Neurodegenerative diseases are pathologies of the central and peripheral nervous systems characterized by loss of brain functions and problems in movement which occur due to the slow and progressive degeneration of cellular elements. Several neurodegenerative diseases are known such as Alzheimer's disease, Parkinson's disease and amyotrophic lateral sclerosis and many studies on the molecular mechanisms underlying these pathologies have been conducted. Altered functions of some key proteins and the presence of intraneuronal aggregates have been identified as responsible for the development of the diseases. Interestingly, the formation of the SNARE complex has been discovered to be fundamental for vesicle fusion, vesicle recycling and neurotransmitter release. Indeed, inhibition of the formation of the SNARE complex, defects in the SNARE-dependent exocytosis and altered regulation of SNARE-mediated vesicle fusion have been associated with neurodegeneration. In this review, the biological aspects of neurodegenerative diseases and the role of SNARE proteins in relation to the onset of these pathologies are described.

• MeSH
• exocytóza * MeSH
• fúze membrán * MeSH
• lidé MeSH
• nervový přenos * MeSH
• neurodegenerativní nemoci metabolismus   patofyziologie   MeSH
• proteiny SNARE metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

• Klíčová slova
• buněčné transportní váčky, intracelulární transportní mechanismy,
• MeSH
• fúze membrán MeSH
• intracelulární membrány MeSH
• lidé MeSH
• nervový přenos * fyziologie   MeSH
• Nobelova cena MeSH
• proteiny nervové tkáně MeSH
• proteiny R-SNARE MeSH
• proteiny SNARE * MeSH
• synapse fyziologie   MeSH
• synaptické membrány * MeSH
• významné osobnosti MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH

• O autorovi
• Rothman, James E.
• Schekman, Randy W.
• Südhof, Thomas C.

Specificity of membrane fusion in vesicular trafficking is dependent on proper subcellular distribution of soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs). Although SNARE complexes are fairly promiscuous in vitro, substantial specificity is achieved in cells owing to the spatial segregation and shielding of SNARE motifs prior to association with cognate Q-SNAREs. In this study, we identified phosphatidylinositol 4-kinase IIα (PI4K2A) as a binding partner of vesicle-associated membrane protein 3 (VAMP3), a small R-SNARE involved in recycling and retrograde transport, and found that the two proteins co-reside on tubulo-vesicular endosomes. PI4K2A knockdown inhibited VAMP3 trafficking to perinuclear membranes and impaired the rate of VAMP3-mediated recycling of the transferrin receptor. Moreover, depletion of PI4K2A significantly decreased association of VAMP3 with its cognate Q-SNARE Vti1a. Although binding of VAMP3 to PI4K2A did not require kinase activity, acute depletion of phosphatidylinositol 4-phosphate (PtdIns4P) on endosomes significantly delayed VAMP3 trafficking. Modulation of SNARE function by phospholipids had previously been proposed based on in vitro studies, and our study provides mechanistic evidence in support of these claims by identifying PI4K2A and PtdIns4P as regulators of an R-SNARE in intact cells.

• MeSH
• buněčná membrána metabolismus   MeSH
• Cercopithecus aethiops MeSH
• COS buňky MeSH
• endozomy metabolismus   MeSH
• fosfotransferasy s alkoholovou skupinou jako akceptorem metabolismus   MeSH
• fúze membrán fyziologie   MeSH
• lidé MeSH
• membránový protein 3 asociovaný s vezikuly metabolismus   MeSH
• proteiny SNARE metabolismus   MeSH
• receptory transferinu metabolismus   MeSH
• transport proteinů fyziologie   MeSH
• vezikulární transportní proteiny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Intramural MeSH

The exocyst complex, an effector of Rho and Rab GTPases, is believed to function as an exocytotic vesicle tether at the plasma membrane before soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex formation. Exocyst subunits localize to secretory-active regions of the plasma membrane, exemplified by the outer domain of Arabidopsis root epidermal cells. Using variable-angle epifluorescence microscopy, we visualized the dynamics of exocyst subunits at this domain. The subunits colocalized in defined foci at the plasma membrane, distinct from endocytic sites. Exocyst foci were independent of cytoskeleton, although prolonged actin disruption led to changes in exocyst localization. Exocyst foci partially overlapped with vesicles visualized by VAMP721 v-SNARE, but the majority of the foci represent sites without vesicles, as indicated by electron microscopy and drug treatments, supporting the concept of the exocyst functioning as a dynamic particle. We observed a decrease of SEC6-green fluorescent protein foci in an exo70A1 exocyst mutant. Finally, we documented decreased VAMP721 trafficking to the plasma membrane in exo70A1 and exo84b mutants. Our data support the concept that the exocyst-complex subunits dynamically dock and undock at the plasma membrane to create sites primed for vesicle tethering.

