1
|
Koff M, Monagas-Valentin P, Novikov B, Chandel I, Panin V. Protein O-mannosylation: one sugar, several pathways, many functions. Glycobiology 2023; 33:911-926. [PMID: 37565810 PMCID: PMC10859634 DOI: 10.1093/glycob/cwad067] [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: 07/16/2023] [Revised: 07/23/2023] [Accepted: 07/31/2023] [Indexed: 08/12/2023] Open
Abstract
Recent research has unveiled numerous important functions of protein glycosylation in development, homeostasis, and diseases. A type of glycosylation taking the center stage is protein O-mannosylation, a posttranslational modification conserved in a wide range of organisms, from yeast to humans. In animals, protein O-mannosylation plays a crucial role in the nervous system, whereas protein O-mannosylation defects cause severe neurological abnormalities and congenital muscular dystrophies. However, the molecular and cellular mechanisms underlying protein O-mannosylation functions and biosynthesis remain not well understood. This review outlines recent studies on protein O-mannosylation while focusing on the functions in the nervous system, summarizes the current knowledge about protein O-mannosylation biosynthesis, and discusses the pathologies associated with protein O-mannosylation defects. The evolutionary perspective revealed by studies in the Drosophila model system are also highlighted. Finally, the review touches upon important knowledge gaps in the field and discusses critical questions for future research on the molecular and cellular mechanisms associated with protein O-mannosylation functions.
Collapse
Affiliation(s)
- Melissa Koff
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| | - Pedro Monagas-Valentin
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| | - Boris Novikov
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| | - Ishita Chandel
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| | - Vladislav Panin
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| |
Collapse
|
2
|
Ermanoska B, Rodal AA. Non-muscle myosin II regulates presynaptic actin assemblies and neuronal mechanobiology. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.10.566609. [PMID: 38014140 PMCID: PMC10680633 DOI: 10.1101/2023.11.10.566609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Neuromuscular junctions (NMJs) are evolutionarily ancient, specialized contacts between neurons and muscles. Axons and NMJs must endure mechanical strain through a lifetime of muscle contraction, making them vulnerable to aging and neurodegenerative conditions. However, cellular strategies for mitigating this mechanical stress remain unknown. In this study, we used Drosophila larval NMJs to investigate the role of actin and myosin (actomyosin)-mediated contractility in generating and responding to cellular forces at the neuron-muscle interface. We identified a new long-lived, low-turnover presynaptic actin core traversing the NMJ, which partly co-localizes with non-muscle myosin II (NMII). Neuronal RNAi of NMII induced disorganization of this core, suggesting that this structure might have contractile properties. Interestingly, neuronal RNAi of NMII also decreased NMII levels in the postsynaptic muscle proximal to neurons, suggesting that neuronal actomyosin rearrangements propagate their effects trans-synaptically. We also observed reduced Integrin levels upon NMII knockdown, indicating that neuronal actomyosin disruption triggers rearrangements of Integrin-mediated connections between neurons and surrounding muscle tissue. In summary, our study identifies a previously uncharacterized presynaptic actomyosin subpopulation that upholds the neuronal mechanical continuum, transmits signals to adjacent muscle tissue, and collaborates with Integrin receptors to govern the mechanobiology of the neuromuscular junction.
Collapse
|
3
|
Dai L, Shen KF, Zhang CQ. Plexin-mediated neuronal development and neuroinflammatory responses in the nervous system. Histol Histopathol 2023; 38:1239-1248. [PMID: 37170703 DOI: 10.14670/hh-18-625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Plexins are a large family of single-pass transmembrane proteins that mediate semaphorin signaling in multiple systems. Plexins were originally characterized for their role modulating cytoskeletal activity to regulate axon guidance during nervous system development. Thereafter, different semaphorin-plexin complexes were identified in the nervous system that have diverse functions in neurons, astrocytes, glia, oligodendrocytes, and brain derived-tumor cells, providing unexpected but meaningful insights into the biological activities of this protein family. Here, we review the overall structure and relevant downstream signaling cascades of plexins. We consider the current knowledge regarding the function of semaphorin-plexin cascades in the nervous system, including the most recent data regarding their roles in neuronal development, neuroinflammation, and glioma.
