra
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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16
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Opara NL, Mohacsi I, Makita M, Castano-Diez D, Diaz A, Juranić P, Marsh M, Meents A, Milne CJ, Mozzanica A, Padeste C, Panneels V, Sikorski M, Song S, Stahlberg H, Vartiainen I, Vera L, Wang M, Willmott PR, David C. Demonstration of femtosecond X-ray pump X-ray probe diffraction on protein crystals. Struct Dyn 2018; 5:054303. [PMID: 30364211 PMCID: PMC6192410 DOI: 10.1063/1.5050618] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 09/12/2018] [Indexed: 05/24/2023]
Abstract
The development of X-ray free-electron lasers (XFELs) has opened the possibility to investigate the ultrafast dynamics of biomacromolecules using X-ray diffraction. Whereas an increasing number of structures solved by means of serial femtosecond crystallography at XFELs is available, the effect of radiation damage on protein crystals during ultrafast exposures has remained an open question. We used a split-and-delay line based on diffractive X-ray optics at the Linac Coherent Light Source XFEL to investigate the time dependence of X-ray radiation damage to lysozyme crystals. For these tests, crystals were delivered to the X-ray beam using a fixed-target approach. The presented experiments provide probe signals at eight different delay times between 19 and 213 femtoseconds after a single pump event, thereby covering the time-scales relevant for femtosecond serial crystallography. Even though significant impact on the crystals was observed at long time scales after exposure with a single X-ray pulse, the collected diffraction data did not show significant signal reduction that could be assigned to beam damage on the crystals in the sampled time window and resolution range. This observation is in agreement with estimations of the applied radiation dose, which in our experiment was clearly below the values expected to cause damage on the femtosecond time scale. The experiments presented here demonstrate the feasibility of time-resolved pump-multiprobe X-ray diffraction experiments on protein crystals.
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Affiliation(s)
| | | | | | | | - Ana Diaz
- Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
| | - Pavle Juranić
- Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
| | - May Marsh
- Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
| | - Alke Meents
- Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, D-22607 Hamburg, Germany
| | | | - Aldo Mozzanica
- Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
| | | | | | - Marcin Sikorski
- LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - Sanghoon Song
- LCLS, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | | | | | - Laura Vera
- Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
| | - Meitian Wang
- Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
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17
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Winter G, Waterman DG, Parkhurst JM, Brewster AS, Gildea RJ, Gerstel M, Fuentes-Montero L, Vollmar M, Michels-Clark T, Young ID, Sauter NK, Evans G. DIALS: implementation and evaluation of a new integration package. Acta Crystallogr D Struct Biol 2018; 74:85-97. [PMID: 29533234 PMCID: PMC5947772 DOI: 10.1107/s2059798317017235] [Citation(s) in RCA: 642] [Impact Index Per Article: 107.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 11/30/2017] [Indexed: 01/07/2023] Open
Abstract
The DIALS project is a collaboration between Diamond Light Source, Lawrence Berkeley National Laboratory and CCP4 to develop a new software suite for the analysis of crystallographic X-ray diffraction data, initially encompassing spot finding, indexing, refinement and integration. The design, core algorithms and structure of the software are introduced, alongside results from the analysis of data from biological and chemical crystallography experiments.
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Affiliation(s)
- Graeme Winter
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot OX11 0DE, England
| | - David G. Waterman
- STFC Rutherford Appleton Laboratory, Didcot OX11 0FA, England
- CCP4, Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot OX11 0FA, England
| | - James M. Parkhurst
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot OX11 0DE, England
- Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, England
| | - Aaron S. Brewster
- Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Richard J. Gildea
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot OX11 0DE, England
| | - Markus Gerstel
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot OX11 0DE, England
| | - Luis Fuentes-Montero
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot OX11 0DE, England
| | - Melanie Vollmar
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot OX11 0DE, England
| | - Tara Michels-Clark
- Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Iris D. Young
- Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Nicholas K. Sauter
- Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Gwyndaf Evans
- Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot OX11 0DE, England
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18
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Cheng RKY, Abela R, Hennig M. X-ray free electron laser: opportunities for drug discovery. Essays Biochem 2017; 61:529-42. [PMID: 29118098 DOI: 10.1042/EBC20170031] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 10/02/2017] [Accepted: 10/03/2017] [Indexed: 01/16/2023]
Abstract
Past decades have shown the impact of structural information derived from complexes of drug candidates with their protein targets to facilitate the discovery of safe and effective medicines. Despite recent developments in single particle cryo-electron microscopy, X-ray crystallography has been the main method to derive structural information. The unique properties of X-ray free electron laser (XFEL) with unmet peak brilliance and beam focus allow X-ray diffraction data recording and successful structure determination from smaller and weaker diffracting crystals shortening timelines in crystal optimization. To further capitalize on the XFEL advantage, innovations in crystal sample delivery for the X-ray experiment, data collection and processing methods are required. This development was a key contributor to serial crystallography allowing structure determination at room temperature yielding physiologically more relevant structures. Adding the time resolution provided by the femtosecond X-ray pulse will enable monitoring and capturing of dynamic processes of ligand binding and associated conformational changes with great impact to the design of candidate drug compounds.
