Non-microtubule tubulin-based backbone and subordinate components of postsynaptic density lattices

A purification protocol was developed to identify and analyze the component proteins of a postsynaptic density (PSD) lattice, a core structure of the PSD of excitatory synapses in the central nervous system. “Enriched”- and “lean”-type PSD lattices were purified by synaptic plasma membrane treatment to identify the protein components by comprehensive shotgun mass spectrometry and group them into minimum essential cytoskeleton (MEC) and non-MEC components. Tubulin was found to be a major component of the MEC, with non-microtubule tubulin widely distributed on the purified PSD lattice. The presence of tubulin in and around PSDs was verified by post-embedding immunogold labeling EM of cerebral cortex. Non-MEC proteins included various typical scaffold/adaptor PSD proteins and other class PSD proteins. Thus, this study provides a new PSD lattice model consisting of non-microtubule tubulin-based backbone and various non-MEC proteins. Our findings suggest that tubulin is a key component constructing the backbone and that the associated components are essential for the versatile functions of the PSD.

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Three-dimensional structure of dendritic spines, neuronal specializations that impart both stability and flexibility to synaptic function

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146308 ◽

1993 ◽

Vol 51 ◽

pp. 92-93

Author(s):

Kristen M. Harris

Keyword(s):

Dendritic Spines ◽

Three Dimensional ◽

Synaptic Function ◽

Dimensional Structure ◽

Excitatory Synapses ◽

Concept Of Function ◽

Section Electron ◽

High Quality Information ◽

The Central Nervous System ◽

Mathematical Analyses

Dendritic spines are the tiny protrusions that stud the surface of many neurons and they are the location of over 90% of all excitatory synapses that occur in the central nervous system. Their small size and variable shapes has in large part made detailed study of their structure refractory to conventional light microscopy and single section electron microscopy (EM). Yet their widespread occurrence and likely involvement in learning and memory has motivated extensive efforts to obtain quantitative descriptions of spines in both steady state and dynamic conditions. Since the seminal mathematical analyses of D’Arcy Thompson, the power of establishing quantitatively key parameters of structure has become recognized as a foundation of successful biological inquiry. For dendritic spines highly precise determinations of structure and its variation are proving themselves as the kingpin for establishing a valid concept of function. The recent conjunction of high quality information about the structure, function, and theoretical implications of dendritic spines has produced a flurry of new considerations of their role in synaptic transmission.

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Detection, Identification and Structural Elucidation of Flavonoids using Liquid Chromatography Coupled to Mass Spectrometry

Current Organic Chemistry ◽

10.2174/1385272824666200123104815 ◽

2020 ◽

Vol 24 (1) ◽

pp. 104-112 ◽

Cited By ~ 1

Author(s):

Krzysztof Kamil Wojtanowski ◽

Tomasz Mroczek

Keyword(s):

Mass Spectrometry ◽

Central Nervous System ◽

Nuclear Magnetic Resonance ◽

Liquid Chromatography ◽

High Performance ◽

Short Review ◽

Structural Elucidation ◽

High Throughput Analysis ◽

Protective Actions ◽

The Central Nervous System

Flavonoids are one of the most common secondary metabolites occurring in plants. Their activity in the Central Nervous System (CNS) including sedative, anxiolytic, anti-convulsive, anti-depressant and neuro-protective actions is well known and documented. The most popular methods for detection, identification and structural elucidation of flavonoids are these based on Nuclear Magnetic Resonance (NMR) and mass spectrometry (MS). NMR allows rapid, high throughput analysis of crude extracts and also gives stereochemical details about identified substances. However, these methods are expensive and less sensitive than MS-based techniques. Combining High Performance Liquid Chromatography (HPLC) with MS detection gives the most powerful tool for analysis of flavonoids occurring in plants. There is a lot of different approaches to use LC/MS based techniques for identification of flavonoids and this short review shows the most important.