Collapse
Affiliation(s)
- Lu Dai
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing, China
| | - Kai-Feng Shen
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Chun-Qing Zhang
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, China.
| |
Collapse
|
4
|
Marom S, Marder E. A biophysical perspective on the resilience of neuronal excitability across timescales. Nat Rev Neurosci 2023; 24:640-652. [PMID: 37620600 DOI: 10.1038/s41583-023-00730-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2023] [Indexed: 08/26/2023]
Abstract
Neuronal membrane excitability must be resilient to perturbations that can take place over timescales from milliseconds to months (or even years in long-lived animals). A great deal of attention has been paid to classes of homeostatic mechanisms that contribute to long-term maintenance of neuronal excitability through processes that alter a key structural parameter: the number of ion channel proteins present at the neuronal membrane. However, less attention has been paid to the self-regulating 'automatic' mechanisms that contribute to neuronal resilience by virtue of the kinetic properties of ion channels themselves. Here, we propose that these two sets of mechanisms are complementary instantiations of feedback control, together enabling resilience on a wide range of temporal scales. We further point to several methodological and conceptual challenges entailed in studying these processes - both of which involve enmeshed feedback control loops - and consider the consequences of these mechanisms of resilience.
Collapse
Affiliation(s)
- Shimon Marom
- Faculty of Medicine, Technion - Institute of Technology, Haifa, Israel.
| | - Eve Marder
- Biology Department, Brandeis University, Waltham, MA, USA.
- Volen National Center for Complex Systems, Brandeis University, Waltham, MA, USA.
| |
Collapse
|
5
|
Ramesh N, Escher M, Turrel O, Lützkendorf J, Matkovic T, Liu F, Sigrist SJ. An antagonism between Spinophilin and Syd-1 operates upstream of memory-promoting presynaptic long-term plasticity. eLife 2023; 12:e86084. [PMID: 37767892 PMCID: PMC10588984 DOI: 10.7554/elife.86084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
We still face fundamental gaps in understanding how molecular plastic changes of synapses intersect with circuit operation to define behavioral states. Here, we show that an antagonism between two conserved regulatory proteins, Spinophilin (Spn) and Syd-1, controls presynaptic long-term plasticity and the maintenance of olfactory memories in Drosophila. While Spn mutants could not trigger nanoscopic active zone remodeling under homeostatic challenge and failed to stably potentiate neurotransmitter release, concomitant reduction of Syd-1 rescued all these deficits. The Spn/Syd-1 antagonism converged on active zone close F-actin, and genetic or acute pharmacological depolymerization of F-actin rescued the Spn deficits by allowing access to synaptic vesicle release sites. Within the intrinsic mushroom body neurons, the Spn/Syd-1 antagonism specifically controlled olfactory memory stabilization but not initial learning. Thus, this evolutionarily conserved protein complex controls behaviorally relevant presynaptic long-term plasticity, also observed in the mammalian brain but still enigmatic concerning its molecular mechanisms and behavioral relevance.
