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Sun SY, Nie L, Zhang J, Fang X, Luo H, Fu C, Wei Z, Tang AH. The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons. Neural Regen Res 2025; 20:209-223. [PMID: 38767486 PMCID: PMC11246154 DOI: 10.4103/1673-5374.391301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 11/07/2023] [Indexed: 05/22/2024] Open
Abstract
JOURNAL/nrgr/04.03/01300535-202501000-00029/figure1/v/2024-05-14T021156Z/r/image-tiff Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory. Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1; however, whether KIF21A modulates dendritic structure and function in neurons remains unknown. In this study, we found that KIF21A was distributed in a subset of dendritic spines, and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines. Furthermore, the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity. Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching, and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1, but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1. Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals' cognitive abilities. Taken together, our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.
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Affiliation(s)
- Shi-Yan Sun
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, Anhui Province, China
| | - Lingyun Nie
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- CAS Center for Excellence in Molecular Cell Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
| | - Jing Zhang
- Department of Neurobiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
- Brain Research Center, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Xue Fang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
| | - Hongmei Luo
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, Anhui Province, China
| | - Chuanhai Fu
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- CAS Center for Excellence in Molecular Cell Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
| | - Zhiyi Wei
- Department of Neurobiology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
- Brain Research Center, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Ai-Hui Tang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui Province, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, Anhui Province, China
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Metzbower SR, Levy AD, Dharmasri PA, Anderson MC, Blanpied TA. Distinct SAP102 and PSD-95 Nano-organization Defines Multiple Types of Synaptic Scaffold Protein Domains at Single Synapses. J Neurosci 2024; 44:e1715232024. [PMID: 38777601 PMCID: PMC11211720 DOI: 10.1523/jneurosci.1715-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 04/30/2024] [Accepted: 05/05/2024] [Indexed: 05/25/2024] Open
Abstract
MAGUK scaffold proteins play a central role in maintaining and modulating synaptic signaling, providing a framework to retain and position receptors, signaling molecules, and other synaptic components. In particular, the MAGUKs SAP102 and PSD-95 are essential for synaptic function at distinct developmental timepoints and perform both overlapping and unique roles. While their similar structures allow for common binding partners, SAP102 is expressed earlier in synapse development and is required for synaptogenesis, whereas PSD-95 expression peaks later and is associated with synapse maturation. PSD-95 and other key synaptic proteins organize into subsynaptic nanodomains that have a significant impact on synaptic transmission, but the nanoscale organization of SAP102 is unknown. How SAP102 is organized within the synapse, and how it relates spatially to PSD-95 on a nanometer scale, could underlie its unique functions and impact how SAP102 scaffolds synaptic proteins. Here we used DNA-PAINT super-resolution microscopy to measure SAP102 nano-organization and its spatial relationship to PSD-95 at individual synapses in mixed-sex rat cultured neurons. We found that like PSD-95, SAP102 accumulates in high-density subsynaptic nanoclusters (NCs). However, SAP102 NCs were smaller and denser than PSD-95 NCs across development. Additionally, only a subset of SAP102 NCs co-organized with PSD-95, revealing MAGUK nanodomains within individual synapses containing either one or both proteins. These MAGUK nanodomain types had distinct NC properties and were differentially enriched with the presynaptic release protein Munc13-1. This organization into both shared and distinct subsynaptic nanodomains may underlie the ability of SAP102 and PSD-95 to perform both common and unique synaptic functions.
