Courtney KC, Wu L, Mandal T, Swift M, Zhang Z, Alaghemandi M, Wu Z, Bradberry MM, Deo C, Lavis LD, Volkmann N, Hanein D, Cui Q, Bao H, Chapman ER. The complexin C-terminal amphipathic helix stabilizes the fusion pore open state by sculpting membranes.Nat Struct Mol Biol. 2022 Feb 7. doi: 10.1038/s41594-021-00716-0. Online ahead of print.PMID: 35132256
Press Release: This protein can shred our cells. Or it can help us think.
Bradberry MM, Mishra S, Zhang Z, Wu L, McKetney JM, Vestling MM, Coon JJ, Chapman ER. Rapid and gentle immunopurification of brain synaptic vesicles. J Neurosci. 2022 Mar 16;JN-RM-2521-21. doi: 10.1523/JNEUROSCI.2521-21.2022. Online ahead of print. PMID: 35296545
Vevea JD, Kusick GF, Courtney KC, Chen E, Watanabe S, Chapman ER. Synaptotagmin 7 is targeted to the axonal plasma membrane through γ-secretase processing to promote synaptic vesicle docking in mouse hippocampal neurons. Elife. 2021 Sep 20;10:e67261. doi: 10.7554/eLife.67261. PMID: 34543184
Liu L, Courtney KC, Huth SW, Rank LA, Weisblum B, Chapman ER, Gellman SH.. Beyond Amphiphilic Balance: Changing Subunit Stereochemistry Alters the Pore-Forming Activity of Nylon-3 Polymers. J Am Chem Soc. 2021 Mar 3;143(8):3219-3230.doi: 10.1021/jacs.0c12731. Epub 2021 Feb 21. PMID: 33611913
Selected to be featured in ACS Editors’ Choice, including a LiveSlides presentation.
Bradberry MM, Courtney NA, Dominguez MJ, Lofquist SM, Knox AT, Sutton RB, Chapman ER.. Molecular Basis for Synaptotagmin-1-Associated Neurodevelopmental Disorder. Neuron. 2020 Apr 21. pii: S0896-6273(20)30272-5. doi: 10.1016/j.neuron.2020.04.003. [Epub ahead of print] PMID: 32362337
Das D, Bao H, Courtney KC, Wu L, Chapman ER. Resolving kinetic intermediates during the regulated assembly and disassembly of fusion pores. Nat Commun. 2020 Jan 13;11(1):231. doi: 10.1038/s41467-019-14072-7. PMID: 31932584
Courtney NA, Bao H, Briguglio JS, Chapman ER.. Synaptotagmin 1 clamps synaptic vesicle fusion in mammalian neurons independent of complexin. Nat Commun. 2019 Sep 9;10(1):4076. doi: 10.1038/s41467-019-12015-w. PMID: 31501440
Press Release: “Clamp” regulates message transfer between mammal neurons
Ruhl DA, Bomba-Warczak E, Watson ET, Bradberry MM, Peterson TA, Basu T, Frelka A, Evans CS, Briguglio JS, Basta T, Stowell MHB, Savas JN, Roopra A, Pearce RA, Piper RC, Chapman ER. Synaptotagmin 17 controls neurite outgrowth and synaptic physiology via distinct cellular pathways. Nat Commun. 2019 Aug 6;10(1):3532. doi: 10.1038/s41467-019-11459-4. PMID: 31387992
Press Release: Remembering Is Important, but Forgetting Is Important, Too
Quarterly Magazine: Single Protein Plays Dual Transport Role In The Brain
Courtney NA, Briguglio JS, Bradberry MM, Greer C, Chapman ER. Excitatory and Inhibitory Neurons Utilize Different Ca2+ Sensors and Sources to Regulate Spontaneous Release. Neuron. 2018 Jun 6;98(5):977-991.e5. doi: 10.1016/j.neuron.2018.04.022. Epub 2018 May 10. PMID: 29754754
Bao H, Das D, Courtney NA, Jiang Y, Briguglio JS, Lou X, Roston D, Cui Q, Chanda B, Chapman ER. Dynamics and number of trans-SNARE complexes determine nascent fusion pore properties. Nature. 2018 Feb 8;554(7691):260-263. doi: 10.1038/nature25481. Epub 2018 Jan 31. PMID: 29420480
“This study by Huan Bao et al. found that more SNARE molecules facilitates fusion pore expansion. Meanwhile, cytosolic VAMP2 fragments and SNAP25 truncation mutations pushed the flickering pores towards close-form. These results suggest that the pore opening and tran-SNARE complexes formation are dynamic, reversible and correlated. Regulation of these molecular dynamics may thus be a physiological mechanism to regulate exocytosis. In addition, the combination of nanodiscs and planar lipid bilayer electrophysiology developed in this work is a well-designed novel technique that achieves microsecond resolution in recording the fusion pore formation. This technique may push the field one step further in understanding the fusion pore opening in a more quantitative, accurate and fast way. Very novel work! Highly recommended.”