Collapse
Affiliation(s)
- Niraja Ramesh
- Institute for Biology/Genetics, Freie Universität BerlinBerlinGermany
| | - Marc Escher
- Institute for Biology/Genetics, Freie Universität BerlinBerlinGermany
| | - Oriane Turrel
- Institute for Biology/Genetics, Freie Universität BerlinBerlinGermany
| | | | - Tanja Matkovic
- Institute for Biology/Genetics, Freie Universität BerlinBerlinGermany
| | - Fan Liu
- Leibniz-Forschungsinstitut für Molekulare PharmakologieBerlinGermany
| | - Stephan J Sigrist
- Institute for Biology/Genetics, Freie Universität BerlinBerlinGermany
| |
Collapse
|
6
|
Rivero-Ríos P, Tsukahara T, Uygun T, Chen A, Chavis GD, Giridharan SSP, Iwase S, Sutton MA, Weisman LS. Recruitment of the SNX17-Retriever recycling pathway regulates synaptic function and plasticity. J Cell Biol 2023; 222:e202207025. [PMID: 37141105 PMCID: PMC10165670 DOI: 10.1083/jcb.202207025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 03/10/2023] [Accepted: 04/11/2023] [Indexed: 05/05/2023] Open
Abstract
Trafficking of cell-surface proteins from endosomes to the plasma membrane is a key mechanism to regulate synaptic function. In non-neuronal cells, proteins recycle to the plasma membrane either via the SNX27-Retromer-WASH pathway or via the recently discovered SNX17-Retriever-CCC-WASH pathway. While SNX27 is responsible for the recycling of key neuronal receptors, the roles of SNX17 in neurons are less understood. Here, using cultured hippocampal neurons, we demonstrate that the SNX17 pathway regulates synaptic function and plasticity. Disruption of this pathway results in a loss of excitatory synapses and prevents structural plasticity during chemical long-term potentiation (cLTP). cLTP drives SNX17 recruitment to synapses, where its roles are in part mediated by regulating the surface expression of β1-integrin. SNX17 recruitment relies on NMDAR activation, CaMKII signaling, and requires binding to the Retriever and PI(3)P. Together, these findings provide molecular insights into the regulation of SNX17 at synapses and define key roles for SNX17 in synaptic maintenance and in regulating enduring forms of synaptic plasticity.
Collapse
Affiliation(s)
- Pilar Rivero-Ríos
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Takao Tsukahara
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, USA
| | - Tunahan Uygun
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Alex Chen
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Garrett D. Chavis
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, USA
- Molecular and Integrative Physiology Graduate Program, University, Ann Arbor, MI, USA
| | - Sai Srinivas Panapakkam Giridharan
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Shigeki Iwase
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
| | - Michael A. Sutton
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
- Molecular and Integrative Physiology Graduate Program, University, Ann Arbor, MI, USA
| | - Lois S. Weisman
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
7
|
Vaikakkara Chithran A, Allan DW, O'Connor TP. Adult expression of Semaphorins and Plexins is essential for motor neuron survival. Sci Rep 2023; 13:5894. [PMID: 37041188 PMCID: PMC10090137 DOI: 10.1038/s41598-023-32943-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 04/05/2023] [Indexed: 04/13/2023] Open
Abstract
Axon guidance cues direct the growth and steering of neuronal growth cones, thus guiding the axons to their targets during development. Nonetheless, after axons have reached their targets and established functional circuits, many mature neurons continue to express these developmental cues. The role of axon guidance cues in the adult nervous system has not been fully elucidated. Using the expression pattern data available on FlyBase, we found that more than 96% of the guidance genes that are expressed in the Drosophila melanogaster embryo continue to be expressed in adults. We utilized the GeneSwitch and TARGET systems to spatiotemporally knockdown the expression of these guidance genes selectively in the adult neurons, once the development was completed. We performed an RNA interference (RNAi) screen against 44 guidance genes in the adult Drosophila nervous system and identified 14 genes that are required for adult survival and normal motility. Additionally, we show that adult expression of Semaphorins and Plexins in motor neurons is necessary for neuronal survival, indicating that guidance genes have critical functions in the mature nervous system.
Collapse
Affiliation(s)
- Aarya Vaikakkara Chithran
- Graduate Program in Neuroscience, University of British Columbia, 3402-2215 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
- Department of Cellular and Physiological Sciences, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Douglas W Allan
- Department of Cellular and Physiological Sciences, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Timothy P O'Connor
- Department of Cellular and Physiological Sciences, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada.
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2215 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada.
| |
Collapse
|
8
|
Toonen RF, Verhage M. Homing in on homeostatic plasticity. Neuron 2022; 110:3645-3647. [PMID: 36395749 DOI: 10.1016/j.neuron.2022.10.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In this issue of Neuron, Orr et al.1 demonstrate a detailed molecular cascade that drives presynaptic homeostatic plasticity and enhances presynaptic vesicle fusion in response to reduced postsynaptic activity. Two large presynaptic signaling complexes are central hubs.
Collapse
Affiliation(s)
- Ruud F Toonen
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Matthijs Verhage
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research (CNCR), Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands; Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research (CNCR), Amsterdam Neuroscience, VU University Medical Center, Amsterdam, the Netherlands.
| |
Collapse
|