The development of metastasis is a leading cause of cancer-related death that involves specific changes in the plasma membrane (PM) and nucleus of cancer cells. Elevated levels of membrane lipids, including sphingomyelin, cholesterol, and phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), in the PM, contribute to changes in membrane rigidity, lipid raft formation, and actin polymerisation dynamics, processes that drive cell invasion. This review discusses the relationship between well-studied cytoplasmic phosphoinositides and their lesser-known nuclear counterparts, highlighting their functional role in metastatic progression. Nuclear phosphoinositides, particularly PI(4,5)P2, are essential for regulating transcription factors and chromatin organisation, thereby shaping gene expression patterns. We also explore the role of PI(4,5)P2 and its metabolism in cancer cell invasiveness and metastasis, proposing a model in which the dysregulation of cytosolic and/or nuclear PI(4,5)P2 pool triggers malignant transformation. Understanding the PI(4,5)P2-related mechanisms underlying metastasis may provide insights into potential therapeutic targets, paving the way for more effective therapies and improved patient outcomes.
- Klíčová slova
- Biocondensates, Cancer, HPV, Metastasis, Nucleus, Phosphatidylinositol 4,5-bisphosphate,
- MeSH
- buněčná membrána * metabolismus MeSH
- buněčné jádro * metabolismus MeSH
- fosfatidylinositol-4,5-difosfát * metabolismus MeSH
- lidé MeSH
- membránové mikrodomény metabolismus MeSH
- metastázy nádorů MeSH
- nádory * metabolismus patologie genetika MeSH
- signální transdukce * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- fosfatidylinositol-4,5-difosfát * MeSH
The endoplasmic reticulum is organized into ordered regions enriched in cholesterol and sphingomyelin, and disordered microdomains characterized by more fluidity. Rabbit CYP1A1 and CYP1A2 localize into disordered and ordered microdomains, respectively. Previously, a CYP1A2 chimera containing the first 109 amino acids of CYP1A1 showed altered microdomain localization. The goal of this study was to identify specific residues responsible for CYP1A microdomain localization. Thus, CYP1A2 chimeras containing substitutions from homologous regions of CYP1A1 were expressed in HEK 293T/17 cells, and the localization was examined after solubilization with Brij 98. A CYP1A2 mutant with the three amino acids from CYP1A1 (VAG) at positions 27 to 29 of CYP1A2 was generated that showed a distribution pattern similar to those of CYP1A1/1A2 chimeras containing both the first 109 amino acids and the first 31 amino acids of CYP1A1 followed by remaining amino acids of CYP1A2. Similarly, the reciprocal substitution of three amino acids from CYP1A2 (AVR) into CYP1A1 resulted in a partial redistribution of the chimera into ordered microdomains. Molecular dynamic simulations indicate that the positive charges of the CYP1A1 and CYP1A2 linker regions between the N termini and catalytic domains resulted in different depths of immersion of the N termini in the membrane. The overlap of the distribution of positively charged residues in CYP1A2 (AVR) and negatively charged phospholipids was higher in the ordered than in the disordered microdomain. These findings identify three residues in the CYP1AN terminus as a novel microdomain-targeting motif of the P450s and provide a mechanistic explanation for the differential microdomain localization of CYP1A.
- Klíčová slova
- CYP1A1, CYP1A2, cytochrome P450, membrane charge depth, membrane protein, microdomain localization, microdomain-targeting motif, protein chimera, protein-lipid interaction, structure-function,
- MeSH
- cytochrom P-450 CYP1A1 * genetika metabolismus chemie MeSH
- cytochrom P-450 CYP1A2 * metabolismus genetika chemie MeSH
- endoplazmatické retikulum metabolismus MeSH
- HEK293 buňky MeSH
- králíci MeSH
- lidé MeSH
- membránové mikrodomény metabolismus genetika MeSH
- proteinové domény MeSH
- sekvence aminokyselin MeSH
- simulace molekulární dynamiky MeSH
- substituce aminokyselin MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- cytochrom P-450 CYP1A1 * MeSH
- cytochrom P-450 CYP1A2 * MeSH
Biological membranes play a crucial role in actively hosting, modulating and coordinating a wide range of molecular events essential for cellular function. Membranes are organized into diverse domains giving rise to dynamic molecular patchworks. However, the very definition of membrane domains has been the subject of continuous debate. For example, in the plant field, membrane domains are often referred to as nanodomains, nanoclusters, microdomains, lipid rafts, membrane rafts, signalling platforms, foci or liquid-ordered membranes without any clear rationale. In the context of plant-microbe interactions, microdomains have sometimes been used to refer to the large area at the plant-microbe interface. Some of these terms have partially overlapping meanings at best, but they are often used interchangeably in the literature. This situation generates much confusion and limits conceptual progress. There is thus an urgent need for us as a scientific community to resolve these semantic and conceptual controversies by defining an unambiguous nomenclature of membrane domains. In this Review, experts in the field get together to provide explicit definitions of plasma membrane domains in plant systems and experimental guidelines for their study. We propose that plasma membrane domains should not be considered on the basis of their size alone but rather according to the biological system being considered, such as the local membrane environment or the entire cell.
