Glutamate is the major excitatory neurotransmitter in the mammalian central nervous system. There are three distinct subtypes of ionotropic glutamate receptors (GluRs) that have been identified including 2-amino-3-(5-methyl-3-oxo-1,2-oxazol-4-yl)propanoic acid receptors (AMPARs), N-methyl-D-aspartate receptors (NMDARs) and kainate receptors. The most common GluRs in mature synapses are AMPARs that mediate the fast excitatory neurotransmission and NMDARs that mediate the slow excitatory neurotransmission. There have been large numbers of recent reports studying how a single neuron regulates synaptic numbers and types of AMPARs and NMDARs. Our current research is centered primarily on NMDARs and, therefore, we will focus in this review on recent knowledge of molecular mechanisms occurring (1) early in the biosynthetic pathway of NMDARs, (2) in the transport of NMDARs after their release from the endoplasmic reticulum (ER); and (3) at the plasma membrane including excitatory synapses. Because a growing body of evidence also indicates that abnormalities in NMDAR functioning are associated with a number of human psychiatric and neurological diseases, this review together with other chapters in this issue may help to enhance research and to gain further knowledge of normal synaptic physiology as well as of the etiology of many human brain diseases.

• Klíčová slova
• excitatory neurotransmission, glutamate receptor, internalization, intracellular trafficking, ion channel, subcellular compartment,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Neuronal voltage-gated calcium channels (VGCCs) serve complex yet essential physiological functions via their pivotal role in translating electrical signals into intracellular calcium elevations and associated downstream signalling pathways. There are a number of regulatory mechanisms to ensure a dynamic control of the number of channels embedded in the plasma membrane, whereas alteration of the surface expression of VGCCs has been linked to various disease conditions. Here, we provide an overview of the mechanisms that control the trafficking of VGCCs to and from the plasma membrane, and discuss their implication in pathophysiological conditions and their potential as therapeutic targets.

• Klíčová slova
• Stac adaptor proteins, ancillary subunit, calcium channels, glycosylation, trafficking, ubiquitination, voltage-gated calcium channels,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

The trafficking dynamics of uromodulin (UMOD), the most abundant protein in human urine, play a critical role in the pathogenesis of kidney disease. Monoallelic mutations in the UMOD gene cause autosomal dominant tubulointerstitial kidney disease (ADTKD-UMOD), an incurable genetic disorder that leads to kidney failure. The disease is caused by the intracellular entrapment of mutant UMOD in kidney epithelial cells, but the precise mechanisms mediating disrupted UMOD trafficking remain elusive. Here, we report that transmembrane Emp24 protein transport domain-containing (TMED) cargo receptors TMED2, TMED9, and TMED10 bind UMOD and regulate its trafficking along the secretory pathway. Pharmacological targeting of TMEDs in cells, in human kidney organoids derived from patients with ADTKD-UMOD, and in mutant-UMOD-knockin mice reduced intracellular accumulation of mutant UMOD and restored trafficking and localization of UMOD to the apical plasma membrane. In vivo, the TMED-targeted small molecule also mitigated ER stress and markers of kidney damage and fibrosis. Our work reveals TMED-targeting small molecules as a promising therapeutic strategy for kidney proteinopathies.

• Klíčová slova
• Genetic diseases, Nephrology, Protein misfolding, Protein traffic,
• MeSH
• lidé MeSH
• membránové glykoproteiny metabolismus   genetika   MeSH
• mutace MeSH
• myši MeSH
• transport proteinů * MeSH
• uromodulin * metabolismus   genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• membránové glykoproteiny MeSH
• UMOD protein, human MeSH Prohlížeč
• Umod protein, mouse MeSH Prohlížeč
• uromodulin * MeSH

This work is focused on the function of the microtubule and actin networks in plasmid DNA transport during liposomal transfection. We observed strong binding of plasmid DNA-lipid complexes (lipoplexes) to both networks and directional long-range motion of these lipoplexes along the microtubules. Disruption of either of these networks led to the cessation of plasmid transport to the nucleus, a decreased mobility of plasmids, and accumulation of plasmid DNA in large aggregates at the cell periphery. Our findings show an indispensable but different role of both types of cytoskeleton, actin and microtubular, in the processes of gene delivery.