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Guan Z, Bykhovskaia M, Jorquera RA, Sutton RB, Akbergenova Y, Littleton JT. A synaptotagmin suppressor screen indicates SNARE binding controls the timing and Ca 2+ cooperativity of vesicle fusion. eLife 2017; 6:28409. [PMID: 28895532 PMCID: PMC5617632 DOI: 10.7554/elife.28409] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [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: 05/05/2017] [Accepted: 09/11/2017] [Indexed: 01/05/2023] Open
Abstract
The synaptic vesicle Ca2+ sensor Synaptotagmin binds Ca2+ through its two C2 domains to trigger membrane interactions. Beyond membrane insertion by the C2 domains, other requirements for Synaptotagmin activity are still being elucidated. To identify key residues within Synaptotagmin required for vesicle cycling, we took advantage of observations that mutations in the C2B domain Ca2+-binding pocket dominantly disrupt release from invertebrates to humans. We performed an intragenic screen for suppressors of lethality induced by expression of Synaptotagmin C2B Ca2+-binding mutants in Drosophila. This screen uncovered essential residues within Synaptotagmin that suggest a structural basis for several activities required for fusion, including a C2B surface implicated in SNARE complex interaction that is required for rapid synchronization and Ca2+ cooperativity of vesicle release. Using electrophysiological, morphological and computational characterization of these mutants, we propose a sequence of molecular interactions mediated by Synaptotagmin that promote Ca2+ activation of the synaptic vesicle fusion machinery.
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Affiliation(s)
- Zhuo Guan
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - Maria Bykhovskaia
- Department of Neurology, School of Medicine, Wayne State University, Detroit, United States
| | - Ramon A Jorquera
- Neuroscience Department, Universidad Central del Caribe, Bayamon, Puerto Rico
| | - Roger Bryan Sutton
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, United States
| | - Yulia Akbergenova
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
| | - J Troy Littleton
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, United States.,Department of Biology, Massachusetts Institute of Technology, Cambridge, United States.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, United States
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Thomaston JL, Woldeyes RA, Nakane T, Yamashita A, Tanaka T, Koiwai K, Brewster AS, Barad BA, Chen Y, Lemmin T, Uervirojnangkoorn M, Arima T, Kobayashi J, Masuda T, Suzuki M, Sugahara M, Sauter NK, Tanaka R, Nureki O, Tono K, Joti Y, Nango E, Iwata S, Yumoto F, Fraser JS, DeGrado WF. XFEL structures of the influenza M2 proton channel: Room temperature water networks and insights into proton conduction. Proc Natl Acad Sci U S A 2017; 114:13357-62. [PMID: 28835537 DOI: 10.1073/pnas.1705624114] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The M2 proton channel of influenza A is a drug target that is essential for the reproduction of the flu virus. It is also a model system for the study of selective, unidirectional proton transport across a membrane. Ordered water molecules arranged in "wires" inside the channel pore have been proposed to play a role in both the conduction of protons to the four gating His37 residues and the stabilization of multiple positive charges within the channel. To visualize the solvent in the pore of the channel at room temperature while minimizing the effects of radiation damage, data were collected to a resolution of 1.4 Å using an X-ray free-electron laser (XFEL) at three different pH conditions: pH 5.5, pH 6.5, and pH 8.0. Data were collected on the Inwardopen state, which is an intermediate that accumulates at high protonation of the His37 tetrad. At pH 5.5, a continuous hydrogen-bonded network of water molecules spans the vertical length of the channel, consistent with a Grotthuss mechanism model for proton transport to the His37 tetrad. This ordered solvent at pH 5.5 could act to stabilize the positive charges that build up on the gating His37 tetrad during the proton conduction cycle. The number of ordered pore waters decreases at pH 6.5 and 8.0, where the Inwardopen state is less stable. These studies provide a graphical view of the response of water to a change in charge within a restricted channel environment.