The thermo- and pain-sensitive Transient Receptor Potential Melastatin 3 and 8 (TRPM3 and TRPM8) ion channels are functionally associated in the lipid rafts of the plasma membrane. We have already described that cholesterol and sphingomyelin depletion, or inhibition of sphingolipid biosynthesis decreased the TRPM8 but not the TRPM3 channel opening on cultured sensory neurons. We aimed to test the effects of lipid raft disruptors on channel activation on TRPM3- and TRPM8-expressing HEK293T cells in vitro, as well as their potential analgesic actions in TRPM3 and TRPM8 channel activation involving acute pain models in mice. CHO cell viability was examined after lipid raft disruptor treatments and their effects on channel activation on channel expressing HEK293T cells by measurement of cytoplasmic Ca2+ concentration were monitored. The effects of treatments were investigated in Pregnenolone-Sulphate-CIM-0216-evoked and icilin-induced acute nocifensive pain models in mice. Cholesterol depletion decreased CHO cell viability. Sphingomyelinase and methyl-beta-cyclodextrin reduced the duration of icilin-evoked nocifensive behavior, while lipid raft disruptors did not inhibit the activity of recombinant TRPM3 and TRPM8. We conclude that depletion of sphingomyelin or cholesterol from rafts can modulate the function of native TRPM8 receptors. Furthermore, sphingolipid cleavage provided superiority over cholesterol depletion, and this method can open novel possibilities in the management of different pain conditions.
- Klíčová slova
- Transient Receptor Potential, cholesterol, lipid raft, methyl-beta-cyclodextrin, pain, sphingomyelinase,
- MeSH
- analgetika farmakologie terapeutické užití MeSH
- beta-cyklodextriny * farmakologie MeSH
- bolest chemicky indukované farmakoterapie metabolismus MeSH
- CHO buňky MeSH
- cholesterol metabolismus MeSH
- Cricetulus MeSH
- HEK293 buňky MeSH
- kationtové kanály TRPM * metabolismus genetika MeSH
- lidé MeSH
- membránové mikrodomény metabolismus účinky léků MeSH
- modely nemocí na zvířatech MeSH
- myši MeSH
- pregnenolon farmakologie MeSH
- pyrimidinony farmakologie MeSH
- sfingomyelinfosfodiesterasa * metabolismus farmakologie MeSH
- viabilita buněk účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- analgetika MeSH
- beta-cyklodextriny * MeSH
- cholesterol MeSH
- icilin MeSH Prohlížeč
- kationtové kanály TRPM * MeSH
- methyl-beta-cyclodextrin MeSH Prohlížeč
- pregnenolon MeSH
- pregnenolone sulfate MeSH Prohlížeč
- pyrimidinony MeSH
- sfingomyelinfosfodiesterasa * MeSH
- TRPM3 protein, mouse MeSH Prohlížeč
- TRPM8 protein, mouse MeSH Prohlížeč
Styrene-maleic acid (SMA) and similar amphiphilic copolymers are known to cut biological membranes into lipid nanoparticles/nanodiscs containing membrane proteins apparently in their relatively native membrane lipid environment. Our previous work demonstrated that membrane raft microdomains resist such disintegration by SMA. The use of SMA in studying membrane proteins is limited by its heterogeneity and the inability to prepare defined derivatives. In the present paper, we demonstrate that some amphiphilic peptides structurally mimicking SMA also similarly disintegrate cell membranes. In contrast to the previously used copolymers, the simple peptides are structurally homogeneous. We found that their membrane-disintegrating activity increases with their length (reaching optimum at 24 amino acids) and requires a basic primary structure, that is, (XXD)n, where X represents a hydrophobic amino acid (optimally phenylalanine), D aspartic acid, and n is the number of repeats of these triplets. These peptides may provide opportunities for various well-defined potentially useful modifications in the study of membrane protein biochemistry. Our present results confirm a specific character of membrane raft microdomains.
