Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
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| long-range gap junctional signaling controls oncogene-mediated tumorigenesis in xenopus laevis embryos. | in addition to the immediate microenvironment, long-range signaling may be an important component of cancer. molecular-genetic analyses have implicated gap junctions-key mediators of cell-cell communication-in carcinogenesis. we recently showed that the resting voltage potential of distant cell groups is a key determinant of metastatic transformation and tumor induction. here, we show in the xenopus laevis model that gap junctional communication (gjc) is a modulator of the long-range bioelectric ... | 2014 | 25646081 |
| molecular phylogeny of pseudocapillaroides xenopi (moravec et cosgrov 1982) and development of a quantitative pcr assay for its detection in aquarium sediment. | we used high-fidelity pcr to amplify a portion of the small ribosomal subunit (18s rrna) of pseudocapillaroides xenopi, a nematode that parasitizes the skin of xenopus laevis. the 1113-bp amplicon was cloned, sequenced, and aligned with sequences from 22 other nematodes in the order trichocephalida; caenorhabditis elegans was used as the outgroup. maximum-likelihood and bayesian inference phylogenetic analyses clustered p. xenopi in a clade containing only members of the genus capillaria. our an ... | 0 | 25650974 |
| understanding early organogenesis using a simplified in situ hybridization protocol in xenopus. | organogenesis is the study of how organs are specified and then acquire their specific shape and functions during development. the xenopuslaevis embryo is very useful for studying organogenesis because their large size makes them very suitable for identifying organs at the earliest steps in organogenesis. at this time, the primary method used for identifying a specific organ or primordium is whole mount in situ hybridization with labeled antisense rna probes specific to a gene that is expressed ... | 2015 | 25651461 |
| cnrip1 is a regulator of eye and neural development in xenopus laevis. | cannabinoid receptor interacting protein 1 (cnrip1), which has been originally identified as the binding partner of cannabinoid receptor 1 (cnr1), is evolutionarily conserved throughout vertebrates, but its physiological function has been unknown. here, we identify a developmental role of cnrip1 using xenopus laevis embryos. during early embryogenesis, expression of xenopus laevis cnrip1 is highly restricted to the animal region of gastrulae where neural and eye induction occur, and afterward it ... | 2015 | 25652037 |
| microtubule-associated protein tau promotes neuronal class ii β-tubulin microtubule formation and axon elongation in embryonic xenopus laevis. | compared with its roles in neurodegeneration, much less is known about microtubule-associated protein tau's normal functions in vivo, especially during development. the external development and ease of manipulating gene expression of xenopus laevis embryos make them especially useful for studying gene function during early development. to study tau's functions in axon outgrowth, we characterized the most prominent tau isoforms of xenopus embryos and manipulated their expression. none of these fo ... | 2015 | 25656701 |
| histochemical analyses of biliary development during metamorphosis of xenopus laevis tadpoles. | in mammalian liver development, intrahepatic biliary morphogenesis takes place in periportal, but not in pericentral, regions. liver progenitor cells transiently form epithelial plate structures and then intrahepatic bile ducts around the portal veins under the influence of the mesenchyme. the present study was undertaken to histochemically examine normal biliary development and its dependence on the action of the thyroid hormone triiodothyronine (t3) in xenopus laevis tadpoles. in these tadpole ... | 2015 | 25660701 |
| development of a new approach for targeted gene editing in primordial germ cells using talens in xenopus. | a gene of interest can be efficiently modified using transcription activator-like effector nucleases (talens) (christian et al., 2010;li et al., 2011). however, if a target gene is essential for development, growth and fertility, use of talens with high mutagenic activity in f0 frogs could result in developmental disorders or sterility, which would reduce the number of f1 progeny and make f1 phenotypical analysis difficult. we used the 3' untranslated region of deadsouth gene (ds-3') of xenopus ... | 2015 | 25661867 |
| the ph sensitivity of aqp0 channels in tetraploid and diploid teleosts. | water homeostasis and the structural integrity of the vertebrate lens is partially mediated by aqp0 channels. emerging evidence indicates that external ph may be involved in channel gating. here we show that a tetraploid teleost, the atlantic salmon, retains 4 aqp0 genes (aqp0a1, -0a2, -0b1, and -0b2), which are highly, but not exclusively, expressed in the lens. functional characterization reveals that, although each paralog permeates water efficiently, the permeability is respectively shifted ... | 2015 | 25667219 |
| a functional correlate of severity in alternating hemiplegia of childhood. | mutations in atp1a3, the gene that encodes the α3 subunit of the na(+)/k(+) atpase, are the primary cause of alternating hemiplegia of childhood (ahc). correlations between different mutations and ahc severity were recently reported, with e815k identified in severe and d801n and g947r in milder cases. this study aims to explore the molecular pathological mechanisms in ahc and to identify functional correlates for mutations associated with different levels of disease severity. | 2015 | 25681536 |
