Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| tcpho91 is a contractile vacuole phosphate sodium symporter that regulates phosphate and polyphosphate metabolism in trypanosoma cruzi. | we have identified a phosphate transporter (tcpho91) localized to the bladder of the contractile vacuole complex (cvc) of trypanosoma cruzi, the etiologic agent of chagas disease. tcpho91 has 12 transmembrane domains, an n-terminal regulatory spx (named after syg1, pho81 and xpr1) domain and an anion permease domain. functional expression in xenopus laevis oocytes followed by two-electrode voltage clamp showed that tcpho91 is a low-affinity transporter with a km for pi in the millimolar range, a ... | 2015 | 26031800 |
| investigation of blood flow and the effect of vasoactive substances in cutaneous blood vessels of xenopus laevis. | in the present study, a preparation of frog skin was presented, which can be used to demonstrate the basic concepts of blood flow regulation in a very clear and attractive way to high school and university students. in a freshly euthanized xenopus, a patch of abdominal skin was exposed from the internal side and viewed with a usb microscope while it remained connected to a functioning circulatory system. in this way, it was possible to obtain sharp images of arteries and veins and to visualize b ... | 2015 | 26031724 |
| proton-dependent glutamine uptake by aphid bacteriocyte amino acid transporter apglnt1. | aphids house large populations of the gammaproteobacterial symbiont buchnera aphidicola in specialized bacteriocyte cells. the combined biosynthetic capability of the holobiont (acyrthosiphon pisum and buchnera) is sufficient for biosynthesis of all twenty protein coding amino acids, including amino acids that animals alone cannot synthesize; and that are present at low concentrations in a. pisum's plant phloem sap diet. collaborative holobiont amino acid biosynthesis depends on glutamine import ... | 2015 | 26028424 |
| inhibition of monocarboxylate transporter by n-cyanosulphonamide s0859. | the synthetic compound n-cyanosulphonamide s0859 has been described as a selective inhibitor of sodium-bicarbonate cotransporters (nbc, slc4) in mammalian heart (ch'en et al., 2008). first, for comparison, the electrogenic human nbce1 (slc4a4) was heterologously expressed in xenopus laevis oocytes, where its transport activity was inhibited by s0859 with an ic50 of 9µm. the activity of monocarboxylate transporter (mct) isoforms 1, 2, and 4 (slc16a1, slc16a7, slc16a3), which transport lactate, py ... | 2015 | 26027796 |
| [comparative characteristics of free-living ultramicroscopical bacteria obtained from extremal biotopes]. | we isolated 50 strains of free-living ultrasmall bacteria with a cell volume that varies from 0.02 to 1.3 microm3 from a range of extremal natural biotopes, namely permafrost soils, oil slime, soils, lake silt, thermal swamp moss, and the skin integuments of the clawed frog, xenopus laevis. of them, 15 isolates, characterized by a cell size of less than 0.1 microm3 and a genome size from 1.5 to 2.4 mb, were subsumed to ultramicrobacteria belonging to different philogenetic groups (alphaproteobac ... | 2015 | 26027350 |
| desformylflustrabromine modulates α4β2 neuronal nicotinic acetylcholine receptor high- and low-sensitivity isoforms at allosteric clefts containing the β2 subunit. | alterations in expression patterns of α4β2 nicotinic acetylcholine receptors have been demonstrated to alter cholinergic neurotransmission and are implicated in neurologic disorders, including autism, nicotine addiction, alzheimer's disease, and parkinson's disease. positive allosteric modulators (pams) represent promising new leads in the development of therapeutic agents for the treatment of these disorders. this study investigates the involvement of the β2-containing subunit interfaces of α4β ... | 2015 | 26025967 |
| purification and characterization of cholecystokinin from the skin of salamander tylototriton verrucosus. | as a group of intestinal hormones and neurotransmitters, cholecystokinins (ccks) regulate and affect pancreatic enzyme secretion, gastrointestinal motility, pain hypersensitivity, digestion and satiety, and generally contain a dymgwmdfg sequence at the c-terminus. many ccks have been reported in mammals. however, only a few have been reported in amphibians, such as hyla nigrovittata, xenopus laevis, and rana catesbeiana, with none reported in urodele amphibians like newts and salamanders. here, ... | 2015 | 26018861 |
| anp and cnp activate cftr expressed in xenopus laevis oocytes by direct activation of pka. | acting through different receptors, natriuretic peptides (atrial natriuretic peptide [anp], brain type natriuretic peptide [bnp] and c-type natriuretic peptide [cnp]) increase intracellular cgmp, which then stimulates different pathways that activate fluid secretion. | 2015 | 26016495 |
| centrin-2 (cetn2) mediated regulation of fgf/fgfr gene expression in xenopus. | centrins (cetns) are highly conserved, widely expressed, and multifunctional ca(2+)-binding eukaryotic signature proteins best known for their roles in ciliogenesis and as critical components of the global genome nucleotide excision repair system. two distinct cetn subtypes, cetn2-like and cetn3-like, have been recognized and implicated in a range of cellular processes. in the course of morpholino-based loss of function studies in xenopus laevis, we have identified a previously unreported cetn2- ... | 2015 | 26014913 |
| xenopus tacc1 is a microtubule plus-end tracking protein that can regulate microtubule dynamics during embryonic development. | microtubule plus-end dynamics are regulated by a family of proteins called plus-end tracking proteins (+tips). we recently demonstrated that the transforming acidic coiled-coil (tacc) domain family member, tacc3, can function as a +tip to regulate microtubule dynamics in xenopus laevis embryonic cells. although it has been previously reported that tacc3 is the only tacc family member that exists in xenopus, our examination of its genome determined that xenopus, like all other vertebrates, contai ... | 2015 | 26012630 |
| bimodal interaction of mammalian polo-like kinase 1 and a centrosomal scaffold, cep192, in the regulation of bipolar spindle formation. | serving as microtubule-organizing centers, centrosomes play a key role in forming bipolar spindles. the mechanism of how centrosomes promote bipolar spindle assembly in various organisms remains largely unknown. a recent study with xenopus laevis egg extracts suggested that the plk1 ortholog plx1 interacts with the phospho-t46 (p-t46) motif of xenopus cep192 (xcep192) to form an xcep192-mediated xaura-plx1 cascade that is critical for bipolar spindle formation. here, we demonstrated that in cult ... | 2015 | 26012549 |
| paraxis is required for somite morphogenesis and differentiation in xenopus laevis. | in most vertebrates, the segmentation of the paraxial mesoderm involves the formation of metameric units called somites through a mesenchymal-epithelial transition. however, this process is different in xenopus laevis because it does not form an epithelial somite. xenopus somitogenesis is characterized by a complex cells rearrangement that requires the coordinated regulation of cell shape, adhesion, and motility. the molecular mechanisms that control these cell behaviors underlying somite format ... | 2015 | 26010523 |
| identification of distal enhancers for six2 expression in pronephros. | the embryonic nephric mesenchyme contains pluripotent progenitor cells. six2, a homeodomain transcription factor, is expressed in a subset of the nephric mesenchyme, and it functions to maintain a progenitor state by suppressing nephrogenesis. despite the functional significance of six2 in nephric development, its regulatory mechanisms remain unclear. to identify the cis-regulatory elements for six2, we focused on the evolutionarily conserved sequences known as conserved noncoding sequences (cns ... | 2015 | 26009236 |
