The major myelin protein expressed by the peripheral nervous system Schwann cells is protein zero (P0), which represents 50 % of the total protein content in myelin. This 30-kDa integral membrane protein consists of an immunoglobulin (Ig)-like domain, a transmembrane helix, and a 69-residue C-terminal cytoplasmic tail (P0ct). The basic residues in P0ct contribute to the tight packing of myelin lipid bilayers, and alterations in the tail affect how P0 functions as an adhesion molecule necessary for the stability of compact myelin. Several neurodegenerative neuropathies are related to P0, including the more common Charcot-Marie-Tooth disease (CMT) and Dejerine-Sottas syndrome (DSS) as well as rare cases of motor and sensory polyneuropathy. We found that high P0ct concentrations affected the membrane properties of bicelles and induced a lamellar-to-inverted hexagonal phase transition, which caused bicelles to fuse into long, protein-containing filament-like structures. These structures likely reflect the formation of semicrystalline lipid domains with potential relevance for myelination. Not only is P0ct important for stacking lipid membranes, but time-lapse fluorescence microscopy also shows that it might affect membrane properties during myelination. We further describe recombinant production and low-resolution structural characterisation of full-length human P0. Our findings shed light on P0ct effects on membrane properties, and with the successful purification of full-length P0, we have new tools to study the role of P0 in myelin formation and maintenance in vitro. 

The cytoplasmic tail of myelin protein zero induces morphological changes in lipid membranes

Abstract The major myelin protein expressed by the peripheral nervous system Schwann cells is protein zero (P0), representing 50% of the total protein content in myelin. This 30-kDa integral membrane protein consists of an immunoglobulin (Ig)-like domain, a transmembrane helix, and a 69-residue C-terminal cytoplasmic tail (P0ct). The basic residues in P0ct contribute to the tight packing of the myelin lipid bilayers, and alterations in the tail affect how P0 functions as an adhesion molecule necessary for the stability of compact myelin. Several neurodegenerative neuropathies are related to P0, including the more common Charcot-Marie-Tooth disease (CMT) and Dejerine-Sottas syndrome (DSS), but also rare cases of motor and sensory polyneuropathy. We find that high P0ct concentrations affect the membrane properties of bicelles and induce a lamellar-to-inverted hexagonal phase transition, which causes the bicelles to fuse into long, protein-containing filament-like structures. These structures likely reflect the formation of semi-crystalline lipid domains of potential relevance for myelination. Not only is P0ct important for stacking lipid membranes, but time-lapse fluorescence microscopy shows that it might affect membrane properties during myelination. We further describe recombinant production and low-resolution structural characterization of full-length human P0. Our findings shed light on P0ct effects on membrane properties, and with successful purification of full-length P0, we have new tools to study in vitro the role P0 has in myelin formation and maintenance. 

pdf/the-cytoplasmic-tail-of-myelin-protein-zero-induces-1xok4z3ql5.pdf

We use small-angle neutron scattering (SANS) to investigate the structure and phase behavior of a complex fluid within meso- and macroporous matrices. 

Confinement induced change of microemulsion phase structure in controlled pore glass (CPG) monoliths

Myelin is a proteolipid membrane multilayer held together by a set of proteins. The proper formation and function of the myelin sheath relies on the coordinated action of several key myelin proteins. Research exploring how proteins from the peripheral myelin cytoplasmic apposition - myelin basic protein (MBP), the cytoplasmic tail of myelin protein zero (P0ct), and peripheral myelin protein 2 (P2) - interact with each other and with myelin-like membranes was conducted using various techniques, such as small-angle X-ray diffraction (SAXD), differential scanning calorimetry (DSC), surface plasmon resonance (SPR), as well as electron and live epifluorescence microscopy. DSC revealed changes in lipid interactions depending on the protein combination, with MBP and P0ct binding more tightly to lipid membranes than P2, resulting in altered membrane fluidity and stability. These results were supported by SPR, which indicated that the myelin proteins may compete for membrane surface binding. Analysis of the Bragg peaks induced by the myelin proteins in lipidic environments showed both lamellar and non-lamellar phases in protein-lipid complexes. The results indicate both synergy and competition between the three main proteins residing in the PNS myelin major dense line. Furthermore, the observed direct effects of myelin proteins on lipid membrane properties may be relevant to their function in myelinating cells. 

On the synergy between myelin proteins P0, MBP, and P2 in peripheral nerve major dense line formation

Abstract Polymer cubosomes (PCs) are an emerging class of mesoporous microparticles that are produced through solution self‐assembly of highly asymmetric block copolymers (BCPs). They proved useful for encapsulation or templating replicas for catalysis and energy storage. Although PCs made from BCPs with intrinsic functions such as response to stimuli, degradation, or coordination canopen their use for more diverse applications, reports on PCs with innate functions are still rare. Herein, PCs based on organometallic BCPs bearing pendant ferrocene moieties is reported. The poly(ethylene oxide)‐ block ‐poly(2‐(methacryoyloxy)ethyl ferrocene carboxylate) BCPs (PEO 44 ‐ b ‐PFcEMA x ) with highly asymmetric weight fraction is synthesized in favor of the hydrophobic block ( x = 76–245). Of these, PEO 44 ‐ b ‐PFcEMA 96 assembled into PCs with an average particle diameter of 1.82 ± 0.48 µm, a double diamond lattice, and a pore diameter of ≈30–40 nm. The functionality of these PCs are showcased by i) templating metal oxide replica with concurrent decoration of magnetic iron oxide upon calcination, ii) supramolecular modification of the PC wall via host‐guest chemistry, and iii) degradation of the PC structure on demand through oxidation. Exploring these and other block chemistries enriches thetoolbox for PC applications and fosters theunderstanding about PCs by identifying differences or communalities in formation mechanisms and particle structure. 