| one-pot refolding of core histones from bacterial inclusion bodies allows rapid reconstitution of histone octamer. | we report an optimized method to purify and reconstitute histone octamer, which utilizes high expression of histones in inclusion bodies but eliminates the time consuming steps of individual histone purification. in the newly modified protocol, xenopus laevis h2a, h2b, h3, and h4 are expressed individually into inclusion bodies of bacteria, which are subsequently mixed together and denatured in 8m guanidine hydrochloride. histones are refolded and reconstituted into soluble octamer by dialysis a ... | 2015 | 25687285 |
| patterns of hypothalamic regionalization in amphibians and reptiles: common traits revealed by a genoarchitectonic approach. | most studies in mammals and birds have demonstrated common patterns of hypothalamic development highlighted by the combination of developmental regulatory genes (genoarchitecture), supporting the notion of the hypothalamus as a component of the secondary prosencephalon, topologically rostral to the diencephalon. in our comparative analysis we have summarized the data on the expression patterns of different transcription factors and neuroactive substances, used as anatomical markers, in the devel ... | 2015 | 25691860 |
| influence of oxidized purine processing on strand directionality of mismatch repair. | replicative dna polymerases are high fidelity enzymes that misincorporate nucleotides into nascent dna with a frequency lower than [1/10(5)], and this precision is improved to about [1/10(7)] by their proofreading activity. because this fidelity is insufficient to replicate most genomes without error, nature evolved postreplicative mismatch repair (mmr), which improves the fidelity of dna replication by up to 3 orders of magnitude through correcting biosynthetic errors that escaped proofreading. ... | 2015 | 25694431 |
| monitoring of rhodopsin trafficking and mistrafficking in live photoreceptors. | outer segment (os) directed trafficking is required for accomplishing the extremely high concentration of rhodopsin and explicitly high photon sensitivity of rod photoreceptor cells. aberrant targeting of rhodopsin often leads to blinding disorders, due to various mechanisms causing rhodopsin mislocalization. until recently, it has been challenging to monitor the dynamics of rhodopsin biogenesis and trafficking. here, we describe a new method to visualize rhodopsin trafficking in living and unfi ... | 2015 | 25697531 |
| mismatch repair-dependent metabolism of o6-methylguanine-containing dna in xenopus laevis egg extracts. | the cytotoxicity of sn1-type alkylating agents such as n-methyl-n'-nitrosourea (mnu), n-methyl-n'-nitro-n-nitrosoguanidine (mnng), or the cancer chemotherapeutics temozolomide, dacarbazine and streptozotocin has been ascribed to the persistence of o(6)-methylguanine ((me)g) in genomic dna. one hypothesis posits that (me)g toxicity is caused by futile attempts of the mismatch repair (mmr) system to process (me)g/c or (me)g/t mispairs arising during replication, while an alternative proposal sugge ... | 2015 | 25697728 |
| valproate-induced neurodevelopmental deficits in xenopus laevis tadpoles. | autism spectrum disorder (asd) is increasingly thought to result from low-level deficits in synaptic development and neural circuit formation that cascade into more complex cognitive symptoms. however, the link between synaptic dysfunction and behavior is not well understood. by comparing the effects of abnormal circuit formation and behavioral outcomes across different species, it should be possible to pinpoint the conserved fundamental processes that result in disease. here we use a novel mode ... | 2015 | 25698756 |
| molecular mechanism of chrdl1-mediated x-linked megalocornea in humans and in xenopus model. | chordin-like 1 (chrdl1) mutations cause non-syndromic x-linked megalocornea (xmc) characterized by enlarged anterior eye segments. mosaic corneal degeneration, presenile cataract and secondary glaucoma are associated with xmc. beside that chrdl1 encodes ventroptin, a secreted bone morphogenetic protein (bmp) antagonist, the molecular mechanism of xmc is not well understood yet. in a family with broad phenotypic variability of xmc, we identified the novel chrdl1 frameshift mutation c.807_808deltc ... | 2015 | 25712132 |
| histone h2a and h4 n-terminal tails are positioned by the mep50 wd repeat protein for efficient methylation by the prmt5 arginine methyltransferase. | the protein arginine methyltransferase prmt5 is complexed with the wd repeat protein mep50 (also known as wdr77 or androgen coactivator p44) in vertebrates in a tetramer of heterodimers. mep50 is hypothesized to be required for protein substrate recruitment to the catalytic domain of prmt5. here we demonstrate that the cross-dimer mep50 is paired with its cognate prmt5 molecule to promote histone methylation. we employed qualitative methylation assays and a novel ultrasensitive continuous assay ... | 2015 | 25713080 |