| preparation of xenopus laevis retinal cryosections for electron microscopy. | transmission electron microscopy is the gold standard for examination of photoreceptor outer segment morphology and photoreceptor outer segment abnormalities in transgenic animal models of retinal disease. small vertebrates such as zebrafish and xenopus laevis tadpoles have been used to generate retinal disease models and to study outer segment processes such as protein trafficking, and their breeding capabilities facilitate experiments involving large numbers of animals and conditions. however, ... | 2015 | 26008144 |
| protein-carbohydrate interaction between sperm and the egg-coating envelope and its regulation by dicalcin, a xenopus laevis zona pellucida protein-associated protein. | protein-carbohydrate interaction regulates multiple important processes during fertilization, an essential biological event where individual gametes undergo intercellular recognition to fuse and generate a zygote. in the mammalian female reproductive tract, sperm temporarily adhere to the oviductal epithelium via the complementary interaction between carbohydrate-binding proteins on the sperm membrane and carbohydrates on the oviductal cells. after detachment from the oviductal epithelium at the ... | 2015 | 26007194 |
| passive stiffness of hindlimb muscles in anurans with distinct locomotor specializations. | anurans (frogs and toads) have been shown to have relatively compliant skeletal muscles. using a meta-analysis of published data we have found that muscle stiffness is negatively correlated with joint range of motion when examined across mammalian, anuran and bird species. given this trend across a broad phylogenetic sample, we examined whether the relationship held true within anurans. we identified four species that differ in preferred locomotor mode and hence joint range of motion (lithobates ... | 2015 | 26006308 |
| dynein-based accumulation of membranes regulates nuclear expansion in xenopus laevis egg extracts. | nuclear size changes dynamically during development and has long been observed to correlate with the space surrounding the nucleus, as well as with the volume of the cell. here we combine an in vitro cell-free system of xenopus laevis egg extract with microfluidic devices to systematically analyze the effect of spatial constraints. the speed of nuclear expansion depended on the available space surrounding the nucleus up to a threshold volume in the nanoliter range, herein referred to as the nucl ... | 2015 | 26004509 |
| formation of a new limb bud at the boundary between a transplanted limb bud and the tail surface of xenopus tadpoles. | through transplantation experiments with xenopus laevis tadpoles, we found a new morphogenetic phenomenon consisting of limb bud formation at the boundary between transplanted whole limb buds and the tail surface. this phenomenon occurs without limb-limb stump interaction and has a number of unique features: (1) only one extra limb bud was formed per transplant and the new limb and the transplanted limb were bilaterally symmetrical, forming a pair of limb girdles. (2) extra new limb bud formatio ... | 2015 | 26003976 |
| using supported bilayers to study the spatiotemporal organization of membrane-bound proteins. | cell division in prokaryotes and eukaryotes is commonly initiated by the well-controlled binding of proteins to the cytoplasmic side of the cell membrane. however, a precise characterization of the spatiotemporal dynamics of membrane-bound proteins is often difficult to achieve in vivo. here, we present protocols for the use of supported lipid bilayers to rebuild the cytokinetic machineries of cells with greatly different dimensions: the bacterium escherichia coli and eggs of the vertebrate xeno ... | 2015 | 25997350 |
| characterization of the target of ivermectin, the glutamate-gated chloride channel, from anopheles gambiae. | the use of insecticide-treated nets and indoor residual insecticides targeting adult mosquito vectors is a key element in malaria control programs. however, mosquito resistance to the insecticides used in these applications threatens malaria control efforts. recently, the mass drug administration of ivermectin (ivm) has been shown to kill anopheles gambiae mosquitoes and disrupt plasmodium falciparum transmission in the field. we cloned the molecular target of ivm from a. gambiae, the glutamate- ... | 0 | 25994631 |
| asymmetrical allocation of jak1 mrna during spermatogonial stem cell division in xenopus laevis. | during xenopus spermatogenesis, each primary spermatogonium (pg), the largest single cell in the testis, undergoes mitotic divisions with a concomitant decrease in size to produce smaller differentiating spermatogonia. the spermatogonial stem cells (sscs) occur in this pg population. taking advantage of identifiable and isolatable properties of xenopus sscs, we examined jak1 gene expression during the spermatogenesis because there have been reports on the important role of jak/stat pathway in re ... | 2015 | 25988600 |
| in vitro and in vivo evidence for active brain uptake of the ghb analog hocpca by the monocarboxylate transporter subtype 1. | γ-hydroxybutyric acid (ghb) is a recreational drug, a clinically prescribed drug in narcolepsy and alcohol dependence, and an endogenous substance that binds to both high- and low-affinity sites in the brain. for studying the molecular mechanisms and the biologic role of the ghb high-affinity binding sites, ligands with high and specific affinity are essential. the conformationally restricted ghb analog hocpca (3-hydroxycyclopent-1-enecarboxylic acid) is one such compound. the objective of this ... | 2015 | 25986445 |
| expressing and characterizing mechanosensitive channels in xenopus oocytes. | the oocytes of the african clawed frog (xenopus laevis) comprise one of the most widely used membrane protein expression systems. while frequently used for studies of transporters and ion channels, the application of this system to the study of mechanosensitive ion channels has been overlooked, perhaps due to a relative abundance of native expression systems. recent advances, however, have illustrated the advantages of the oocyte system for studying plant and bacterial mechanosensitive channels. ... | 2015 | 25981775 |
| ethanol modulation is quantitatively determined by the transmembrane domain of human α1 glycine receptors. | mutagenesis and labeling studies have identified amino acids from the human α1 glycine receptor (glyr) extracellular, transmembrane (tm), and intracellular domains in mediating ethanol (etoh) potentiation. however, limited high-resolution structural data for physiologically relevant receptors in this cys-loop receptor superfamily have made pinpointing the critical amino acids difficult. homologous ion channels from lower organisms provide conserved models for structural and functional properties ... | 2015 | 25973519 |
| labeling strategy and signal broadening mechanism of protein nmr spectroscopy in xenopus laevis oocytes. | we used xenopus laevis oocytes, a paradigm for a variety of biological studies, as a eukaryotic model system for in-cell protein nmr spectroscopy. the small globular protein gb1 was one of the first studied in xenopus oocytes, but there have been few reports since then of high-resolution spectra in oocytes. the scarcity of data is at least partly due to the lack of good labeling strategies and the paucity of information on resonance broadening mechanisms. here, we systematically evaluate isotope ... | 2015 | 25965532 |