– Ling-Gang Wu and Chen Ji, National Institute of Neurological Disorders and Stroke, National Institutes of Health
“One of the most beautiful papers I have ever read on the dynamics of fusion pores and the effect of SNARE numbers observed in a reconstituted system.”
– Yongli Zhang, Yale University New Haven, CT
Bomba-Warczak E, Vevea JD, Brittain JM, Figueroa-Bernier A, Tepp WH, Johnson EA, Yeh FL,Chapman ER. Interneuronal Transfer and Distal Action of Tetanus Toxin and Botulinum Neurotoxins A and D in Central Neurons. Cell Rep. 2016 Aug 16;16(7):1974-87. doi: 10.1016/j.celrep.2016.06.104. Epub 2016 Aug 4. PMID: 27498860
Press Release: Is Botox as safe as we think it is?
Bao H, Goldschen-Ohm M, Jeggle P, Chanda B, Edwardson JM, Chapman ER. Exocytotic fusion pores are composed of both lipids and proteins. Nat Struct Mol Biol. 2016 Jan;23(1):67-73. doi: 10.1038/nsmb.3141. Epub 2015 Dec 14. PMID: 26656855
Press Release: Mystery of the Fusion Pore
Evans, CE, Ruhl, DA, Chapman, ER. An Engineered metal sensor tunes the kinetics of synaptic transmission. J Neurosci. 2015 Aug;35(34):11769-79. doi: 10.1523/JNEUROSCI.1694-15.2015. PMID: 26311762
Press Release: How Fast Do Your Nerve Cells Talk?
Liu H, Bai H, Xue R, Takahashi H, Edwardson JM, Chapman ER. Linker mutations reveal the complexity of synaptotagmin 1 action during synaptic transmission. Nat Neurosci. 2014 May;17(5):670-7. doi: 10.1038/nn.3681. Epub 2014 Mar 23. PMID: 24657966
Liu H, Bai H, Hui E, Yang L, Evans CS, Wang Z, Kwon SE, Chapman ER. Synaptotagmin 7 functions as a Ca2+-sensor for synaptic vesicle replenishment. Elife. 2014 Feb 25;3:e01524. doi: 10.7554/eLife.01524. PMID: 24569478
Featured in HHMI Bulletin, Spring 2014 (27):
…”HHMI Investigator Edwin Chapman and his team at the University of Wisconsin recently showed that two calcium-binding proteins, calmodulin and synaptotagmin 7, work together to ensure that neurons have adequate vesicles for communication.
Yao J, Kwon SE, Gaffaney JD, Dunning FM, Chapman ER. Uncoupling the roles of synaptotagmin I during endo- and exocytosis of synaptic vesicles. Nat Neurosci. 2011 Dec 25.
“Very nice evidence that synaptotagmin I acts as a calcium sensor driving endocytosis in addition to its major role in calcium-dependent transmitter release (exocytosis).”
– Jeff Isaacson, University of California, San Diego
Yao J, Gaffaney JD, Kwon SE, Chapman ER. (2011). Doc2 is a Ca2+-sensor required for asynchronous neurotransmitter release. Cell 147(3):666-77.
Press Release: Dueling Ca2+ Sensors in Neurotransmitter Release
“This interesting paper provides evidence to support a second, kinetically distinct calcium sensor that contrasts to synaptotagmin 1 as sensor for fast (synchronous) release and identifies this second sensor as Doc2, responsible for delayed/prolonged (asynchronous) release of neurotransmitter.