| histone titration against the genome sets the dna-to-cytoplasm threshold for the xenopus midblastula transition. | during early development, animal embryos depend on maternally deposited rna until zygotic genes become transcriptionally active. before this maternal-to-zygotic transition, many species execute rapid and synchronous cell divisions without growth phases or cell cycle checkpoints. the coordinated onset of transcription, cell cycle lengthening, and cell cycle checkpoints comprise the midblastula transition (mbt). a long-standing model in the frog, xenopus laevis, posits that mbt timing is controlle ... | 2015 | 25713373 |
| ferritin h subunit gene is specifically expressed in melanophore precursor-derived white pigment cells in which reflecting platelets are formed from stage ii melanosomes in the periodic albino mutant of xenopus laevis. | "white pigment cells" are derived from melanophore precursors and contain both melanophore-specific and iridophore-specific pigment organelles. whereas melanophores differentiate in the wild type regenerating tail, white pigment cells appear in the regenerating tail in the periodic albino mutant (a(p)/a(p)) of xenopus laevis. the localization and density of white pigment cells in the mutant regenerating tail are similar to those of melanophores in the wild type regenerating tail. here, white pig ... | 2015 | 25715760 |
| prominent amphibian (xenopus laevis) tadpole type iii interferon response to the frog virus 3 ranavirus. | ranaviruses (iridoviridae) are posing an increasing threat to amphibian populations, with anuran tadpoles being particularly susceptible to these viral infections. moreover, amphibians are the most basal phylogenetic class of vertebrates known to possess both type i and type iii interferon (ifn)-mediated immunity. moreover, little is known regarding the respective roles of the ifn mediators in amphibian antiviral defenses. accordingly, we transcriptionally and functionally compared the amphibian ... | 2015 | 25717104 |
| [on the classification of the cleavage patterns in amphibian embryos]. | this paper presents a brief survey and preliminary classification of embryonic cleavage patterns in the class amphibia. we use published data on 41 anuran and 22 urodele species concerning the character of the third cleavage furrow (latitudinal or longitudinal) and the stage of transition from synchronous to asynchronous blastomere divisions in the animal hemisphere (4-8-celled stage, 8-16-celled stage or later). based on this, four patterns of amphibian embryonic cleavage are recognized, and an ... | 2015 | 25720261 |
| [on a contribution of boris balinsky to the comparative and ecological embryology of amphibians]. | the outstanding embryologist boris ivanovich balinsky (1905-1997) worked in the soviet union up to 1941 and in south africa since 1949. his experimental studies fulfilled during the soviet period of his scientific career mainly on the embryos of the caudate amphibians are widely known. after moving to africa (johannesburg), he continued the research of amphibian development, with using those possibilities, which were offered by the diverse fauna of local anura. other embryologists started comple ... | 2015 | 25720271 |
| allosteric modulation of the glycine receptor activated by agonists differing in efficacy. | the glycine receptor (glyr) is the predominant inhibitory neurotransmitter receptor in the brainstem and spinal cord but is also found in higher brain regions. glyr function is affected by a variety of allosteric modulators including drugs of abuse, such as ethanol and inhalants and the ubiquitous divalent cation zinc. two-electrode voltage-clamp experiments were conducted on xenopus laevis oocytes expressing wild-type α1 homomeric glycine receptors to compare the degree of enhancement produced ... | 2015 | 25721789 |
| a regression-based differential expression detection algorithm for microarray studies with ultra-low sample size. | global gene expression analysis using microarrays and, more recently, rna-seq, has allowed investigators to understand biological processes at a system level. however, the identification of differentially expressed genes in experiments with small sample size, high dimensionality, and high variance remains challenging, limiting the usability of these tens of thousands of publicly available, and possibly many more unpublished, gene expression datasets. we propose a novel variable selection algorit ... | 2015 | 25738861 |
| manipulation and in vitro maturation of xenopus laevis oocytes, followed by intracytoplasmic sperm injection, to study embryonic development. | amphibian eggs have been widely used to study embryonic development. early embryonic development is driven by maternally stored factors accumulated during oogenesis. in order to study roles of such maternal factors in early embryonic development, it is desirable to manipulate their functions from the very beginning of embryonic development. conventional ways of gene interference are achieved by injection of antisense oligonucleotides (oligos) or mrna into fertilized eggs, enabling under- or over ... | 2015 | 25742326 |
| rns60, a charge-stabilized nanostructure saline alters xenopus laevis oocyte biophysical membrane properties by enhancing mitochondrial atp production. | we have examined the effects of rns60, a 0.9% saline containing charge-stabilized oxygen nanobubble-based structures. rns60 is generated by subjecting normal saline to taylor-couette-poiseuille (tcp) flow under elevated oxygen pressure. this study, implemented in xenopus laevis oocytes, addresses both the electrophysiological membrane properties and parallel biological processes in the cytoplasm. intracellular recordings from defolliculated x. laevis oocytes were implemented in: (1) air oxygenat ... | 2015 | 25742953 |