| conformational rearrangements in the transmembrane domain of cnga1 channels revealed by single-molecule force spectroscopy. | cyclic nucleotide-gated (cng) channels are activated by binding of cyclic nucleotides. although structural studies have identified the channel pore and selectivity filter, conformation changes associated with gating remain poorly understood. here we combine single-molecule force spectroscopy (smfs) with mutagenesis, bioinformatics and electrophysiology to study conformational changes associated with gating. by expressing functional channels with smfs fingerprints in xenopus laevis oocytes, we we ... | 2015 | 25963832 |
| positive modulation of synaptic and extrasynaptic gabaa receptors by an antagonist of the high affinity benzodiazepine binding site. | gabaa receptors are the major inhibitory neurotransmitter receptors in the brain and are the target for many clinically important drugs such as the benzodiazepines. benzodiazepines act at the high-affinity binding site at the α+/γ- subunit interface. previously, an additional low affinity binding site for diazepam located in the transmembrane (tm) domain has been described. the compound sjm-3 was recently identified in a prospective screening of ligands for the benzodiazepine binding site and in ... | 2015 | 25963418 |
| xenopus laevis oocyte maturation is affected by metal chlorides. | few studies have been conducted using xenopus laevis germ cells as oocytes, though these cells offer many advantages allowing both electrophysiological studies and morphological examination. our aim was to investigate the effects of metal (cadmium, lead, cobalt and zinc) exposures using cell biology approaches. first, cell survival was evaluated with both phenotypical and electrophysiological approaches. secondly, the effect of metals on oocyte maturation was assessed with morphological observat ... | 2015 | 25957907 |
| building the microtubule cytoskeleton piece by piece. | the microtubule (mt) cytoskeleton gives cells their shape, organizes the cellular interior, and segregates chromosomes. these functions rely on the precise arrangement of mts, which is achieved by the coordinated action of mt-associated proteins (maps). we highlight the first and most important examples of how different map activities are combined in vitro to create an ensemble function that exceeds the simple addition of their individual activities, and how the xenopus laevis egg extract system ... | 2015 | 25957410 |
| in vitro, ex vivo, and in vivo determination of thyroid hormone modulating activity of benzothiazoles. | as in vitro assays are increasingly used to screen chemicals for their potential to produce endocrine disrupting adverse effects, it is important to understand their predictive capacity. the potential for a set of 6 benzothiazoles to affect endpoints related to thyroid hormone synthesis inhibition were assessed using in vitro, ex vivo, and in vivo assays. inhibition of thyroid peroxidase (tpo) derived from pig thyroid glands was determined for benzothiazole (btz), 2-mercaptobenzothiazole (mbt), ... | 2015 | 25953703 |
| effects of an environmentally relevant temporal application scheme of low herbicide concentrations on larvae of two anuran species. | cultivation of herbicide-tolerant crops involves repeated applications of the complementary herbicide throughout the growing season, while in conventional corn production, herbicide application is restricted to the beginning of cultivation. repeated application of herbicides increases both the likelihood an organism will be exposed to the herbicide and the concentration it may be exposed to. we examined effects of short and pulsed exposure of the cycloxydim-based herbicide formulation focus® ult ... | 2015 | 25950411 |
| subchronic and chronic developmental effects of copper oxide (cuo) nanoparticles on xenopus laevis. | metal oxide nanoparticles, such as copper oxide (cuo), are mass produced for use in a variety of products like coatings and ceramics. acute exposure to cuo nanoparticles has caused toxicity to many aquatic organisms, yet there is no information on the effect of prolonged cuo nanomaterial exposures. this study examined effects of chronic exposure to cuo nanoparticles on xenopus laevis growth and development. experiments included a 14 d subchronic exposure and a 47 d chronic exposure throughout me ... | 2015 | 25950410 |
| mgcracgap restricts active rhoa at the cytokinetic furrow and both rhoa and rac1 at cell-cell junctions in epithelial cells. | localized activation of rho gtpases is essential for multiple cellular functions, including cytokinesis and formation and maintenance of cell-cell junctions. although mgcracgap (mgc) is required for spatially confined rhoa-gtp at the equatorial cortex of dividing cells, both the target specificity of mgc's gap activity and the involvement of phosphorylation of mgc at ser-386 are controversial. in addition, mgc's function at cell-cell junctions remains unclear. here, using gastrula-stage xenopus ... | 2015 | 25947135 |
| structural insights into thyroid hormone transport mechanisms of the l-type amino acid transporter 2. | thyroid hormones (ths) are transported across cell membranes by different transmembrane transporter proteins. in previous studies, we showed marked 3,3'-diiodothyronine (3,3'-t2) but moderate t3 uptake by the l-type amino acid transporter 2 (lat2). we have now studied the structure-function relationships of this transporter and th-like molecules. our lat2 homology model is based on 2 crystal structures of the homologous 12-transmembrane helix transporters arginine/agmatine antiporter and amino a ... | 2015 | 25945809 |
| single-cell mass spectrometry reveals small molecules that affect cell fates in the 16-cell embryo. | spatial and temporal changes in molecular expression are essential to embryonic development, and their characterization is critical to understand mechanisms by which cells acquire different phenotypes. although technological advances have made it possible to quantify expression of large molecules during embryogenesis, little information is available on metabolites, the ultimate indicator of physiological activity of the cell. here, we demonstrate that single-cell capillary electrophoresis-electr ... | 2015 | 25941375 |
| epigenetic regulation of thyroid hormone-induced adult intestinal stem cell development during anuran metamorphosis. | epigenetic modifications of histones are emerging as key factors in gene regulation by diverse transcription factors. their roles during vertebrate development and pathogenesis are less clear. the causative effect of thyroid hormone (t3) on amphibian metamorphosis and the ability to manipulate this process for molecular and genetic studies have led to the demonstration that t3 receptor (tr) is necessary and sufficient for xenopus metamorphosis, a process that resembles the postembryonic developm ... | 2014 | 25937894 |
| controlled surface topography regulates collective 3d migration by epithelial-mesenchymal composite embryonic tissues. | cells in tissues encounter a range of physical cues as they migrate. probing single cell and collective migratory responses to physically defined three-dimensional (3d) microenvironments and the factors that modulate those responses are critical to understanding how tissue migration is regulated during development, regeneration, and cancer. one key physical factor that regulates cell migration is topography. most studies on surface topography and cell mechanics have been carried out with single ... | 2015 | 25933063 |