- Klíčová slova
- leukocyte, lipid raft, lymphocyte, membrane, membrane proteins, peptides,
- MeSH
- buněčná membrána metabolismus chemie MeSH
- buněčné linie MeSH
- lidé MeSH
- maleáty chemie MeSH
- membránové mikrodomény metabolismus chemie MeSH
- membránové proteiny * chemie metabolismus MeSH
- peptidy * chemie MeSH
- polystyreny chemie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
An advantageous alternative to the use of detergents in biochemical studies on membrane proteins are the recently developed styrene-maleic acid (SMA) amphipathic copolymers. In our recent study [1] we demonstrated that using this approach, most T cell membrane proteins were fully solubilized (presumably in small nanodiscs), while two types of raft proteins, GPI-anchored proteins and Src family kinases, were mostly present in much larger (>250 nm) membrane fragments markedly enriched in typical raft lipids, cholesterol and lipids containing saturated fatty acid residues. In the present study we demonstrate that disintegration of membranes of several other cell types by means of SMA copolymer follows a similar pattern and we provide a detailed proteomic and lipidomic characterization of these SMA-resistant membrane fragments (SRMs).
- Klíčová slova
- Jurkat cell line, Lipidomics, Membrane rafts, Proteomics, SMA copolymer,
- MeSH
- buněčná membrána chemie MeSH
- maleáty analýza chemie MeSH
- mastné kyseliny analýza MeSH
- membránové mikrodomény MeSH
- membránové proteiny chemie MeSH
- polystyreny * chemie MeSH
- proteomika * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- maleáty MeSH
- maleic acid MeSH Prohlížeč
- mastné kyseliny MeSH
- membránové proteiny MeSH
- polystyreny * MeSH
- styrofoam MeSH Prohlížeč
Membrane cholesterol is essential for cell membrane properties, just as serum cholesterol is important for the transport of molecules between organs. This review focuses on cholesterol transport between lipoproteins and lipid rafts on the surface of macrophages. Recent studies exploring this mechanism and recognition of the central dogma-the key role of macrophages in cardiovascular disease-have led to the notion that this transport mechanism plays a major role in the pathogenesis of atherosclerosis. The exact molecular mechanism of this transport remains unclear. Future research will improve our understanding of the molecular and cellular bases of lipid raft-associated cholesterol transport.
- Klíčová slova
- cell membrane, cholesterol, macrophages,
- MeSH
- ateroskleróza * MeSH
- biologický transport MeSH
- buněčná membrána chemie metabolismus MeSH
- cholesterol chemie metabolismus MeSH
- homeostáza MeSH
- lidé MeSH
- lipoproteiny metabolismus MeSH
- makrofágy metabolismus MeSH
- membránové mikrodomény chemie metabolismus MeSH
- metabolismus lipidů MeSH
- vazba proteinů MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- cholesterol MeSH
- lipoproteiny MeSH
The respiratory pathogens Bordetella pertussis and Bordetella bronchiseptica employ a type III secretion system (T3SS) to inject a 69-kDa BteA effector protein into host cells. This effector is known to contain two functional domains, including an N-terminal lipid raft targeting (LRT) domain and a cytotoxic C-terminal domain that induces nonapoptotic and caspase-1-independent host cell death. However, the exact molecular mechanisms underlying the interaction of BteA with plasma membrane (PM) as well as its cytotoxic activity in the course of Bordetella infections remain poorly understood. Using a protein-lipid overlay assay and surface plasmon resonance, we show here that the recombinant LRT domain binds negatively charged membrane phospholipids. Specifically, we determined that the dissociation constants of the LRT domain-binding liposomes containing phosphatidylinositol 4,5-bisphosphate, phosphatidic acid, and phosphatidylserine were ∼450 nM, ∼490 nM, and ∼1.2 μM, respectively. Both phosphatidylserine and phosphatidylinositol 4,5-bisphosphate were required to target the LRT domain and/or full-length BteA to the PM of yeast cells. The membrane association further involved electrostatic and hydrophobic interactions of LRT and depended on a leucine residue in the L1 loop between the first two helices of the four-helix bundle. Importantly, charge-reversal substitutions within the L1 region disrupted PM localization of the BteA effector without hampering its cytotoxic activity during B. bronchiseptica infection of HeLa cells. The LRT-mediated targeting of BteA to the cytosolic leaflet of the PM of host cells is, therefore, dispensable for effector cytotoxicity.
