Article
Multidisciplinary Sciences
Karolina P. Stepien, Josep Rizo
Summary: The study demonstrates that decreasing the synaptobrevin-to-lipid ratio to very low levels leads to inefficient fusion, but synaptotagmin-1 strongly stimulates fusion under these conditions. Anchoring SNAP-25 on the syntaxin-1 liposomes dramatically enhances fusion efficiency. Additionally, there is a synergy between synaptotagmin-1 and membrane anchoring of SNAP-25, allowing efficient fusion between liposomes with low synaptobrevin densities and low syntaxin-1 densities.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Neurosciences
Zhenyong Wu, Lu Ma, Nicholas A. Courtney, Jie Zhu, Ane Landajuela, Yongli Zhang, Edwin R. Chapman, Erdem Karatekin
Summary: This study aims to explore the critical features of the C2A domain of Syt1 and compare it to the analogous feature in C2B. The research found that both the poly-lysine patches in C2A and C2B contribute to membrane binding, and both are crucial for evoked release.
JOURNAL OF NEUROSCIENCE
(2022)
Review
Biochemistry & Molecular Biology
Monica C. Quinones-Frias, J. Troy Littleton
Summary: The SYT family of proteins play crucial roles in regulating membrane trafficking at neuronal synapses, participating in synchronous and asynchronous fusion of synaptic vesicles and preventing spontaneous release. Changes in SYT isoforms can alter the fusion of synaptic vesicles and regulate trafficking of other subcellular organelles. However, the exact mechanisms by which SYTs interact with lipids and other effectors are still under investigation.
CELLULAR AND MOLECULAR LIFE SCIENCES
(2021)
Article
Biochemistry & Molecular Biology
Ethiene Kwok, Shauna C. Otto, Patricia Khuu, Andrew P. Carpenter, Sara J. Codding, Patrick N. Reardon, Juan Vanegas, Tanushri M. Kumar, Chapman J. Kuykendall, Ryan A. Mehl, Joe Baio, Colin P. Johnson
Summary: Dysferlin, a large membrane protein, plays a crucial role in muscle function. It is associated with muscle diseases and its loss of activity leads to reduced exocytosis and abnormal intracellular Ca2+. In this study, the researchers found that the C2A domain of dysferlin binds preferentially to membranes containing PI(4,5)P2 through specific residues on its concave face. They also discovered that binding of the C2A domain to membranes leads to changes in lipid packing and insertion of certain residues into the membrane. These findings provide insights into the mechanism of dysferlin and its role in membrane binding and Ca2+ regulation.
JOURNAL OF MOLECULAR BIOLOGY
(2023)
Article
Biology
Gerardo Malagon, Jongyun Myeong, Vitaly A. Klyachko
Summary: Asynchronous release in rat hippocampal synapses is divided into two subpopulations, with different spatial and temporal characteristics. These two subpopulations show distinct organization and dynamics compared to synchronous events, particularly in terms of calcium-dependent endocytosis.
Article
Neurosciences
Michael J. Seibert, Chantell S. Evans, Kevin S. Stanley, Zhenyong Wu, Edwin R. Chapman
Summary: SYT9 is a Ca2+ sensor in neuroendocrine cells, but its function in neurons is unclear. In this study, it was found that SYT9 does not trigger rapid synaptic vesicle exocytosis in mouse cortical, hippocampal, or striatal neurons unless it is overexpressed. Loss of SYT9 in striatal neurons reduced the frequency of spontaneous neurotransmitter release events. Further investigation revealed that SYT9 is localized to dense-core vesicles containing substance P, and loss of SYT9 impaired SP release, causing the observed decrease in mini frequency. The study also showed that Ca2+ binding to the C2A domain of SYT9 triggered membrane fusion in vitro, and mutations disrupting this activity abolished SYT9's ability to regulate SP release and mini frequency. Therefore, it can be concluded that SYT9 indirectly regulates synaptic transmission in striatal neurons by controlling SP release.