| follicle online: an integrated database of follicle assembly, development and ovulation. | folliculogenesis is an important part of ovarian function as it provides the oocytes for female reproductive life. characterizing genes/proteins involved in folliculogenesis is fundamental for understanding the mechanisms associated with this biological function and to cure the diseases associated with folliculogenesis. a large number of genes/proteins associated with folliculogenesis have been identified from different species. however, no dedicated public resource is currently available for fo ... | 2015 | 25931457 |
| regulation of hbpip2;3, a latex-abundant water transporter, is associated with latex dilution and yield in the rubber tree (hevea brasiliensis muell. arg.). | rubber tree (hevea brasiliensis) latex, the source of natural rubber, is synthesised in the cytoplasm of laticifers. efficient water inflow into laticifers is crucial for latex flow and production since it is the determinant of the total solid content of latex and its fluidity after tapping. as the mature laticifer vessel rings are devoid of plasmodesmata, water exchange between laticifers and surrounding cells is believed to be governed by plasma membrane intrinsic proteins (pips). to identify ... | 2015 | 25927524 |
| quantum dot assisted tracking of the intracellular protein cyclin e in xenopus laevis embryos. | luminescent semiconductor nanocrystals, also known as quantum dots (qd), possess highly desirable optical properties that account for development of a variety of exciting biomedical techniques. these properties include long-term stability, brightness, narrow emission spectra, size tunable properties and resistance to photobleaching. qd have many promising applications in biology and the list is constantly growing. these applications include dna or protein tagging for in vitro assays, deep-tissue ... | 2015 | 25925383 |
| the xenopus laevis atg4b protease: insights into substrate recognition and application for tag removal from proteins expressed in pro- and eukaryotic hosts. | during autophagy, members of the ubiquitin-like atg8 protein family get conjugated to phosphatidylethanolamine and act as protein-recruiting scaffolds on the autophagosomal membrane. the atg4 protease produces mature atg8 from c-terminally extended precursors and deconjugates lipid-bound atg8. we now found that xenopus laevis atg4b (xatg4b) is ideally suited for proteolytic removal of n-terminal tags from recombinant proteins. to implement this strategy, an atg8 cleavage module is inserted in be ... | 2015 | 25923686 |
| disruption of the rice nitrate transporter osnpf2.2 hinders root-to-shoot nitrate transport and vascular development. | plants have evolved to express some members of the nitrate transporter 1/peptide transporter family (npf) to uptake and transport nitrate. however, little is known of the physiological and functional roles of this family in rice (oryza sativa l.). here, we characterized the vascular specific transporter osnpf2.2. functional analysis using cdna-injected xenopus laevis oocytes revealed that osnpf2.2 is a low-affinity, ph-dependent nitrate transporter. use of a green fluorescent protein tagged osnp ... | 2015 | 25923512 |
| hplc-based activity profiling for herg channel inhibitors in the south african medicinal plant galenia africana. | the human ether-a-go-go-related gene channel is a voltage-activated k(+) channel involved in cardiac action potential. its inhibition can lead to qt prolongation, and eventually to potentially fatal arrhythmia. therefore, it is considered a primary antitarget in safety pharmacology. to assess the risk of human ether-a-go-go-related gene channel inhibition by medicinal plants, 700 extracts from different parts of 142 medicinal plants collected in southern africa were screened on xenopus laevis oo ... | 2015 | 25922911 |
| homeolog-specific targeted mutagenesis in xenopus laevis using talens. | transcription activator-like effector nucleases (talens) have previously been used for targeted genome editing in various organisms including xenopus laevis. however, because of genomic polyploidization, x. laevis usually possess homeologous genes (homeologs) with quite similar sequences that make the analysis of gene function difficult. in the present study, we show methodological examples of targeted gene modification of x. laevis homeologs. the x. laevis cytoglobin gene (cygb) consists of two ... | 2015 | 25920501 |
| involvement of histidine residue his382 in ph regulation of mct4 activity. | monocarboxylate transporter 4 (mct4) is a ph-dependent bi-directional lactate transporter. transport of lactate via mct4 is increased by extracellular acidification. we investigated the critical histidine residue involved in ph regulation of mct4 function. transport of lactate via mct4 was measured by using a xenopus laevis oocyte expression system. mct4-mediated lactate transport was inhibited by zn2+ in a ph physiological condition but not in an acidic condition. the histidine modifier depc (d ... | 2014 | 25919709 |
| deconstructing cartilage shape and size into contributions from embryogenesis, metamorphosis, and tadpole and frog growth. | understanding skeletal diversification involves knowing not only how skeletal rudiments are shaped embryonically, but also how skeletal shape changes throughout life. the pharyngeal arch (pa) skeleton of metamorphosing amphibians persists largely as cartilage and undergoes two phases of development (embryogenesis and metamorphosis) and two phases of growth (larval and post-metamorphic). though embryogenesis and metamorphosis produce species-specific features of pa cartilage shape, the extents to ... | 2015 | 25913729 |
| urotensin ii upregulates migration and cytokine gene expression in leukocytes of the african clawed frog, xenopus laevis. | urotensin ii (uii) exhibits diverse physiological actions including vasoconstriction, locomotor activity, osmoregulation, and immune response via the uii receptor (utr) in mammals. however, in amphibians the function of the uii-utr system remains unknown. in the present study, we investigated the potential immune function of uii using leukocytes isolated from the african clawed frog, xenopus laevis. stimulation of male frogs with lipopolysaccharide increased mrna expression of uii and utr in leu ... | 2015 | 25907658 |
| transport function of rice amino acid permeases (aaps). | the transport function of four rice (oryza sativa) amino acid permeases (aaps), osaap1 (os07g04180), osaap3 (os06g36180), osaap7 (os05g34980) and osaap16 (os12g08090), was analyzed by expression in xenopus laevis oocytes and electrophysiology. osaap1, osaap7 and osaap16 functioned, similarly to arabidopsis aaps, as general amino acid permeases. osaap3 had a distinct substrate specificity compared with other rice or arabidopsis aaps. osaap3 transported the basic amino acids lysine and arginine we ... | 2015 | 25907566 |
| influence of hydrophobic residues on the activity of the antimicrobial peptide magainin 2 and its synergy with pgla. | magainin 2 (mag2) and pgla are two related antimicrobial peptides found in the skin of the african frog xenopus laevis with a pronounced synergistic activity, which act by permeabilizing bacterial membranes. to probe the influence of hydrophobic peptide-lipid and peptide-peptide interactions on the antimicrobial activity and on synergy, the sequence of mag2 was modified by replacing single amino acids either with a small alanine or with the stiff and bulky hydrophobic 3-(trifluoromethyl)-l-bicyc ... | 2015 | 25898805 |
| the influence of artificially introduced n-glycosylation sites on the in vitro activity of xenopus laevis erythropoietin. | erythropoietin (epo), the primary regulator of erythropoiesis, is a heavily glycosylated protein found in humans and several other mammals. intriguingly, we have previously found that epo in xenopus laevis (xlepo) has no n-glycosylation sites, and cross-reacts with the human epo (huepo) receptor despite low homology with huepo. in this study, we introduced n-glycosylation sites into wild-type xlepo at the positions homologous to those in huepo, and tested whether the glycosylated mutein retained ... | 2015 | 25898205 |