- Klíčová slova
- Bordetella pertussis, BteA effector protein, Saccharomyces cerevisiae, lipid–protein interaction, membrane localization domain, plasma membrane, protein motif, surface plasmon resonance, type III secretion system, virulence factor,
- MeSH
- bakteriální proteiny genetika metabolismus MeSH
- Bordetella bronchiseptica genetika růst a vývoj metabolismus MeSH
- buněčná membrána metabolismus MeSH
- fosfolipidy metabolismus MeSH
- HeLa buňky MeSH
- lidé MeSH
- lipidové dvojvrstvy metabolismus MeSH
- membránové mikrodomény metabolismus MeSH
- proteinové domény MeSH
- vazba proteinů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- bakteriální proteiny MeSH
- fosfolipidy MeSH
- lipidové dvojvrstvy MeSH
T cells communicate with the environment via surface receptors. Cooperation of surface receptors regulates T-cell responses to diverse stimuli. Recently, finger-like membrane protrusions, microvilli, have been demonstrated to play a role in the organization of receptors and, hence, T-cell activation. However, little is known about the morphogenesis of dynamic microvilli, especially in the cells of immune system. In this review, I focus on the potential role of lipids and lipid domains in morphogenesis of microvilli. Discussed is the option that clustering of sphingolipids with phosphoinositides at the plasma membrane results in dimpling (curved) domains. Such domains can attract phosphoinositide-binding proteins and stimulate actin cytoskeleton reorganization. This process triggers cortical actin opening and bundling of actin fibres to support the growing of microvilli. Critical regulators of microvilli morphogenesis in T cells are unknown. At the end, I suggest several candidates with a potential to organize proteins and lipids in these structures.
- Klíčová slova
- T cell, dimpling domains, lipid rafts, membrane curvature, membrane-associated proteins, microvilli, phosphoinositides, sphingolipids,
- MeSH
- buněčná membrána chemie metabolismus MeSH
- fosfatidylinositoly metabolismus MeSH
- imunomodulace MeSH
- lidé MeSH
- membránové mikrodomény chemie metabolismus MeSH
- metabolismus lipidů * MeSH
- mikroklky metabolismus ultrastruktura MeSH
- morfogeneze MeSH
- sfingolipidy metabolismus MeSH
- signální transdukce MeSH
- T-lymfocyty cytologie fyziologie ultrastruktura MeSH
- vazba proteinů MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- fosfatidylinositoly MeSH
- sfingolipidy MeSH
Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a major cause of foodborne gastrointestinal illness. The adhesion of EHEC to host tissues is the first step enabling bacterial colonization. Adhesins such as fimbriae and flagella mediate this process. Here, we studied the interaction of the bacterial flagellum with the host cell's plasma membrane using giant unilamellar vesicles (GUVs) as a biologically relevant model. Cultured cell lines contain many different molecular components, including proteins and glycoproteins. In contrast, with GUVs, we can characterize the bacterial mode of interaction solely with a defined lipid part of the cell membrane. Bacterial adhesion on GUVs was dependent on the presence of the flagellar filament and its motility. By testing different phospholipid head groups, the nature of the fatty acid chains, or the liposome curvature, we found that lipid packing is a key parameter to enable bacterial adhesion. Using HT-29 cells grown in the presence of polyunsaturated fatty acid (α-linolenic acid) or saturated fatty acid (palmitic acid), we found that α-linolenic acid reduced adhesion of wild-type EHEC but not of a nonflagellated mutant. Finally, our results reveal that the presence of flagella is advantageous for the bacteria to bind to lipid rafts. We speculate that polyunsaturated fatty acids prevent flagellar adhesion on membrane bilayers and play a clear role for optimal host colonization. Flagellum-mediated adhesion to plasma membranes has broad implications for host-pathogen interactions.IMPORTANCE Bacterial adhesion is a crucial step to allow bacteria to colonize their hosts, invade tissues, and form biofilm. Enterohemorrhagic Escherichia coli O157:H7 is a human pathogen and the causative agent of diarrhea and hemorrhagic colitis. Here, we use biomimetic membrane models and cell lines to decipher the impact of lipid content of the plasma membrane on enterohemorrhagic E. coli flagellum-mediated adhesion. Our findings provide evidence that polyunsaturated fatty acid (α-linolenic acid) inhibits E. coli flagellar adhesion to the plasma membrane in a mechanism separate from its antimicrobial and anti-inflammatory functions. In addition, we confirm that cholesterol-enriched lipid microdomains, often called lipid rafts, are important in bacterial adhesion. These findings demonstrate that plasma membrane adhesion via bacterial flagella play a significant role for an important human pathogen. This mechanism represents a promising target for the development of novel antiadhesion therapies.
- Klíčová slova
- adhesins, flagella, lipid rafts, phospholipids,
- MeSH
- bakteriální adheze * MeSH
- buněčná membrána chemie MeSH
- buněčné linie MeSH
- buňky HT-29 MeSH
- epitelové buňky mikrobiologie MeSH
- Escherichia coli O157 fyziologie MeSH
- flagella metabolismus MeSH
- fosfolipidy analýza MeSH
- interakce hostitele a patogenu * MeSH
- kyselina alfa-linolenová analýza MeSH
- kyselina palmitová analýza MeSH
- lidé MeSH
- membránové mikrodomény chemie MeSH
- unilamelární lipozómy chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- fosfolipidy MeSH
- kyselina alfa-linolenová MeSH
- kyselina palmitová MeSH
- unilamelární lipozómy MeSH