Doc2 is a double C2 domain protein that the present studies show it has the appropriate binding associations, membrane fusion properties, slow binding and off-kinetics, plus correlated changes in asynchronous release in cultured hippocampal neurons using knockdown, knockout and overexpression strategies. This important advance offers focus for studies on a new molecular actor that should drive in vivo work on functional consequences of Doc2 and differential time domains of release in central neurotransmission.”
– Michael Anderson, Oregon Health and Science University
Sun S, Suresh S, Liu H, Tepp WH, Johnson EA, Edwardson JM, Chapman ER. (2011). Receptor binding enables botulinum neurotoxin B to sense low pH for translocation channel assembly. Cell Host & Microbe 10(3):237-47.
Press Release: To Translocate or Not: That Is the Problem
Yeh F, Zhu Y, Tepp WH, Johnson EA, Bertics PJ, Chapman ER. Retargeted Clostridial Neurotoxins as Novel Agents for Treating Chronic Diseases Biochemistry 50(48):10419-21.
Press Release: Botulinum Toxins Could Soothe Inflammation
Kwon SE and Chapman ER. Synaptophysin regulates the kinetics of synaptic vesicle endocytosis in central neurons.Neuron. 2011 Jun 9; 70(5):847-54
“Synaptophysin was one of the first synaptic vesicle membrane proteins characterized. However, its function has remained elusive. This study is interesting, because it is the first to provide evidence that synaptophysin is required for synaptic vesicle endocytosis to proceed at normal rates.”
– Eileen Lafer, University of Texas Health Sciences Center
Hui E, Johnson CP, Yao J, Dunning FM, Chapman ER. Synaptotagmin-Mediated Bending of the Target Membrane Is a Critical Step in Ca2+-Regulated Fusion. Cell. 21 August, 2009. Volume 138, Issue 4: 709-721.
Press Release: A New ‘Bent’ On Fusion
“Local membrane bending really is a central step in the fusion of two bilayers in at least some biological systems, and this bending can be achieved by proteins such as synaptotagmin. Many biophysical studies of bilayer fusion using pure lipid-based systems have been predicated on the idea that fusion in these systems is relevant to biological fusion. I think that this paper provides nice support for that idea, and thereby provides a useful bridge between the biology and the biophysical chemistry of membrane fusion.”
– Jan Hoh, Johns Hopkins School of Medicine
“This paper shows that the fusion of two lipids, the central step of presynaptic neurotransmitter release, is at least facilitated by the action of synaptotagmin (syt). This work represents an important breakthrough in determining the contribution of lipids to neurotransmitter release.”
– Jens Rettig, Universitaet des Saarlandes, Germany
“Employing keen scientific reasoning and a brilliant arsenal of experimental techniques, Hui and colleagues show that synaptotagmin (syt1), in addition to its role in vesicular tethering and Ca2+-sensing, also functions to induce curvature in the target membrane, thereby lowering the energy barrier inherent in vesicle fusion.”
– Fred Mast and Richard Rachubinski, University of Alberta, Canada
Zhang Z, Bhalla A, Dean C, Chapman ER, Jackson MB. (2009). Synaptotagmin IV: a multifunctional regulator of peptidergic nerve terminals. Nature Neuroscience. 12(2): 163-171.
Chicka MC, Hui E, Liu H, Chapman ER. Synaptotagmin arrests the SNARE complex before triggering fast, efficient membrane fusion in response to Ca2+. Nat Struct Mol Biol. 2008 Aug;15(8):827-35.
“This paper nicely shows that synaptotagmin not only initiates vesicle fusion upon calcium (Ca) entry, but also reduces soluble NSF attachment protein receptor (SNARE)-mediated vesicle fusion before Ca entry. Synaptotagmin seems to be at least part of the long-sought negative clamp which inhibits spontaneous SNARE-mediated fusion of synaptic vesicles.” More…
– Jens Rettig: Faculty of 1000 Biology
Dong M, Yeh F, Tepp WH, Dean C, Johnson EA, Janz R, Chapman ER. SV2 is the protein receptor for botulinum neurotoxin A. Science. 2006 Apr 28;312(5773):592-6..
Press Release: A Neuronal Receptor for Botulinum Toxin