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Profiling of mouse macrophage lipidome using direct infusion shotgun mass spectrometry

STAR Protocols ◽

10.1016/j.xpro.2020.100235 ◽

2021 ◽

Vol 2 (1) ◽

pp. 100235

Author(s):

Wei-Yuan Hsieh ◽

Kevin J. Williams ◽

Baolong Su ◽

Steven J. Bensinger

Keyword(s):

Mass Spectrometry ◽

Mouse Macrophage ◽

Direct Infusion ◽

Shotgun Mass Spectrometry

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Emerging Synaptic Molecules as Candidates in the Etiology of Neurological Disorders

Neural Plasticity ◽

10.1155/2017/8081758 ◽

2017 ◽

Vol 2017 ◽

pp. 1-25 ◽

Cited By ~ 25

Author(s):

Viviana I. Torres ◽

Daniela Vallejo ◽

Nibaldo C. Inestrosa

Keyword(s):

Central Nervous System ◽

Neurological Disorders ◽

Neuronal Development ◽

Protein Complexes ◽

Synaptic Proteins ◽

Excitatory Synapses ◽

Complex Structures ◽

Disease Phenotype ◽

The Central Nervous System ◽

Invertebrate Models

Synapses are complex structures that allow communication between neurons in the central nervous system. Studies conducted in vertebrate and invertebrate models have contributed to the knowledge of the function of synaptic proteins. The functional synapse requires numerous protein complexes with specialized functions that are regulated in space and time to allow synaptic plasticity. However, their interplay during neuronal development, learning, and memory is poorly understood. Accumulating evidence links synapse proteins to neurodevelopmental, neuropsychiatric, and neurodegenerative diseases. In this review, we describe the way in which several proteins that participate in cell adhesion, scaffolding, exocytosis, and neurotransmitter reception from presynaptic and postsynaptic compartments, mainly from excitatory synapses, have been associated with several synaptopathies, and we relate their functions to the disease phenotype.

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B7-H3 in Medulloblastoma-Derived Exosomes; A Novel Tumorigenic Role

International Journal of Molecular Sciences ◽

10.3390/ijms21197050 ◽

2020 ◽

Vol 21 (19) ◽

pp. 7050

Author(s):

Ian J. Purvis ◽

Kiran K. Velpula ◽

Maheedhara R. Guda ◽

Daniel Nguyen ◽

Andrew J. Tsung ◽

...

Keyword(s):

Mass Spectrometry ◽

Pediatric Cancer ◽

Cultured Cells ◽

Pi3k Pathway ◽

Target Cells ◽

Life Outcomes ◽

Serum Free ◽

Donor Cells ◽

The Central Nervous System ◽

Free Media

(1) Aim: Medulloblastoma is the most common aggressive pediatric cancer of the central nervous system. Improved therapies are necessary to improve life outcomes for medulloblastoma patients. Exosomes are a subset of extracellular vesicles that are excreted outside of the cell, and can transport nucleic acids and proteins from donor cells to nearby recipient cells of the same or dissimilar tissues. Few publications exist exploring the role that exosomes play in medulloblastoma pathogenesis. In this study, we found B7-H3, an immunosuppressive immune checkpoint, present in D283 cell-derived exosomes. (2) Methods: Utilizing mass spectrometry and immunoblotting, the presence of B7-H3 in D283 control and B7-H3 overexpressing exosomes was confirmed. Exosomes were isolated by Systems Biosciences from cultured cells as well as with an isolation kit that included ultracentrifugation steps. Overlay experiments were performed to determine mechanistic impact of exosomes on recipient cells by incubating isolated exosomes in serum-free media with target cells. Impact of D283 exosome incubation on endothelial and UW228 medulloblastoma cells was assessed by immunoblotting. Immunocytochemistry was employed to visualize exosome fusion with recipient cells. (3) Results: Overexpressing B7-H3 in D283 cells increases exosomal production and size distribution. Mass spectrometry revealed a host of novel, pathogenic molecules associated with B7-H3 in these exosomes including STAT3, CCL5, MMP9, and PI3K pathway molecules. Additionally, endothelial and UW228 cells incubated with D283-derived B7-H3-overexpressing exosomes induced B7-H3 expression while pSTAT1 levels decreased in UW228 cells. (4) Conclusions: In total, our results reveal a novel role in exosome production and packaging for B7-H3 that may contribute to medulloblastoma progression.

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