• MeSH
• aktiny metabolismus   fyziologie   MeSH
• bicyklické sloučeniny heterocyklické farmakologie   MeSH
• biologický transport účinky léků   MeSH
• cytochalasin D farmakologie   MeSH
• DNA genetika   metabolismus   MeSH
• fibroblasty cytologie   účinky léků   metabolismus   MeSH
• imunoblotting MeSH
• kultivované buňky MeSH
• lidé MeSH
• mikrotubuly metabolismus   fyziologie   MeSH
• plazmidy genetika   metabolismus   MeSH
• rekombinantní fúzní proteiny genetika   metabolismus   MeSH
• thiazolidiny farmakologie   MeSH
• transfekce MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• aktiny MeSH
• bicyklické sloučeniny heterocyklické MeSH
• cytochalasin D MeSH
• DNA MeSH
• latrunculin B MeSH Prohlížeč
• rekombinantní fúzní proteiny MeSH
• thiazolidiny MeSH

BACKGROUND: Rab proteins are small monomeric enzymes which belong to the large Ras protein superfamily and allow hydrolysis of guanosine triphosphate (GTP) to guanosine (GDP). Up to now more than 60 proteins have been described that act primarily as regulators of intracellular transport. Rab GTPases are mostly located at the intracellular membranes, where they provide connections to motor proteins and to the cytoskeleton and control various steps of the traffic pathways including the formation and movement of vesicles or membrane fusion controlling secretion, endocytosis, recycling and degradation of proteins. Today, the deregulated expression of Rab protein is discussed in different types of malignancies. The number of identified diseases associated with mutations in Rab proteins or their cooperating partners increases and the evidence for the involvement of Rab to the human pathologies such as the immune failure, obesity and diabetes, Alzheimers disease or hereditary genetic diseases is growing. The malfunctions of Rab proteins caused by mutations or aberrant posttranslational modifications lead to changes in the protein and vesicle trafficking, which play a crucial role in the formation and development of cancer and the deregulation of Rab expression frequently influences the migration, invasion, proliferation and drug resistance of the tumor cells. AIMS: This article summarizes the main functions of Rab proteins in the cells, describes the mechanism of their activity and focuses on the current knowledge about the roles of these GTPases in carcinogenesis.Key words: Rab GTPases - protein transport - carcinogenesisThis work was supported by the project MEYS - NPS I - LO1413.The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 13. 5. 2016Accepted: 31. 5. 2016.

• MeSH
• intracelulární membrány metabolismus   MeSH
• lidé MeSH
• nádorová transformace buněk metabolismus   MeSH
• Rab proteiny vázající GTP genetika   metabolismus   MeSH
• transport proteinů * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• Rab proteiny vázající GTP MeSH

Ubiquitination is a versatile tool used by all eukaryotic organisms for controlling the stability, function, and intracellular localization of a wide variety of proteins. Two of the best characterized functions of protein ubiquitination are to mark proteins for degradation by cytosolic proteasome and to promote the internalization of certain plasma membrane proteins via the endocytotic pathway, followed by their degradation in the vacuole. Recent studies of membrane proteins both in yeast and mammalian cells suggest that the role of ubiquitin may extend beyond its function as an internalization signal in that it also may be required for modification of some component(s) of the endocytotic machinery, and for cargo protein sorting at the late endosome and the Golgi apparatus level. In this review, I will attempt to bring together what is currently known about the role of ubiquitination in controlling protein trafficking between the yeast plasma membrane, the trans-Golgi network, and the vacuole/lysosome.