| targeted gene disruption in xenopus laevis using crispr/cas9. | 2015 | 25897376 | |
| glutamylation of nap1 modulates histone h1 dynamics and chromosome condensation in xenopus. | linker histone h1 is required for mitotic chromosome architecture in xenopus laevis egg extracts and, unlike core histones, exhibits rapid turnover on chromatin. mechanisms regulating the recruitment, deposition, and dynamics of linker histones in mitosis are largely unknown. we found that the cytoplasmic histone chaperone nucleosome assembly protein 1 (nap1) associates with the embryonic isoform of linker histone h1 (h1m) in egg extracts. immunodepletion of nap1 decreased h1m binding to mitotic ... | 2015 | 25897082 |
| left-right patterning in xenopus conjoined twin embryos requires serotonin signaling and gap junctions. | a number of processes operating during the first cell cleavages enable the left-right (lr) axis to be consistently oriented during xenopus laevis development. prior work showed that secondary organizers induced in frog embryos after cleavage stages (i.e. conjoined twins arising from ectopic induced primary axes) correctly pattern their own lr axis only when a primary (early) organizer is also present. this instructive effect confirms the unique lr patterning functions that occur during early emb ... | 2014 | 25896280 |
| optogenetics in developmental biology: using light to control ion flux-dependent signals in xenopus embryos. | developmental bioelectricity, electrical signaling among non-excitable cells, is now known to regulate proliferation, apoptosis, gene expression, and patterning during development. the extraordinary temporal and spatial resolution offered by optogenetics could revolutionize the study of bioelectricity the same way it has revolutionized neuroscience. there is, however, no guide to adapting optogenetics to patterning systems. to fill this gap, we used optogenetic reagents, both proteins and photoc ... | 2014 | 25896279 |
| remyelination by resident oligodendrocyte precursor cells in a xenopus laevis inducible model of demyelination. | we have generated a xenopus laevis transgenic line, mbp-gfp-ntr, allowing conditional ablation of myelin-forming oligodendrocytes. in this transgenic line the transgene is driven by the proximal portion of the myelin basic protein regulatory sequence, specific to mature oligodendrocytes. the transgene protein is formed by the green fluorescent protein reporter fused to the escherichia coli nitroreductase (ntr) selection enzyme. the ntr enzyme converts the innocuous prodrug metronidazole (mtz) to ... | 2015 | 25896276 |
| developmental expression of pitx2c in xenopus trigeminal and profundal placodes. | cranial placodes are thickenings of the embryonic head ectoderm that contribute to the paired sense organs and to the cephalic peripheral nervous system. here we report the spatiotemporal expression pattern of transcription factor pitx2c during xenopus laevis cranial placode formation, focusing more specifically on key stages of trigeminal and profundal placode development. we also compare its expression to five genes that have been associated with development of these sensory placodes, namely f ... | 2014 | 25896206 |
| notch is a direct negative regulator of the dna-damage response. | the dna-damage response (ddr) ensures genome stability and proper inheritance of genetic information, both of which are essential to survival. it is presently unclear to what extent other signaling pathways modulate ddr function. here we show that notch receptor binds and inactivates atm kinase and that this mechanism is evolutionarily conserved in caenorhabditis elegans, xenopus laevis and humans. in c. elegans, the notch pathway impairs ddr signaling in gonad germ cells. in mammalian cells, ac ... | 2015 | 25895060 |
| iron deficiency regulated osopt7 is essential for iron homeostasis in rice. | the molecular mechanism of iron (fe) uptake and transport in plants are well-characterized; however, many components of fe homeostasis remain unclear. we cloned iron-deficiency-regulated oligopeptide transporter 7 (osopt7) from rice. osopt7 localized to the plasma membrane and did not transport fe(iii)-dma or fe(ii)-na and gsh in xenopus laevis oocytes. furthermore osopt7 did not complement the growth of yeast fet3fet4 mutant. osopt7 was specifically upregulated in response to fe-deficiency. pro ... | 2015 | 25893776 |
| gene expression profiles in rana pirica tadpoles following exposure to a predation threat. | rana pirica tadpoles show morphological changes in response to a predation threat: larvae of the dragonfly aeshna nigroflava induce heightened tail depth, whereas larval salamander hynobius retardatus induce a bulgy morphology with heightened tail depth. although both predators induce similar tail morphologies, it is possible that there are functional differences between these tail morphs. | 2015 | 25886855 |
| identification and expression of an atypical isoform of metallothionein in the african clawed frog xenopus laevis. | exploiting the annotation of the western clawed frog silurana tropicalis genome, we identified a new metallothionein (mt) gene, exhibiting all the features to be considered an active gene, but with an atypical coding region, showing only 17 cysteine residues instead of the canonical 20 cysteines of vertebrate metallothioneins and two anomalous cysteine triplets. however, the presence of a gene in the genome does not ensure its effective expression. by using conventional and real-time pcr analyse ... | 2015 | 25882350 |
| impact of maternal n-3 polyunsaturated fatty acid deficiency on dendritic arbor morphology and connectivity of developing xenopus laevis central neurons in vivo. | docosahexaenoic acid (dha, 22:6n-3) is an essential component of the nervous system, and maternal n-3 polyunsaturated fatty acids (pufas) are an important source for brain development. here, the impact of dha on developing central neurons was examined using an accessible in vivo model. xenopus laevis embryos from adult female frogs fed n-3 pufa-adequate or deficient diets were analyzed every 10 weeks for up to 60 weeks, when frogs were then switched to a fish oil-supplemented diet. lipid analysi ... | 2015 | 25878281 |
| neutrophil elastase activates protease-activated receptor-2 (par2) and transient receptor potential vanilloid 4 (trpv4) to cause inflammation and pain. | proteases that cleave protease-activated receptor-2 (par(2)) at arg(36)↓ser(37) reveal a tethered ligand that binds to the cleaved receptor. par(2) activates transient receptor potential (trp) channels of nociceptive neurons to induce neurogenic inflammation and pain. although proteases that cleave par(2) at non-canonical sites can trigger distinct signaling cascades, the functional importance of the par(2)-biased agonism is uncertain. we investigated whether neutrophil elastase, a biased agonis ... | 2015 | 25878251 |
| a new nomenclature of xenopus laevis chromosomes based on the phylogenetic relationship to silurana/xenopus tropicalis. | xenopus laevis (xla) is an allotetraploid species which appears to have undergone whole-genome duplication after the interspecific hybridization of 2 diploid species closely related to silurana/xenopus tropicalis (xtr). previous cdna fluorescence in situ hybridization (fish) experiments have identified 9 sets of homoeologous chromosomes in x. laevis, in which 8 sets correspond to chromosomes 1-8 of x. tropicalis (xtr1-xtr8), and the last set corresponds to a fusion of xtr9 and xtr10. in addition ... | 2015 | 25871511 |