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Affiliation(s)
- Sarah R Metzbower
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Aaron D Levy
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Poorna A Dharmasri
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Michael C Anderson
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Thomas A Blanpied
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201
- University of Maryland Medicine Institute for Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, Maryland 21201
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Dharmasri PA, Levy AD, Blanpied TA. Differential nanoscale organization of excitatory synapses onto excitatory vs. inhibitory neurons. Proc Natl Acad Sci U S A 2024; 121:e2315379121. [PMID: 38625946 PMCID: PMC11047112 DOI: 10.1073/pnas.2315379121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 03/14/2024] [Indexed: 04/18/2024] Open
Abstract
A key feature of excitatory synapses is the existence of subsynaptic protein nanoclusters (NCs) whose precise alignment across the cleft in a transsynaptic nanocolumn influences the strength of synaptic transmission. However, whether nanocolumn properties vary between excitatory synapses functioning in different cellular contexts is unknown. We used a combination of confocal and DNA-PAINT super-resolution microscopy to directly compare the organization of shared scaffold proteins at two important excitatory synapses-those forming onto excitatory principal neurons (Ex→Ex synapses) and those forming onto parvalbumin-expressing interneurons (Ex→PV synapses). As in Ex→Ex synapses, we find that in Ex→PV synapses, presynaptic Munc13-1 and postsynaptic PSD-95 both form NCs that demonstrate alignment, underscoring synaptic nanostructure and the transsynaptic nanocolumn as conserved organizational principles of excitatory synapses. Despite the general conservation of these features, we observed specific differences in the characteristics of pre- and postsynaptic Ex→PV nanostructure. Ex→PV synapses contained larger PSDs with fewer PSD-95 NCs when accounting for size than Ex→Ex synapses. Furthermore, the PSD-95 NCs were larger and denser. The identity of the postsynaptic cell was also represented in Munc13-1 organization, as Ex→PV synapses hosted larger Munc13-1 puncta that contained less dense but larger and more numerous Munc13-1 NCs. Moreover, we measured the spatial variability of transsynaptic alignment in these synapse types, revealing protein alignment in Ex→PV synapses over a distinct range of distances compared to Ex→Ex synapses. We conclude that while general principles of nanostructure and alignment are shared, cell-specific elements of nanodomain organization likely contribute to functional diversity of excitatory synapses.
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Affiliation(s)
- Poorna A. Dharmasri
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD21201
- University of Maryland-Medicine Institute of Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, MD21201
| | - Aaron D. Levy
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD21201
- University of Maryland-Medicine Institute of Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, MD21201
| | - Thomas A. Blanpied
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD21201
- University of Maryland-Medicine Institute of Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, MD21201
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Dharmasri PA, DeMarco EM, Anderson MC, Levy AD, Blanpied TA. Loss of postsynaptic NMDARs drives nanoscale reorganization of Munc13-1 and PSD-95. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.12.574705. [PMID: 38260705 PMCID: PMC10802569 DOI: 10.1101/2024.01.12.574705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Nanoscale protein organization within the active zone (AZ) and post-synaptic density (PSD) influences synaptic transmission. Nanoclusters of presynaptic Munc13-1 are associated with readily releasable pool size and neurotransmitter vesicle priming, while postsynaptic PSD-95 nanoclusters coordinate glutamate receptors across from release sites to control their opening probability. Nanocluster number, size, and protein density vary between synapse types and with development and plasticity, supporting a wide range of functional states at the synapse. Whether or how the receptors themselves control this critical architecture remains unclear. One prominent PSD molecular complex is the NMDA receptor (NMDAR). NMDARs coordinate several modes of signaling within synapses, giving them the potential to influence synaptic organization through direct protein interactions or through signaling. We found that loss of NMDARs results in larger synapses that contain smaller, denser, and more numerous PSD-95 nanoclusters. Intriguingly, NMDAR loss also generates retrograde reorganization of the active zone, resulting in denser, more numerous Munc13-1 nanoclusters, more of which are aligned with PSD-95 nanoclusters. Together, these changes to synaptic nanostructure predict stronger AMPA receptor-mediated transmission in the absence of NMDARs. Notably, while prolonged antagonism of NMDAR activity increases Munc13-1 density within nanoclusters, it does not fully recapitulate these trans-synaptic effects. Thus, our results confirm that NMDARs play an important role in maintaining pre- and postsynaptic nanostructure and suggest that both decreased NMDAR expression and suppressed NMDAR activity may exert distinct effects on synaptic function, yet through unique architectural mechanisms.
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Affiliation(s)
- Poorna A Dharmasri
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- University of Maryland Medicine Institute of Neuroscience Discovery, Baltimore, MD, USA
- Current address: Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Emily M DeMarco
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- University of Maryland Medicine Institute of Neuroscience Discovery, Baltimore, MD, USA
| | - Michael C Anderson
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- University of Maryland Medicine Institute of Neuroscience Discovery, Baltimore, MD, USA
| | - Aaron D Levy
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- University of Maryland Medicine Institute of Neuroscience Discovery, Baltimore, MD, USA
| | - Thomas A Blanpied
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- University of Maryland Medicine Institute of Neuroscience Discovery, Baltimore, MD, USA
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Anderson MC, Levy AD, Dharmasri PA, Metzbower SR, Blanpied TA. Trans-synaptic molecular context of NMDA receptor nanodomains. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573055. [PMID: 38187545 PMCID: PMC10769418 DOI: 10.1101/2023.12.22.573055] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Tight coordination of the spatial relationships between protein complexes is required for cellular function. In neuronal synapses, many proteins responsible for neurotransmission organize into subsynaptic nanoclusters whose trans-cellular alignment modulates synaptic signal propagation. However, the spatial relationships between these proteins and NMDA receptors (NMDARs), which are required for learning and memory, remain undefined. Here, we mapped the relationship of key NMDAR subunits to reference proteins in the active zone and postsynaptic density using multiplexed super-resolution DNA-PAINT microscopy. GluN2A and GluN2B subunits formed nanoclusters with diverse configurations that, surprisingly, were not localized near presynaptic vesicle release sites marked by Munc13-1. However, a subset of presynaptic sites was configured to maintain NMDAR activation: these were internally denser, aligned with abundant PSD-95, and associated closely with specific NMDAR nanodomains. This work reveals a new principle regulating NMDAR signaling and suggests that synaptic functional architecture depends on assembly of multiprotein nanodomains whose interior construction is conditional on trans-cellular relationships.