• MeSH
• Arabidopsis genetika   metabolismus   ultrastruktura   MeSH
• buněčná membrána metabolismus   ultrastruktura   MeSH
• cytoplazma metabolismus   ultrastruktura   MeSH
• cytoskelet metabolismus   ultrastruktura   MeSH
• epidermis rostlin genetika   metabolismus   ultrastruktura   MeSH
• exocytóza MeSH
• exprese genu MeSH
• fluorescenční mikroskopie MeSH
• kořeny rostlin genetika   metabolismus   ultrastruktura   MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• proteiny SNARE genetika   metabolismus   MeSH
• rab proteiny vázající GTP genetika   metabolismus   MeSH
• sekreční vezikuly metabolismus   ultrastruktura   MeSH
• transport proteinů MeSH
• vazba proteinů MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Plant phospholipase Ds (PLDs), essential regulators of phospholipid signaling, function in multiple signal transduction cascades; however, the mechanisms regulating PLDs in response to pathogens remain unclear. Here, we found that Arabidopsis (Arabidopsis thaliana) PLDδ accumulated in cells at the entry sites of the barley powdery mildew fungus, Blumeria graminis f. sp hordei Using fluorescence recovery after photobleaching and single-molecule analysis, we observed higher PLDδ density in the plasma membrane after chitin treatment; PLDδ also underwent rapid exocytosis. Fluorescence resonance energy transfer with fluorescence lifetime imaging microscopy showed that the interaction between PLDδ and the microdomain marker AtREMORIN1.3 (AtREM1.3) increased in response to chitin, indicating that exocytosis facilitates rapid, efficient sorting of PLDδ into microdomains upon pathogen stimulus. We further unveiled a trade-off between brefeldin A (BFA)-resistant and -sensitive pathways in secretion of PLDδ under diverse conditions. Upon pathogen attack, PLDδ secretion involved syntaxin-associated VAMP721/722-mediated exocytosis sensitive to BFA. Analysis of phosphatidic acid (PA), hydrogen peroxide, and jasmonic acid (JA) levels and expression of related genes indicated that the relocalization of PLDδ is crucial for its activation to produce PA and initiate reactive oxygen species and JA signaling pathways. Together, our findings revealed that the translocation of PLDδ to papillae is modulated by exocytosis, thus triggering PA-mediated signaling in plant innate immunity.plantcell;31/12/3015/FX1F1fx1.