JOURNAL OF NEUROSCIENCE
(2023)
Article
Biology
Josep Rizo, Levent Sari, Yife Qi, Wonpil Im, Milo M. Lin
Summary: Synaptic vesicles are prepared for fast neurotransmitter release upon calcium binding to Synaptotagmin-1. Molecular dynamics simulations suggest that SNARE complexes induce slow formation of membrane-membrane contact interfaces. The prepared state includes macromolecular assemblies of Synaptotagmin-1 and complexin bound to trans-SNARE complexes.
Article
Biochemistry & Molecular Biology
Klaudia Jaczynska, Luis Esquivies, Richard A. Pfuetzner, Baris Alten, Kyle D. Brewer, Qiangjun Zhou, Ege T. Kavalali, Axel T. Brunger, Josep Rizo
Summary: Characterizing the interactions between Synaptotagmin-1 and the SNARE complex is critical for understanding neurotransmitter release. This study investigates the binding of Synaptotagmin-1 to the SNARE complex through two interfaces, the primary interface and the tripartite interface. The results suggest the need for further research methods to accurately determine the binding mechanism.
Review
Biochemistry & Molecular Biology
Azzurra Margiotta
Summary: The myelin sheath is an important insulating layer around nerves that allows fast and efficient nerve conduction. It is formed by different cells in the central and peripheral nervous system. The myelin sheath's structure and composition play a crucial role in maintaining proper nerve function. The proteins SNAREs and rabs have been found to be involved in regulating myelin formation and maintenance.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Multidisciplinary Sciences
Philipe R. F. Mendonca, Erica Tagliatti, Helen Langley, Dimitrios Kotzadimitriou, Criseida G. Zamora-Chimal, Yulia Timofeeva, Kirill E. Volynski
Summary: This study reveals the variation in synchronous and asynchronous release ratio among synaptic outputs from single pyramidal cells, and demonstrates that low release probability synapses have reduced synchronicity. Additionally, the distribution of asynchronous release sites is more widespread within the release area.
NATURE COMMUNICATIONS
(2022)
Article
Biology
Bin Wang, Olga K. Dudko
Summary: A theory of action-potential-triggered neurotransmitter release is proposed and validated with existing data, showing a universal scaling law in synaptic transmission and the ability to extract unique kinetic and energetic parameters for each synapse. The theory also detects cooperativity among SNARE complexes and establishes connections between molecular constituents of synapses and synaptic function. Additionally, the theory reveals trade-off relations between transmission rate and fidelity, providing insights into the molecular-level properties of synapses in synaptic transmission functions.
Article
Cell Biology
Hao Chen, Zara Y. Weinberg, G. Aditya Kumar, Manojkumar A. Puthenveedu
Summary: Chen et al. discover that VAMP2 is selectively packaged with μ opioid receptors into vesicles and mediates their fusion. This selective packaging allows for individual regulation of GPCR trafficking. This finding provides insight into the fusion machinery responsible for GPCR delivery.
JOURNAL OF CELL BIOLOGY
(2023)
Article
Multidisciplinary Sciences
Murat Kirtay, Josefine Sell, Christian Marx, Holger Haselmann, Mihai Ceanga, Zhong-Wei Zhou, Vahid Rahmati, Joanna Kirkpatrick, Katrin Buder, Paulius Grigaravicius, Alessandro Ori, Christian Geis, Zhao-Qi Wang
Summary: ATR, a key regulator of DNA damage response and replication stress, also plays a role in regulating neuronal activity beyond its known functions. Deletion of ATR in neurons leads to increased intrinsic activity, aberrant firing, and heightened epileptiform activity, potentially increasing susceptibility to ataxia and epilepsy.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Andrew P. Carpenter, Patricia Khuu, Tobias Weidner, Colin P. Johnson, Steven J. Roeters, Joe E. Baio
Summary: Dysferlin plays a critical role in muscle membrane repair by recruiting vesicles to the injured site. Research shows that its binding orientation is influenced by the lipid composition of the membrane.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Biology
Gulcin Vardar, Andrea Salazar-Lazaro, Sina Zobel, Thorsten Trimbuch, Christian Rosenmund
Summary: This study analyzed three groups of STX1A mutations in cultured mouse hippocampal neurons and found that JMD elongations and charge reversal mutations have differential effects on neurotransmitter release. Furthermore, the research showed that STX1A's JMD regulates the palmitoylation of STX1A's TMD, which in turn affects vesicle fusion.