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Wang J, Askerka M, Brudvig GW, Batista VS. Insights into Photosystem II from Isomorphous Difference Fourier Maps of Femtosecond X-ray Diffraction Data and Quantum Mechanics/Molecular Mechanics Structural Models. ACS Energy Lett 2017; 2:397-407. [PMID: 28217747 PMCID: PMC5307371 DOI: 10.1021/acsenergylett.6b00626] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 01/12/2017] [Indexed: 05/30/2023]
Abstract
Understanding structure-function relations in photosystem II (PSII) is important for the development of biomimetic photocatalytic systems. X-ray crystallography, computational modeling, and spectroscopy have played central roles in elucidating the structure and function of PSII. Recent breakthroughs in femtosecond X-ray crystallography offer the possibility of collecting diffraction data from the X-ray free electron laser (XFEL) before radiation damage of the sample, thereby overcoming the main challenge of conventional X-ray diffraction methods. However, the interpretation of XFEL data from PSII intermediates is challenging because of the issues regarding data-processing, uncertainty on the precise positions of light oxygen atoms next to heavy metal centers, and different kinetics of the S-state transition in microcrystals compared to solution. Here, we summarize recent advances and outstanding challenges in PSII structure-function determination with emphasis on the implementation of quantum mechanics/molecular mechanics techniques combined with isomorphous difference Fourier maps, direct methods, and high-resolution spectroscopy.
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Affiliation(s)
- Jimin Wang
- Department
of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520-8114, United States
| | - Mikhail Askerka
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Gary W. Brudvig
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
| | - Victor S. Batista
- Department
of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States
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Guo T, Duan Z, Chen J, Xie C, Wang Y, Chen P, Wang X. Pull-down combined with proteomic strategy reveals functional diversity of synaptotagmin I. PeerJ 2017; 5:e2973. [PMID: 28194317 PMCID: PMC5301975 DOI: 10.7717/peerj.2973] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 10/18/2016] [Accepted: 01/10/2017] [Indexed: 12/05/2022] Open
Abstract
Synaptotagmin I (Syt I) is most abundant in the brain and is involved in multiple cellular processes. Its two C2 domains, C2A and C2B, are the main functional regions. Our present study employed a pull-down combined with proteomic strategy to identify the C2 domain-interacting proteins to comprehensively understand the biological roles of the C2 domains and thus the functional diversity of Syt I. A total of 135 non-redundant proteins interacting with the C2 domains of Syt I were identified. Out of them, 32 and 64 proteins only bound to C2A or C2B domains, respectively, and 39 proteins bound to both of them. Compared with C2A, C2B could bind to many more proteins particularly those involved in synaptic transmission and metabolic regulation. Functional analysis indicated that Syt I may exert impacts by interacting with other proteins on multiple cellular processes, including vesicular membrane trafficking, synaptic transmission, metabolic regulation, catalysis, transmembrane transport and structure formation, etc. These results demonstrate that the functional diversity of Syt I is higher than previously expected, that its two domains may mediate the same and different cellular processes cooperatively or independently, and that C2B domain may play even more important roles than C2A in the functioning of Syt I. This work not only further deepened our understanding of the functional diversity of Syt I and the functional differences between its two C2 domains, but also provided important clues for the further related researches.
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Affiliation(s)
- Tianyao Guo
- Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University , Changsha , Hunan , P. R. of China
| | - Zhigui Duan
- Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University , Changsha , Hunan , P. R. of China
| | - Jia Chen
- Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University , Changsha , Hunan , P. R. of China
| | - Chunliang Xie
- Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University , Changsha , Hunan , P. R. of China
| | - Ying Wang
- Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University , Changsha , Hunan , P. R. of China
| | - Ping Chen
- Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University , Changsha , Hunan , P. R. of China
| | - Xianchun Wang
- Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University , Changsha , Hunan , P. R. of China
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