• MeSH
• down regulace MeSH
• endocytóza MeSH
• endozomální třídící komplexy pro transport MeSH
• intracelulární membrány metabolismus   MeSH
• komplexy ubikvitinligas chemie   fyziologie   MeSH
• membránové proteiny metabolismus   MeSH
• Saccharomyces cerevisiae - proteiny chemie   fyziologie   MeSH
• Saccharomyces cerevisiae fyziologie   MeSH
• terciární struktura proteinů MeSH
• transport proteinů MeSH
• ubikvitin fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• endozomální třídící komplexy pro transport MeSH
• komplexy ubikvitinligas MeSH
• membránové proteiny MeSH
• RSP5 protein, S cerevisiae MeSH Prohlížeč
• Saccharomyces cerevisiae - proteiny MeSH
• ubikvitin MeSH

Small proteins represent a significant portion of the cargo transported through plant secretory pathways, playing crucial roles in developmental processes, fertilization, and responses to environmental stresses. Despite the importance of small secreted proteins, substantial knowledge gaps persist regarding the regulatory mechanisms governing their trafficking along the secretory pathway, and their ultimate localization or destination. To address these gaps, we conducted a comprehensive literature review, focusing particularly on trafficking and localization of Arabidopsis small secreted proteins with potential biochemical and/or signaling roles in the extracellular space, typically those within the size range of 101-200 amino acids. Our investigation reveals that while at least six members of the 21 mentioned families have a confirmed extracellular localization, eight exhibit intracellular localization, including cytoplasmic, nuclear, and chloroplastic locations, despite the presence of N-terminal signal peptides. Further investigation into the trafficking and secretion mechanisms of small protein cargo could not only deepen our understanding of plant cell biology and physiology but also provide a foundation for genetic manipulation strategies leading to more efficient plant cultivation.

• Klíčová slova
• Apoplast, Arabidopsis, exocytosis, peptides, secretion, signaling,
• MeSH
• Arabidopsis * metabolismus   genetika   MeSH
• proteiny huseníčku * metabolismus   genetika   MeSH
• sekreční dráha MeSH
• transport proteinů * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• proteiny huseníčku * MeSH

To compensate for their sessile lifestyle, plants developed several responses to exogenous changes. One of the previously investigated and not yet fully understood adaptations occurs at the level of early subcellular trafficking, which needs to be rapidly adjusted to maintain cellular homeostasis and membrane integrity under osmotic stress conditions. To form a vesicle, the membrane needs to be deformed, which is ensured by multiple factors, including the activity of specific membrane proteins, such as flippases from the family of P4-ATPases. The membrane pumps actively translocate phospholipids from the exoplasmic/luminal to the cytoplasmic membrane leaflet to generate curvature, which might be coupled with recruitment of proteins involved in vesicle formation at specific sites of the donor membrane. We show that lack of the AMINOPHOSPHOLIPID ATPASE3 (ALA3) flippase activity caused defects at the plasma membrane and trans-Golgi network, resulting in altered endocytosis and secretion, processes relying on vesicle formation and movement. The mentioned cellular defects were translated into decreased intracellular trafficking flexibility failing to adjust the root growth on osmotic stress-eliciting media. In conclusion, we show that ALA3 cooperates with ARF-GEF BIG5/BEN1 and ARF1A1C/BEX1 in a similar regulatory pathway to vesicle formation, and together they are important for plant adaptation to osmotic stress.

• Klíčová slova
• Arabidopsis thaliana, ARF, GEF, endocytosis, flippase, osmotic stress, protein trafficking, secretion,
• MeSH
• Arabidopsis * metabolismus   MeSH
• biologický transport MeSH
• buněčná membrána metabolismus   MeSH
• membránové proteiny metabolismus   MeSH
• osmotický tlak MeSH
• proteiny huseníčku * genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• membránové proteiny MeSH
• proteiny huseníčku * MeSH