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Affiliation(s)
- Michael C Anderson
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Aaron D Levy
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Poorna A Dharmasri
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
- Current address: Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sarah R Metzbower
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- Current address: Nikon Instruments Inc, Melville, NY, USA
| | - Thomas A Blanpied
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
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Metzbower SR, Dharmasri PA, Levy AD, Anderson MC, Blanpied TA. Distinct SAP102 and PSD-95 nano-organization defines multiple types of synaptic scaffold protein domains at single synapses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.12.557372. [PMID: 37745494 PMCID: PMC10515860 DOI: 10.1101/2023.09.12.557372] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
The MAGUK family of scaffold proteins plays a central role in maintaining and modulating synaptic signaling, providing a framework to retain and position receptors, signaling molecules, and other synaptic components. Of these scaffold proteins, SAP102 and PSD-95 are essential for synaptic function at distinct developmental timepoints and perform overlapping as well as unique roles. While their similar structures allow for common binding partners, SAP102 is expressed earlier in synapse development and is required for synaptogenesis, whereas PSD-95 expression peaks later in development and is associated with synapse maturation. PSD-95 and other key synaptic proteins organize into subsynaptic nanodomains that have a significant impact on synaptic transmission, but the nanoscale organization of SAP102 is unknown. How SAP102 is organized within the synapse, and how it relates spatially to PSD-95 on a nanometer scale, could impact how SAP102 clusters synaptic proteins and underlie its ability to perform its unique functions. Here we used DNA-PAINT super-resolution microscopy to measure SAP102 nano-organization and its spatial relationship to PSD-95 at individual synapses. We found that like PSD-95, SAP102 accumulates in high-density subsynaptic nanoclusters. However, SAP102 nanoclusters were smaller and denser than PSD-95 nanoclusters across development. Additionally, only a subset of SAP102 nanoclusters co-organized with PSD-95, revealing that within individual synapses there are nanodomains that contain either one or both proteins. This organization into both shared and distinct subsynaptic nanodomains may underlie the ability of SAP102 and PSD-95 to perform both common and unique synaptic functions.
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Affiliation(s)
- Sarah R. Metzbower
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Poorna A. Dharmasri
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Aaron D. Levy
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Michael C. Anderson
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Thomas A. Blanpied
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD 21201
- University of Maryland Medicine Institute for Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, MD 21201
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Dharmasri PA, Levy AD, Blanpied TA. Differential nanoscale organization of excitatory synapses onto excitatory vs inhibitory neurons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.06.556279. [PMID: 37732271 PMCID: PMC10508768 DOI: 10.1101/2023.09.06.556279] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
A key feature of excitatory synapses is the existence of subsynaptic protein nanoclusters whose precise alignment across the cleft in a trans-synaptic nanocolumn influences the strength of synaptic transmission. However, whether nanocolumn properties vary between excitatory synapses functioning in different cellular contexts is unknown. We used a combination of confocal and DNA-PAINT super-resolution microscopy to directly compare the organization of shared scaffold proteins at two important excitatory synapses - those forming onto excitatory principal neurons (Ex→Ex synapses) and those forming onto parvalbumin-expressing interneurons (Ex→PV synapses). As in Ex→Ex synapses, we find that in Ex→PV synapses presynaptic Munc13-1 and postsynaptic PSD-95 both form nanoclusters that demonstrate alignment, underscoring synaptic nanostructure and the trans-synaptic nanocolumn as conserved organizational principles of excitatory synapses. Despite the general conservation of these features, we observed specific differences in the characteristics of pre- and postsynaptic Ex→PV nanostructure. Ex→PV synapses contained larger PSDs with fewer PSD-95 NCs when accounting for size than Ex→Ex synapses. Furthermore, the PSD-95 NCs were larger and denser. The identity of the postsynaptic cell also had a retrograde impact on Munc13-1 organization, as Ex→PV synapses hosted larger Munc13-1 puncta that contained less dense but larger and more numerous Munc13-1 NCs. Moreover, we measured the spatial variability of transsynaptic alignment in these synapse types, revealing protein alignment in Ex→PV synapses over a distinct range of distances compared to Ex→Ex synapses. We conclude that while general principles of nanostructure and alignment are shared, cell-specific elements of nanodomain organization likely contribute to functional diversity of excitatory synapses. Understanding the rules of synapse nanodomain assembly, which themselves are cell-type specific, will be essential for illuminating brain network dynamics.