| a heteromeric potassium channel involved in the modulation of the plasma membrane potential is essential for the survival of african trypanosomes. | discovery of novel drug targets may lead to improved treatment of trypanosomiasis. we characterize here 2 gene products of trypanosoma brucei that are essential for the growth of bloodstream form (bsf) parasites, as shown by rna interference (rnai)-mediated down-regulation of the individual mrnas. the primary sequences of the 2 proteins--protein encoded by gene tb927.1.4450 (tbk1) and protein encoded by gene tb927.9.4820 (tbk2)--indicate that both belong to the family of putative, ca(2+)-activat ... | 2015 | 25868728 |
| identification of a novel dehydration responsive gene, drp10, from the african clawed frog, xenopus laevis. | during periods of environmental stress a number of different anuran species employ adaptive strategies to promote survival. our study found that in response to dehydration (i.e., loss of total body water content), the african clawed frog (xenopus laevis) increased the expression of a novel gene (drp10) that encodes a structural homolog of the freeze-responsive fr10 protein found in wood frogs. similar to fr10, the drp10 protein was found to also contain a highly conserved n-terminal cleavable si ... | 2015 | 25866033 |
| germ layer formation during xenopus embryogenesis: the balance between pluripotency and differentiation. | the african clawed frog, xenopus laevis, has long been a model animal for the studies in the fields of animal cloning, developmental biology, biochemistry, cell biology, and physiology. with the aid of xenopus, major molecular mechanisms that are involved in embryonic development have been understood. germ layer formation is the first event of embryonic cellular differentiation, which is induced by a few key maternal factors and subsequently by zygotic signals. meanwhile, another type of signals ... | 2015 | 25862657 |
| a gamut of undiscovered electrophysiological effects produced by tityus serrulatus toxin 1 on nav-type isoforms. | in the last decades, ts1 has not only been the subject of many studies, it has also been considered as a very useful tool to investigate nav channels and to explore the exact role of nav channels in channelopathies. ts1 is believed to modulate the activation process of nav upon interaction at the neurotoxin binding site 4. our aim was to carry out an in depth functional characterization of ts1 on a wide array of nav channels, in order to investigate its mechanism of action and to verify if ts1 c ... | 2015 | 25862296 |
| toxic mechanisms of copper oxide nanoparticles in epithelial kidney cells. | cuo nps have previously been reported as toxic to a range of cell cultures including kidney epithelial cells from the frog, xenopus laevis (a6). here we examine the molecular mechanisms affecting toxicity of cu in different forms and particle sizes. a6 cells were exposed to ionic cu (cu2+) or cuo particles of three different sizes: cuo nps of 6 nm (np6), larger poly-dispersed cuo nps of <100 nm (poly) and cuo micro particles of <5 μm (micro), at 200 μm, equal to 12.7 mg cu/l. poly was significan ... | 2015 | 25862124 |
| a requirement for hedgehog signaling in thyroid hormone-induced postembryonic intestinal remodeling. | intestinal remodeling during amphibian metamorphosis has long been studied as a model for the formation of the adult organs in vertebrates, especially the formation of adult organ-specific stem cells. like all other processes during metamorphosis, this process is controlled by thyroid hormone (t3), which affects cell fate and behavior through transcriptional regulation of target genes by binding to t3 receptors (trs). earlier studies have shown that sonic hedgehog (shh) is induced by t3 in the d ... | 2015 | 25859319 |
| rapid method to express and purify human membrane protein using the xenopus oocyte system for functional and low-resolution structural analysis. | progress toward elucidating the 3d structures of eukaryotic membrane proteins has been hampered by the lack of appropriate expression systems. recent work using the xenopus oocyte as a novel expression system for structural analysis demonstrates the capability of providing not only the significant amount of protein yields required for structural work but also the expression of eukaryotic membrane proteins in a more native and functional conformation. there is a long history using the oocyte expr ... | 2015 | 25857785 |
| functional characterization of the human facilitative glucose transporter 12 (glut12) by electrophysiological methods. | glut12 is a member of the facilitative family of glucose transporters. the goal of this study was to characterize the functional properties of glut12, expressed in xenopus laevis oocytes, using radiotracer and electrophysiological methods. our results showed that glut12 is a facilitative sugar transporter with substrate selectivity: d-glucose ≥ α-methyl-d-glucopyranoside (α-mg) > 2-deoxy-d-glucose(2-dog) > d-fructose = d-galactose. α-mg is a characteristic substrate of the na(+)/glucose (sglt) f ... | 2015 | 25855082 |
| a molecular characterization of the agonist binding site of a nematode cys-loop gaba receptor. | cys-loop gaba receptors represent important targets for human chemotherapeutics and insecticides and are potential targets for novel anthelmintics (nematicides). however, compared with insect and mammalian receptors, little is known regarding the pharmacological characteristics of nematode cys-loop gaba receptors. here we have investigated the agonist binding site of the cys-loop gaba receptor unc-49 (hco-unc-49) from the parasitic nematode haemonchus contortus. | 2015 | 25850584 |
| host-defense and trefoil factor family peptides in skin secretions of the mawa clawed frog xenopus boumbaensis (pipidae). | peptidomic analysis of norepinephrine-stimulated skin secretions from the octoploid mawa clawed frog xenopus boumbaensis loumont, 1983 led to the identification and characterization of 15 host-defense peptides belonging to the magainin (two peptides), peptide glycine-leucine-amide (pgla; three peptides), xenopsin precursor fragment (xpf; three peptides), caerulein precursor fragment (cpf; two peptides), and caerulein precursor fragment-related peptide (cpf-rp; five peptides) families. in additio ... | 2015 | 25849343 |
| atp4a is required for development and function of the xenopus mucociliary epidermis - a potential model to study proton pump inhibitor-associated pneumonia. | proton pump inhibitors (ppis), which target gastric h(+)/k(+)atpase (atp4), are among the most commonly prescribed drugs. ppis are used to treat ulcers and as a preventative measure against gastroesophageal reflux disease in hospitalized patients. ppi treatment correlates with an increased risk for airway infections, i.e. community- and hospital-acquired pneumonia. the cause for this correlation, however, remains elusive. the xenopus embryonic epidermis is increasingly being used as a model to s ... | 2015 | 25848696 |
| fmrp regulates neurogenesis in vivo in xenopus laevis tadpoles. | fragile x syndrome (fxs) is the leading known monogenic form of autism and the most common form of inherited intellectual disability. fxs results from silencing the fmr1 gene during embryonic development, leading to loss of fragile x mental retardation protein (fmrp), an rna-binding protein that regulates mrna transport, stability, and translation. fxs is commonly thought of as a disease of synaptic dysfunction, however, fmrp expression is lost early in embryonic development, well before most sy ... | 2017 | 25844398 |