Abiotic stress poses constant challenges for plant survival and is a serious problem for global agricultural productivity. On a molecular level, stress conditions result in elevation of reactive oxygen species (ROS) production causing oxidative stress associated with oxidation of proteins and nucleic acids as well as impairment of membrane functions. Adaptation of root growth to ROS accumulation is facilitated through modification of auxin and cytokinin hormone homeostasis. Here, we report that in Arabidopsis root meristem, ROS-induced changes of auxin levels correspond to decreased abundance of PIN auxin efflux carriers at the plasma membrane (PM). Specifically, increase in H2O2 levels affects PIN2 endocytic recycling. We show that the PIN2 intracellular trafficking during adaptation to oxidative stress requires the function of the ADP-ribosylation factor (ARF)-guanine-nucleotide exchange factor (GEF) BEN1, an actin-associated regulator of the trafficking from the PM to early endosomes and, presumably, indirectly, trafficking to the vacuoles. We propose that H2O2 levels affect the actin dynamics thus modulating ARF-GEF-dependent trafficking of PIN2. This mechanism provides a way how root growth acclimates to stress and adapts to a changing environment.

• Klíčová slova
• Adaptation, Auxin transport, Cytoskeleton, Hydrogen peroxide, Root apical meristem, Trafficking,
• MeSH
• ADP-ribosylační faktory metabolismus   fyziologie   MeSH
• aktiny metabolismus   MeSH
• alkoholoxidoreduktasy metabolismus   fyziologie   MeSH
• Arabidopsis metabolismus   fyziologie   MeSH
• cytoskelet metabolismus   MeSH
• fyziologická adaptace MeSH
• kořeny rostlin metabolismus   fyziologie   MeSH
• oxidační stres * MeSH
• peroxid vodíku metabolismus   MeSH
• proteiny huseníčku metabolismus   fyziologie   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• výměnné faktory guaninnukleotidů metabolismus   fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ADP-ribosylační faktory MeSH
• aktiny MeSH
• alkoholoxidoreduktasy MeSH
• BEN1 protein, Arabidopsis MeSH Prohlížeč
• peroxid vodíku MeSH
• PIN2 protein, Arabidopsis MeSH Prohlížeč
• proteiny huseníčku MeSH
• reaktivní formy kyslíku MeSH
• výměnné faktory guaninnukleotidů MeSH

In this work, levofloxacin (LVX), a third-generation fluoroquinolone antibiotic, is encapsulated within amphiphilic polymeric nanoparticles of a chitosan-g-poly(methyl methacrylate) produced by self-assembly and physically stabilized by ionotropic crosslinking with sodium tripolyphosphate. Non-crosslinked nanoparticles display a size of 29 nm and a zeta-potential of +36 mV, while the crosslinked counterparts display 45 nm and +24 mV, respectively. The cell compatibility, uptake, and intracellular trafficking are characterized in the murine alveolar macrophage cell line MH-S and the human bronchial epithelial cell line BEAS-2B in vitro. Internalization events are detected after 10 min and the uptake is inhibited by several endocytosis inhibitors, indicating the involvement of complex endocytic pathways. In addition, the nanoparticles are detected in the lysosomal compartment. Then, the antibacterial efficacy of LVX-loaded nanoformulations (50% w/w drug content) is assessed in MH-S and BEAS-2B cells infected with Staphylococcus aureus and the bacterial burden is decreased by 49% and 46%, respectively. In contrast, free LVX leads to a decrease of 8% and 5%, respectively, in the same infected cell lines. Finally, intravenous injection to a zebrafish larval model shows that the nanoparticles accumulate in macrophages and endothelium and demonstrate the promise of these amphiphilic nanoparticles to target intracellular infections.

• Klíčová slova
• amphiphilic chitosan nanoparticles, intracellular infections, levofloxacin, macrophages, nanomedicine,
• MeSH
• antibakteriální látky farmakologie   MeSH
• chitosan * MeSH
• dánio pruhované MeSH
• lidé MeSH
• makrofágy metabolismus   MeSH
• myši MeSH
• nanočástice * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antibakteriální látky MeSH
• chitosan * MeSH