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Affiliation(s)
- Poorna A Dharmasri
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201
- University of Maryland Medicine Institute of Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Aaron D Levy
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- University of Maryland Medicine Institute of Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Thomas A Blanpied
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland 21201
- University of Maryland Medicine Institute of Neuroscience Discovery, University of Maryland School of Medicine, Baltimore, Maryland 21201
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Ramsay HJ, Gookin SE, Ramsey AM, Kareemo DJ, Crosby KC, Stich DG, Olah SS, Actor-Engel HS, Smith KR, Kennedy MJ. AMPA and GABAA receptor nanodomains assemble in the absence of synaptic neurotransmitter release. Front Mol Neurosci 2023; 16:1232795. [PMID: 37602191 PMCID: PMC10435253 DOI: 10.3389/fnmol.2023.1232795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 07/17/2023] [Indexed: 08/22/2023] Open
Abstract
Postsynaptic neurotransmitter receptors and their associated scaffolding proteins assemble into discrete, nanometer-scale subsynaptic domains (SSDs) within the postsynaptic membrane at both excitatory and inhibitory synapses. Intriguingly, postsynaptic receptor SSDs are mirrored by closely apposed presynaptic active zones. These trans-synaptic molecular assemblies are thought to be important for efficient neurotransmission because they concentrate postsynaptic receptors near sites of presynaptic neurotransmitter release. While previous studies have characterized the role of synaptic activity in sculpting the number, size, and distribution of postsynaptic SSDs at established synapses, it remains unknown whether neurotransmitter signaling is required for their initial assembly during synapse development. Here, we evaluated synaptic nano-architecture under conditions where presynaptic neurotransmitter release was blocked prior to, and throughout synaptogenesis with tetanus neurotoxin (TeNT). In agreement with previous work, neurotransmitter release was not required for the formation of excitatory or inhibitory synapses. The overall size of the postsynaptic specialization at both excitatory and inhibitory synapses was reduced at chronically silenced synapses. However, both AMPARs and GABAARs still coalesced into SSDs, along with their respective scaffold proteins. Presynaptic active zone assemblies, defined by RIM1, were smaller and more numerous at silenced synapses, but maintained alignment with postsynaptic AMPAR SSDs. Thus, basic features of synaptic nano-architecture, including assembly of receptors and scaffolds into trans-synaptically aligned structures, are intrinsic properties that can be further regulated by subsequent activity-dependent mechanisms.