Article
Neurosciences
Brie E. Paddock, Zhao Wang, Laurie M. Biela, Kaiyun Chen, Michael D. Getzy, Amelia Striegel, Janet E. Richmond, Edwin R. Chapman, David E. Featherstone, Noreen E. Reist
JOURNAL OF NEUROSCIENCE
(2011)
Article
Neurosciences
Amelia R. Striegel, Laurie M. Biela, Chantell S. Evans, Zhao Wang, Jillian B. Delehoy, R. Bryan Sutton, Edwin R. Chapman, Noreen E. Reist
JOURNAL OF NEUROSCIENCE
(2012)
Article
Neurosciences
Franco Rossetti, Marcio de Araujo Furtado, Thomas Pak, Keenan Bailey, Mallory Shields, Soma Chanda, Michael Addis, Benjamin D. Robertson, Mark Moffett, Lucille A. Lumley, Debra L. Yourick
Article
Multidisciplinary Sciences
Phillip A. Vanlandingham, Taylor R. Fore, Lerin R. Chastain, Suzanne M. Royer, Hong Bao, Noreen E. Reist, Bing Zhang
Article
Multidisciplinary Sciences
Mallory C. Shields, Matthew R. Bowers, McKenzie M. Fulcer, Madelyn K. Bollig, Patrick J. Rock, Bryan R. Sutton, Alysia D. Vrailas-Mortimer, Hanns Lochmuller, Roger G. Whittaker, Rita Horvath, Noreen E. Reist
Article
Cell Biology
Phillip A. Vanlandingham, Mojgan Padash Barmchi, Suzanne Royer, Rebekah Green, Hong Bao, Noreen Reist, Bing Zhang
Review
Neurosciences
Matthew R. Bowers, Noreen E. Reist
NEUROSCIENCE LETTERS
(2020)
Article
Multidisciplinary Sciences
Matthew R. Bowers, Noreen E. Reist
Article
Surgery
Courtney L. L. Devin, Mishal Gillani, Mallory C. C. Shields, Kyle Eldredge, Walter Kucera, Manali Rupji, Lilia A. A. Purvis, Terrah Jean Paul Olson, Yuan Liu, Anthony Jarc, Seth A. A. Rosen
Summary: We developed and validated a new metric, ratio of economy of motion (rEOM), to assign surgical tasks during dual-console procedures. Task assignment based on video review showed 91.2% agreement with rEOM, which serves as the ground truth. rEOM is an accurate, efficient, and scalable OPI that will benefit all professionals in the field of surgery.
Article
Surgery
Michael Meara, Heidi Pieper, Mallory Shields, Ingrid Woelfel, Theresa Wang, David Renton, Xiaodong Chen
Summary: Teaching residents robotic-assisted inguinal hernia repair (RIHR) is a common practice in surgical training. This study investigated the factors affecting operative time and resident prospective entrustment in RIHR cases. The results showed that attending guidance, resident operative plan and judgment, and resident technical skill contribute to entrustment, while resident team management, technical skill, and attending guidance influence operative time.
SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES
(2023)
Article
Surgery
Georges Kaoukabani, Fahri Gokcal, Abeselom Fanta, Xi Liu, Mallory Shields, Catherine Stricklin, Alexander Friedman, Omar Yusef Kudsi
Summary: This study investigates the relationship between objective performance indicators (OPIs), case complexity, surgical experience, and post-operative complications in robotic cholecystectomy (RC) cases. The findings indicate that factors such as surgeon expertise and case complexity can influence intra-operative behaviors and post-surgical complications.
SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES
(2023)
Article
Surgery
Georges Kaoukabani, Fahri Gokcal, Abeselom Fanta, Xi Liu, Mallory Shields, Catherine Stricklin, Alexander Friedman, Omar Yusef Kudsi
Summary: This study is the first to establish the association between OPIs, case complexities, and clinical complications in robotic cholecystectomy (RC). The findings reveal differences in intra-operative behaviors and post-surgical complications dependent on surgeon expertise and case complexity, suggesting the need for standardized assessments of teaching cases, surgical behaviors, and case complexities.
SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES
(2023)