Polyferrocene‐Based Cubosomes: Conversion to Magnetic Mesoporous Microparticles, Supramolecular Modification, and Oxidation Response

In this study, the interplay among the phospholipid 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) as a model membrane, the nonsteroidal anti-inflammatory drug naproxen, and the saponin β-aescin are investigated. The naproxen amount was fixed to 10 mol%, and the saponin amount varies from 0.0 to 1.0 mol%. Both substances are common ingredients in pharmaceutics; therefore, it is important to obtain deeper knowledge of their impact on lipid membranes. The size and properties of the DMPC model membrane upon naproxen and aescin addition were characterized with differential scanning calorimetry (DSC), small- and wide-angle X-ray scattering (SAXS, WAXS), and photon correlation spectroscopy (PCS) in a temperature-dependent study. The interaction of all substances was dependent on the lipid phase state, which itself depends on the lipid’s main phase transition temperature Tm. The incorporation of naproxen and aescin distorted the lipid membrane structure and lowers Tm. Below Tm, the DMPC–naproxen–aescin mixtures showed a vesicle structure, and the insertion of naproxen and aescin influenced neither the lipid chain–chain correlation distance nor the membrane thickness. Above Tm, the insertion of both molecules instead induced the formation of correlated bilayers and a decrease in the chain–chain correlation distance. The presented data clearly confirm the interaction of naproxen and aescin with DMPC model membranes. Moreover, the incorporation of both additives into the model membranes is evidenced.

/pdf/interactions-between-dmpc-model-membranes-the-drug-naproxen-s9263n2s.pdf

Interactions between DMPC Model Membranes, the Drug Naproxen, and the Saponin β-Aescin

Microplastic pollution and the urgent need for sustainable agriculture have raised interest in developing degradable carriers for controlled agrochemical release. Porous polymeric particles are particularly promising due to their unique release profiles compared to solid or core-shell carriers. However, creating degradable, mesoporous (2-50 nm) microparticles is challenging, and their potential for agrochemical delivery is largely unexplored. A straightforward self-assembly method is demonstrated for fully degradable porous polymer cubosomes (PCs), showcasing their ability to load and release agrochemicals. Using fully degradable block copolymers (BCPs), poly(ethyl ethylene phosphate)-b-polylactide (PEEP-b-PLA), PCs are synthesized in water with high inner order and open pores averaging 19 ± 3 nm in diameter. During the self-assembly process in the presence of the hydrophobic fungicide tebuconazole, polymersomes transform into PCs by enriching the hydrophobic polymer domain and altering the BCP packing parameter. After self-assemby, highly porous and fungicide-loaded PCs are obtained. Fungicide-loaded PCs show high antimycotic activity against Botrytis cinerea (grey mold), adhere to Vitis vinifera Riesling leaves even after simulated rain, and release the fungicide continuously over several days with different release-kinetics compared to solid particles. PCs hydrolyze completely into lactic acid and phosphate derivatives, highlighting their potential as microplastic-free agrochemical delivery systems for sustainable agriculture.

Fully Degradable Polyphosphoester Cubosomes for Sustainable Agrochemical Delivery.

In the present work, the temperature-dependent phase behavior of a C10E4 based microemulsion is studied in different meso–macroporous glasses, as a function of their pore diameter. The phase behavior in these pores is investigated by small-angle X-ray scattering (SAXS). The crucial parameter we discuss based on the SAXS results is the domain size of the bicontinuous phase. Using a simplified model to fit the scattering data, we can observe the microemulsion inside the pores. These experiments reveal a temperature-dependent change in domain sizes of the bicontinuous microemulsion only for large pores.

Confined microemulsions: pore diameter induced change of the phase behavior

Polymer cubosomes (PCs) are a recent class of self-assembled block copolymer (BCP) microparticles with an accessible periodic channel system. Most reported PCs consist of a polystyrene scaffold, which provides mechanical stability for templating but has a limited intrinsic functionality. Here, we report the synthesis of photocleavable BCPs with compositions suitable for PC formation. We analyze the self-assembly mechanism and study the model release of dyes during irradiation, where the transition of the BCPs from amphiphilic to bishydrophilic causes the rapid disassembly of the PCs. A combination of modeling and experiment shows that the evolution of PCs proceeds first via liquid-liquid phase separation into polymer-rich droplets, followed by microphase separation within this droplet confinement, and finally, membrane reorganization into high internal order. This insight may encourage exploration of alternative preparation strategies to better control the size and homogeneity of PCs.

Photocleavable Polymer Cubosomes: Synthesis, Self-Assembly, and Photorelease.

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Tim Julian Stank

Author Tools

Chat about Author

Papers

Interactions between DMPC Model Membranes, the Drug Naproxen, and the Saponin β-Aescin

Fully Degradable Polyphosphoester Cubosomes for Sustainable Agrochemical Delivery.

Confined microemulsions: pore diameter induced change of the phase behavior

Photocleavable Polymer Cubosomes: Synthesis, Self-Assembly, and Photorelease.