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Affiliation(s)
- Harrison J. Ramsay
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
| | - Sara E. Gookin
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
| | - Austin M. Ramsey
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
| | - Dean J. Kareemo
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
| | - Kevin C. Crosby
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
| | - Dominik G. Stich
- Anschutz Medical Campus, Advanced Light Microscopy Core, University of Colorado, Aurora, CO, United States
| | - Samantha S. Olah
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
| | - Hannah S. Actor-Engel
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
| | - Katharine R. Smith
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
| | - Matthew J. Kennedy
- Anschutz Medical Campus, Department of Pharmacology, University of Colorado, Aurora, CO, United States
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Zhu WH, Yang XX, Gou XZ, Fu SM, Chen JH, Gao F, Shen Y, Bi DL, Tang AH. Nanoscale reorganisation of synaptic proteins in Alzheimer's disease. Neuropathol Appl Neurobiol 2023; 49:e12924. [PMID: 37461203 DOI: 10.1111/nan.12924] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 05/30/2023] [Accepted: 06/24/2023] [Indexed: 08/31/2023]
Abstract
AIMS Synaptic strength depends strongly on the subsynaptic organisation of presynaptic transmitter release and postsynaptic receptor densities, and their alterations are expected to underlie pathologies. Although synaptic dysfunctions are common pathogenic traits of Alzheimer's disease (AD), it remains unknown whether synaptic protein nano-organisation is altered in AD. Here, we systematically characterised the alterations in the subsynaptic organisation in cellular and mouse models of AD. METHODS We used immunostaining and super-resolution stochastic optical reconstruction microscopy imaging to quantitatively examine the synaptic protein nano-organisation in both Aβ1-42-treated neuronal cultures and cortical sections from a mouse model of AD, APP23 mice. RESULTS We found that Aβ1-42-treatment of cultured hippocampal neurons decreased the synaptic retention of postsynaptic scaffolds and receptors and disrupted their nanoscale alignment to presynaptic transmitter release sites. In cortical sections, we found that while GluA1 receptors in wild-type mice were organised in subsynaptic nanoclusters with high local densities, receptors in APP23 mice distributed more homogeneously within synapses. This reorganisation, together with the reduced overall receptor density, led to reduced glutamatergic synaptic transmission. Meanwhile, the transsynaptic alignment between presynaptic release-guiding RIM1/2 and postsynaptic scaffolding protein PSD-95 was reduced in APP23 mice. Importantly, these reorganisations were progressive with age and were more pronounced in synapses in close vicinity of Aβ plaques with dense cores. CONCLUSIONS Our study revealed a spatiotemporal-specific reorganisation of synaptic nanostructures in AD and identifies dense-core amyloid plaques as the major local inductor in APP23 mice.
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Affiliation(s)
- Wang-Hui Zhu
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, China
| | - Xiao-Xu Yang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Neurodegenerative Disorder Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China; Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Sciences and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Biomedical Aging Research, University of Science and Technology of China, Hefei, China
| | - Xu-Zhuo Gou
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, China
| | - Shu-Mei Fu
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Neurodegenerative Disorder Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China; Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Sciences and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Biomedical Aging Research, University of Science and Technology of China, Hefei, China
| | - Jia-Hui Chen
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, China
- Anhui Province Key Laboratory of Biomedical Aging Research, University of Science and Technology of China, Hefei, China
| | - Feng Gao
- Neurodegenerative Disorder Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China; Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Sciences and Technology of China, Hefei, China
| | - Yong Shen
- Neurodegenerative Disorder Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China; Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Sciences and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Biomedical Aging Research, University of Science and Technology of China, Hefei, China
- Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, China
| | - Dan-Lei Bi
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, China
- Neurodegenerative Disorder Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China; Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Sciences and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Biomedical Aging Research, University of Science and Technology of China, Hefei, China
- Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, China
| | - Ai-Hui Tang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Brain Function and Disease, Ministry of Education Key Laboratory for Membrane-less Organelles and Cellular Dynamics, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
- Institute of Artificial Intelligence, Hefei Comprehensive National Science Center, Hefei, China
- Neurodegenerative Disorder Research Center, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China; Institute on Aging and Brain Disorders, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Sciences and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Biomedical Aging Research, University of Science and Technology of China, Hefei, China
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Zhang C, Yadav S, Speer CM. The synaptic basis of activity-dependent eye-specific competition. Cell Rep 2023; 42:112085. [PMID: 36753422 PMCID: PMC10404640 DOI: 10.1016/j.celrep.2023.112085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 12/23/2022] [Accepted: 01/24/2023] [Indexed: 02/09/2023] Open
Abstract
Binocular vision requires proper developmental wiring of eye-specific inputs to the brain. In the thalamus, axons from the two eyes initially overlap in the dorsal lateral geniculate nucleus and undergo activity-dependent competition to segregate into target domains. Here, we combine eye-specific tract tracing with volumetric super-resolution imaging to measure the nanoscale molecular reorganization of developing retinogeniculate eye-specific synapses in the mouse brain. We show there are eye-specific differences in presynaptic vesicle pool size and vesicle association with the active zone at the earliest stages of retinogeniculate refinement but find no evidence of eye-specific differences in subsynaptic domain number, size, or transsynaptic alignment across development. Genetic disruption of spontaneous retinal activity decreases retinogeniculate synapse density, delays the emergence eye-specific differences in vesicle organization, and disrupts subsynaptic domain maturation. These results suggest that activity-dependent eye-specific presynaptic maturation underlies synaptic competition in the mammalian visual system.
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Affiliation(s)
- Chenghang Zhang
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Swapnil Yadav
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Colenso M Speer
- Department of Biology, University of Maryland, College Park, MD 20742, USA.
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