| chytrid fungus infections in laboratory and introduced xenopus laevis populations: assessing the risks for u.k. native amphibians. | the chytrid fungus batrachochytrium dendrobatidis (bd) is notorious amongst current conservation biology challenges, responsible for mass mortality and extinction of amphibian species. world trade in amphibians is implicated in global dissemination. exports of south african xenopus laevis have led to establishment of this invasive species on four continents. bd naturally infects this host in africa and now occurs in several introduced populations. however, no previous studies have investigated t ... | 2015 | 25843959 |
| reprint of "baroreflex function in anurans from different environments". | anurans from terrestrial environments have an enhanced ability to maintain mean arterial blood pressure (pm) through lymph mobilization in response to desiccation or hemorrhage compared with semiaquatic or aquatic species. because short term blood pressure homeostasis is regulated by arterial baroreceptors, we compared baroreflex function in three species of anurans that span a range of environments, dehydration tolerance and an ability to maintain pm with dehydration and hemorrhage. the cardiac ... | 2015 | 25843212 |
| desflurane increased the activity of excitatory amino-acid carrier 1 (eaac1) expressed in xenopus oocytes. | desflurane is a volatile anaesthetic agent with neuroprotective properties. excitatory amino-acid carrier 1 (eaac1) may be neuroprotective by taking up glutamate and cysteine. therefore, the effects of desflurane on eaac1 activity were investigated in this study. eaac1 was expressed in xenopus laevis oocytes. two-electrode voltage-clamping technique was used to record membrane currents upon exposure to l-glutamate (30 μm) in the presence or absence of desflurane (0.4, 1.0, 2.0, 2.6, or 3.2mm). c ... | 2015 | 25840279 |
| in vivo investigation of cilia structure and function using xenopus. | cilia are key organelles in development and homeostasis. the ever-expanding complement of cilia associated proteins necessitates rapid and tractable models for in vivo functional investigation. xenopus laevis provides an attractive model for such studies, having multiple ciliated populations, including primary and multiciliated tissues. the rapid external development of xenopus and the large cells make it an especially excellent platform for imaging studies. here we present embryological and cel ... | 2015 | 25837389 |
| reproductive strategies of the kangaroo leech, marsupiobdella africana (glossiphoniidae). | the kangaroo leech, marsupiobdella africana, is a hermaphroditic organism, with insemination taking place by the planting of a spermatophore on another leech. spermatophores are mostly planted on the anterior of the recipient leech, but not always. several spermatophores may be planted by different leeches on a single recipient. the spermatophore consists of two side by side lobes. within minutes from planting of the spermatophore, the contents are squeezed out and into the body of the recipient ... | 2015 | 25830114 |
| evidence for a revised ion/substrate coupling stoichiometry of gaba transporters. | plasma membrane γ-aminobutyric acid (gaba) transporters (gats) are electrogenic transport proteins that couple the cotranslocation of na(+), cl(-), and gaba across the plasma membrane of neurons and glia. a fundamental property of the transporter that determines its ability to concentrate gaba in cells and, hence, regulate synaptic and extra-synaptic gaba concentrations, is the ion/substrate coupling stoichiometry. here, we scrutinized the currently accepted 2 na(+):1 cl(-):1 gaba stoichiometry ... | 2015 | 25824654 |
| a lactate and formate transporter in the intraerythrocytic malaria parasite, plasmodium falciparum. | the intraerythrocytic malaria parasite relies primarily on glycolysis to fuel its rapid growth and reproduction. the major byproduct of this metabolism, lactic acid, is extruded into the external medium. in this study, we show that the human malaria parasite plasmodium falciparum expresses at its surface a member of the microbial formate-nitrite transporter family (pffnt), which, when expressed in xenopus laevis oocytes, transports both formate and lactate. the transport characteristics of pffnt ... | 2015 | 25823844 |
| a 90 day safety assessment of genetically modified rice expressing cry1ab/1ac protein using an aquatic animal model. | in fields of transgenic bt rice, frogs are exposed to bt proteins through consumption of both target and nontarget insects. in the present study, we assessed the risk posed by transgenic rice expressing a cry1ab/1ac fusion protein (huahui 1, hh1) on the development of xenopus laevis. for 90 days, froglets were fed a diet with 30% hh1 rice, 30% parental rice (minghui 63, mh63), or no rice as a control. body weight and length were measured every 15 days. after sacrificing the froglets, we performe ... | 2015 | 25822065 |
| toxicity evaluation of a new zn-doped cuo nanocomposite with highly effective antibacterial properties. | the increased resistances to conventional antibiotics determine a strong need for new antibacterials, and specific syntheses at the nanoscale promise to be helpful in this field. a novel zinc-doped copper oxide nanocomposite (nzn-cuo) has been recently sonochemically synthesized and successfully tested also against multi-drug resistant bacteria. after synthesis and characterization of the physicochemical properties, the new nzn-cuo is here evaluated by the frog embyo teratogenesis assay-xenopus ... | 2015 | 25820130 |
| 17α-ethinylestradiol can disrupt hemoglobin catabolism in amphibians. | different chemical substances, which enter the environment due to anthropogenic influences, can affect the endocrine system and influence development and physiology of aquatic animals. one of these endocrine disrupting chemicals is the synthetic estrogen, 17α-ethinylestradiol (ee2), which is a main component of various oral contraceptives and demonstrably affects many different aquatic vertebrates at extremely low concentrations by feminization phenomena. the aim of the present study was to inve ... | 2015 | 25819740 |
| an in vivo screen to identify candidate neurogenic genes in the developing xenopus visual system. | neurogenesis in the brain of xenopus laevis continues throughout larval stages of development. we developed a 2-tier screen to identify candidate genes controlling neurogenesis in xenopus optic tectum in vivo. first, microarray and nanostring analyses were used to identify candidate genes that were differentially expressed in sox2-expressing neural progenitor cells or their neuronal progeny. then an in vivo, time-lapse imaging-based screen was used to test whether morpholinos against 34 candidat ... | 2015 | 25818835 |
| screening breeding sites of the common toad (bufo bufo) in england and wales for evidence of endocrine disrupting activity. | anuran amphibians are often present in agricultural landscapes and may therefore be exposed to chemicals in surface waters used for breeding. we used passive accumulation devices (spmd and pocis) to sample contaminants from nine breeding sites of the common toad (bufo bufo) across england and wales, measuring endocrine activity of the extracts in a recombinant yeast androgen screen (yas) and yeast estrogen screen (yes) and an in vitro vitellogenin induction screen in primary culture of xenopus l ... | 2015 | 25817886 |
| the influence of electromagnetic pollution on living organisms: historical trends and forecasting changes. | current technologies have become a source of omnipresent electromagnetic pollution from generated electromagnetic fields and resulting electromagnetic radiation. in many cases this pollution is much stronger than any natural sources of electromagnetic fields or radiation. the harm caused by this pollution is still open to question since there is no clear and definitive evidence of its negative influence on humans. this is despite the fact that extremely low frequency electromagnetic fields were ... | 2015 | 25811025 |