• MeSH
• Arabidopsis genetika   imunologie   metabolismus   mikrobiologie   MeSH
• Ascomycota patogenita   MeSH
• brefeldin A imunologie   metabolismus   MeSH
• buněčná membrána metabolismus   MeSH
• chitin imunologie   metabolismus   MeSH
• cyklopentany metabolismus   MeSH
• exocytóza účinky léků   imunologie   MeSH
• fosfolipasa D genetika   metabolismus   MeSH
• kyseliny fosfatidové metabolismus   MeSH
• nemoci rostlin imunologie   mikrobiologie   MeSH
• oxylipiny metabolismus   MeSH
• peroxid vodíku metabolismus   MeSH
• přirozená imunita * účinky léků   MeSH
• proteiny huseníčku metabolismus   MeSH
• proteiny Qa-SNARE metabolismus   MeSH
• proteiny R-SNARE metabolismus   MeSH
• proteiny SNARE genetika   metabolismus   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• signální transdukce imunologie   fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Although phosphatidic acid (PA) is structurally the simplest membrane phospholipid, it has been implicated in the regulation of many cellular events, including cytoskeletal dynamics, membrane trafficking and stress responses. Plant PA shows rapid turnover but the information about its spatio-temporal distribution in plant cells is missing. Here we demonstrate the use of a lipid biosensor that enables us to monitor PA dynamics in plant cells. The biosensor consists of a PA-binding domain of yeast SNARE Spo20p fused to fluorescent proteins. Live-cell imaging of PA dynamics in transiently transformed tobacco (Nicotiana tabacum) pollen tubes was performed using confocal laser scanning microscopy. In growing pollen tubes, PA shows distinct annulus-like fluorescence pattern in the plasma membrane behind the extreme tip. Coexpression studies with markers for other plasmalemma signaling lipids phosphatidylinositol 4,5-bisphosphate and diacylglycerol revealed limited colocalization at the shoulders of the apex. PA distribution and concentrations show distinct responses to various lipid signaling inhibitors. Fluorescence recovery after photobleaching (FRAP) analysis suggests high PA turnover in the plasma membrane. Our data show that a biosensor based on the Spo20p-PA binding domain is suitable for live-cell imaging of PA also in plant cells. In tobacco pollen tubes, distinct subapical PA maximum corroborates its involvement in the regulation of endocytosis and actin dynamics.

• MeSH
• biosenzitivní techniky metody   MeSH
• buněčná membrána chemie   metabolismus   MeSH
• diglyceridy metabolismus   MeSH
• fluorescence MeSH
• fosfatidylinositol-4,5-difosfát metabolismus   MeSH
• fosfolipasa D metabolismus   MeSH
• fotovybělování MeSH
• kyseliny fosfatidové analýza   metabolismus   MeSH
• počítačové zpracování obrazu MeSH
• proteiny Qb-SNARE genetika   metabolismus   MeSH
• proteiny Qc-SNARE genetika   metabolismus   MeSH
• pylová láčka genetika   růst a vývoj   metabolismus   MeSH
• rekombinantní fúzní proteiny genetika   metabolismus   MeSH
• Saccharomyces cerevisiae - proteiny genetika   metabolismus   MeSH
• tabák cytologie   metabolismus   MeSH
• vazebná místa MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Extracellular vesicles are thought to facilitate pathogen transmission from arthropods to humans and other animals. Here, we reveal that pathogen spreading from arthropods to the mammalian host is multifaceted. Extracellular vesicles from Ixodes scapularis enable tick feeding and promote infection of the mildly virulent rickettsial agent Anaplasma phagocytophilum through the SNARE proteins Vamp33 and Synaptobrevin 2 and dendritic epidermal T cells. However, extracellular vesicles from the tick Dermacentor andersoni mitigate microbial spreading caused by the lethal pathogen Francisella tularensis. Collectively, we establish that tick extracellular vesicles foster distinct outcomes of bacterial infection and assist in vector feeding by acting on skin immunity. Thus, the biology of arthropods should be taken into consideration when developing strategies to control vector-borne diseases.

• MeSH
• Anaplasma phagocytophilum patogenita   MeSH
• bakteriální infekce imunologie   metabolismus   MeSH
• buněčné linie MeSH
• členovci metabolismus   mikrobiologie   fyziologie   MeSH
• Dermacentor metabolismus   mikrobiologie   fyziologie   MeSH
• extracelulární vezikuly metabolismus   ultrastruktura   MeSH
• Francisella tularensis patogenita   MeSH
• genová ontologie MeSH
• intravitální mikroskopie MeSH
• klíšťata metabolismus   mikrobiologie   MeSH
• klíště metabolismus   mikrobiologie   fyziologie   MeSH
• kůže imunologie   mikrobiologie   parazitologie   MeSH
• lidé MeSH
• membránový protein 2 asociovaný s vezikuly metabolismus   MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• myši MeSH
• proteiny R-SNARE metabolismus   MeSH
• proteomika MeSH
• T-lymfocyty metabolismus   MeSH
• tandemová hmotnostní spektrometrie MeSH
• transmisní elektronová mikroskopie MeSH
• zánět imunologie   metabolismus   parazitologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, N.I.H., Extramural MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