| site-specific methylation of notch1 controls the amplitude and duration of the notch1 response. | physiologically, notch signal transduction plays a pivotal role in differentiation; pathologically, notch signaling contributes to the development of cancer. transcriptional activation of notch target genes involves cleavage of the notch receptor in response to ligand binding, production of the notch intracellular domain (nicd), and nicd migration into the nucleus and assembly of a coactivator complex. posttranslational modifications of the nicd are important for its transcriptional activity and ... | 2015 | 25805888 |
| crystal structure of a xenopus laevis skin proto-type galectin, close to but distinct from galectin-1. | xenopus laevis (african clawed frog) has two types of proto-type galectins that are similar to mammalian galectin-1 in amino acid sequence. one type, comprising xgalectin-ia and -ib, is regarded as being equivalent to galectin-1, and the other type, comprising xgalectin-va and -vb, is expected to be a unique galectin subgroup. the latter is considerably abundant in frog skin; however, its biological function remains unclear. we determined the crystal structures of two proto-type galectins, xgale ... | 2015 | 25804418 |
| functional characterization of the 1,5-benzodiazepine clobazam and its major active metabolite n-desmethylclobazam at human gaba(a) receptors expressed in xenopus laevis oocytes. | the 1,5-benzodiazepine clobazam is indicated for the adjunctive treatment of seizures associated with lennox-gastaut syndrome in patients 2 years of age or older in the united states, and for treatment of anxiety and various forms of epilepsy elsewhere. clobazam has been reported to exhibit different in vivo adverse effects and addiction liability profile than the classic 1,4-benzodiazepines. in this study, it was investigated whether the in vitro pharmacological properties of clobazam and its m ... | 2015 | 25798598 |
| regeneration of xenopus laevis spinal cord requires sox2/3 expressing cells. | spinal cord regeneration is very inefficient in humans, causing paraplegia and quadriplegia. studying model organisms that can regenerate the spinal cord in response to injury could be useful for understanding the cellular and molecular mechanisms that explain why this process fails in humans. here, we use xenopus laevis as a model organism to study spinal cord repair. histological and functional analyses showed that larvae at pre-metamorphic stages restore anatomical continuity of the spinal co ... | 2015 | 25797152 |
| rmnd5 from xenopus laevis is an e3 ubiquitin-ligase and functions in early embryonic forebrain development. | in saccharomyces cerevisiae the gid-complex functions as an ubiquitin-ligase complex that regulates the metabolic switch between glycolysis and gluconeogenesis. in higher organisms six conserved gid proteins form the ctlh protein-complex with unknown function. here we show that rmnd5, the gid2 orthologue from xenopus laevis, is an ubiquitin-ligase embedded in a high molecular weight complex. expression of rmnd5 is strongest in neuronal ectoderm, prospective brain, eyes and ciliated cells of the ... | 2015 | 25793641 |
| apoptosis and differentiation of xenopus tail-derived myoblasts by thyroid hormone. | the metamorphosis of anuran amphibians is induced by thyroid hormone (th). to study the molecular mechanisms underlying tail regression during metamorphosis, we established a cell line, xl-b4, from a xenopus laevis tadpole tail at a premetamorphic stage. the cells expressed myoblast markers and differentiated into myotubes in differentiation medium. xl-b4 cells expressing fluorescent proteins were transplanted into tadpole tails. at 5 days post-transplantation, fluorescence was observed in myotu ... | 2015 | 25791374 |
| ensemble-based virtual screening for cannabinoid-like potentiators of the human glycine receptor α1 for the treatment of pain. | the human glycine receptors (hglyrs) are chloride-selective ion channels that mediate inhibitory neurotransmission in the brain stem and spinal cord. they are also targets for compounds of potential use in analgesic therapies. here, we develop a strategy to discover analgesic drugs via structure-based virtual screening based on the recently published nmr structure of the hglyr-α1 transmembrane domain (pdb id: 2m6i ) and the critical role of residue s296 in hglyr-α1 potentiation by δ(9)-tetrahydr ... | 2015 | 25790278 |
| hdac1 regulates the proliferation of radial glial cells in the developing xenopus tectum. | in the developing central nervous system (cns), progenitor cells differentiate into progeny to form functional neural circuits. radial glial cells (rgs) are a transient progenitor cell type that is present during neurogenesis. it is thought that a combination of neural trophic factors, neurotransmitters and electrical activity regulates the proliferation and differentiation of rgs. however, it is less clear how epigenetic modulation changes rg proliferation. we sought to explore the effect of hi ... | 2015 | 25789466 |
| species-specific loss of sexual dimorphism in vocal effectors accompanies vocal simplification in african clawed frogs (xenopus). | phylogenetic studies can reveal patterns of evolutionary change, including the gain or loss of elaborate courtship traits in males. male african clawed frogs generally produce complex and rapid courtship vocalizations, whereas female calls are simple and slow. in a few species, however, male vocalizations are also simple and slow, suggesting loss of male-typical traits. here, we explore features of the male vocal organ that could contribute to loss in two species with simple, slow male calls. in ... | 2015 | 25788725 |
| ear manipulations reveal a critical period for survival and dendritic development at the single-cell level in mauthner neurons. | second-order sensory neurons are dependent on afferents from the sense organs during a critical period in development for their survival and differentiation. past research has mostly focused on whole populations of neurons, hampering progress in understanding the mechanisms underlying these critical phases. to move toward a better understanding of the molecular and cellular basis of afferent-dependent neuronal development, we developed a new model to study the effects of ear removal on a single ... | 2015 | 25787878 |
| third-generation electrokinetically pumped sheath-flow nanospray interface with improved stability and sensitivity for automated capillary zone electrophoresis-mass spectrometry analysis of complex proteome digests. | we have reported a set of electrokinetically pumped sheath flow nanoelectrospray interfaces to couple capillary zone electrophoresis with mass spectrometry. a separation capillary is threaded through a cross into a glass emitter. a side arm provides fluidic contact with a sheath buffer reservoir that is connected to a power supply. the potential applied to the sheath buffer drives electro-osmosis in the emitter to pump the sheath fluid at nanoliter per minute rates. our first-generation interfac ... | 2015 | 25786131 |
| a gustatory receptor tuned to d-fructose in antennal sensilla chaetica of helicoverpa armigera. | insect gustatory systems play important roles in food selection and feeding behaviors. in spite of the enormous progress in understanding gustation in drosophila, for other insects one of the key elements in gustatory signaling, the gustatory receptor (gr), is still elusive. in this study, we report that fructose elicits behavioral and physiological responses in helicoverpa armigera (harm) to fructose and identify the gustatory receptor for this sugar. using the proboscis extension reflex (per) ... | 2015 | 25784630 |