Auxin steers numerous physiological processes in plants, making the tight control of its endogenous levels and spatiotemporal distribution a necessity. This regulation is achieved by different mechanisms, including auxin biosynthesis, metabolic conversions, degradation, and transport. Here, we introduce cis-cinnamic acid (c-CA) as a novel and unique addition to a small group of endogenous molecules affecting in planta auxin concentrations. c-CA is the photo-isomerization product of the phenylpropanoid pathway intermediate trans-CA (t-CA). When grown on c-CA-containing medium, an evolutionary diverse set of plant species were shown to exhibit phenotypes characteristic for high auxin levels, including inhibition of primary root growth, induction of root hairs, and promotion of adventitious and lateral rooting. By molecular docking and receptor binding assays, we showed that c-CA itself is neither an auxin nor an anti-auxin, and auxin profiling data revealed that c-CA does not significantly interfere with auxin biosynthesis. Single cell-based auxin accumulation assays showed that c-CA, and not t-CA, is a potent inhibitor of auxin efflux. Auxin signaling reporters detected changes in spatiotemporal distribution of the auxin response along the root of c-CA-treated plants, and long-distance auxin transport assays showed no inhibition of rootward auxin transport. Overall, these results suggest that the phenotypes of c-CA-treated plants are the consequence of a local change in auxin accumulation, induced by the inhibition of auxin efflux. This work reveals a novel mechanism how plants may regulate auxin levels and adds a novel, naturally occurring molecule to the chemical toolbox for the studies of auxin homeostasis.

• MeSH
• Arabidopsis účinky léků   růst a vývoj   MeSH
• cinnamáty chemie   metabolismus   farmakologie   MeSH
• cyklin B genetika   metabolismus   MeSH
• geneticky modifikované rostliny MeSH
• isomerie MeSH
• kořeny rostlin účinky léků   růst a vývoj   metabolismus   MeSH
• kyseliny indoloctové metabolismus   MeSH
• mechy účinky léků   růst a vývoj   MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• proteiny Qa-SNARE genetika   metabolismus   MeSH
• regulace genové exprese u rostlin MeSH
• Selaginellaceae účinky léků   růst a vývoj   MeSH
• signální transdukce MeSH
• Publikační typ
• časopisecké články MeSH

Fosfatidylinositoly jsou významné signální molekuly, společně se SNARE proteiny hrají důležitou roli ve vesikulárním transportu. V tomto textu se snažíme zdůraznit vzájemnou součinnost SNARE proteinů a fosfatidylinositolových kinas. Vesikulární transport je velmi kom‐ plikovaný dynamický proces, který není doposud plně prostudován. Jeho pochopení může být klíčové pro léčbu závažných lidských nemocnění jako je například Gaucherova choroba, rakovina prsu, rakovina močového měchýře, papilární karcinom štítné žlázy a další.

Phosphatidylinositols ale important signal molecules, and together with SNARE proteins play important role in vesicular transport; a pro‐ cess that is still not fully understood. In this paper, we try to underline the interaction of SNARE proteins and phosphatidylinositol kinases. Vesicular transport is very complicated dynamic process. The understanding can be crucial for treatment of several human diseases such as Gaucher disease, breast cancer, bladder cancer, papillary thyroid carcinoma, and others.

• MeSH
• fosfatidylinositol-4-fosfát-3-kinasa fyziologie   MeSH
• fosfatidylinositoly * fyziologie   MeSH
• intracelulární prostor fyziologie   metabolismus   MeSH
• lidé MeSH
• vezikulární transportní proteiny * fyziologie   metabolismus   MeSH
• zdraví MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH

Synaptické váčky udržují recyklizací endocytózy a exocytózy pokračování normální synaptické transmise. SNARE komplex hraje centrální roli v Ca2+-vyvolaném výdeji neurotransmiteru. Dalším krokem je Clathrin- Dynamin-dependentní endocytóza.

The synaptic vesicles keep recycling by the processes of endocytosis and exocytosis to maintain the normal synaptic transmission. The SNARE complex plays a central role in Ca2+-triggered neurotransmitter release. The next step is Clathrin- Dynamindependent endocytosis.

• MeSH
• finanční podpora výzkumu jako téma MeSH
• neuroplasticita MeSH
• presynaptické terminály MeSH
• receptory presynaptické MeSH