| more similar than you think: frog metamorphosis as a model of human perinatal endocrinology. | hormonal control of development during the human perinatal period is critically important and complex with multiple hormones regulating fetal growth, brain development, and organ maturation in preparation for birth. genetic and environmental perturbations of such hormonal control may cause irreversible morphological and physiological impairments and may also predispose individuals to diseases of adulthood, including diabetes and cardiovascular disease. endocrine and molecular mechanisms that reg ... | 2015 | 25744725 |
| xenopus laevis oocytes as a model system for studying the interaction between asbestos fibres and cell membranes. | the mode of interaction of asbestos fibres with cell membranes is still debatable. one reason is the lack of a suitable and convenient cellular model to investigate the causes of asbestos toxicity. we studied the interaction of asbestos fibres with xenopus laevis oocytes, using electrophysiological and morphological methods. oocytes are large single cells, with a limited ability to endocytose molecular ligands; we therefore considered these cells to be a good model for investigating the nature o ... | 2015 | 25745069 |
| phospholipase c and d regulation of src, calcium release and membrane fusion during xenopus laevis development. | this review emphasizes how lipids regulate membrane fusion and the proteins involved in three developmental stages: oocyte maturation to the fertilizable egg, fertilization and during first cleavage. decades of work show that phosphatidic acid (pa) releases intracellular calcium, and recent work shows that the lipid can activate src tyrosine kinase or phospholipase c during xenopus fertilization. numerous reports are summarized to show three levels of increase in lipid second messengers inositol ... | 2015 | 25748412 |
| efficient retina formation requires suppression of both activin and bmp signaling pathways in pluripotent cells. | retina formation requires the correct spatiotemporal patterning of key regulatory factors. while it is known that repression of several signaling pathways lead to specification of retinal fates, addition of only noggin, a known bmp antagonist, can convert pluripotent xenopus laevis animal cap cells to functional retinal cells. the aim of this study is to determine the intracellular molecular events that occur during this conversion. surprisingly, blocking bmp signaling alone failed to mimic nogg ... | 2015 | 25750435 |
| direct observation of ca(2+) -induced calmodulin conformational transitions in intact xenopus laevis oocytes by (19) f nmr spectroscopy. | the ca(2+) -mediated conformational transition of the protein calmodulin (cam) is essential to a variety of signal transduction pathways. whether the transition in living cells is similar to that observed in buffer is not known. here, we report the direct observation by (19) f nmr spectroscopy of the transition of the ca(2+) -free and -bound forms in xenopus laevis oocytes at different ca(2+) levels. we find that the ca(2+) -bound cam population increased greatly upon binding the target protein ... | 2015 | 25753548 |
| cloning of interleukin-10 from african clawed frog (xenopus tropicalis), with the finding of il-19/20 homologue in the il-10 locus. | interleukin-10 (il-10) is a pleiotropic cytokine that plays an important role in immune system. in the present study, the il-10 gene of african clawed frog (xenopus tropicalis) was first cloned, and its expression pattern and 3d structure were also analyzed. the frog il-10 mrna encoded 172 amino acids which possessed several conserved features found in il-10s from other species, including five-exon/four-intron genomic structure, conserved four cysteine residues, il-10 family motif, and six α-hel ... | 2015 | 25759841 |
| investigating polymorphisms in membrane-associated transporter protein slc45a2, using sucrose transporters as a model. | solute carrier family 45 member 2 encodes the melanosomal membrane protein, membrane-associated transporter protein (matp), of unknown function, that is required for normal melanin synthesis. the present study analyzed the effects of two human matp mutations, d93n, which causes oculocutaneous albinism 4 (oca4), and l374f, which is correlated with light pigmentation in european populations. corresponding mutations were produced in the related and well-characterized sucrose transporter from rice, ... | 2015 | 25760657 |
| proteomics analysis of xenopus laevis gonad tissue following chronic exposure to atrazine. | atrazine is the most commonly detected pesticide contaminant in ground and surface water. previous studies have shown that atrazine is an endocrine disruptor owing to its adverse effects on the male reproductive system in several vertebrates, but very few molecular mechanisms for these effects have been revealed. in the present study, xenopus laevis were exposed to 100 ppb of atrazine for 120 d, and then the isobaric tags for relative and absolute quantitation (itraq) technique was used to detec ... | 2015 | 25760937 |
| endogenous gradients of resting potential instructively pattern embryonic neural tissue via notch signaling and regulation of proliferation. | biophysical forces play important roles throughout embryogenesis, but the roles of spatial differences in cellular resting potentials during large-scale brain morphogenesis remain unknown. here, we implicate endogenous bioelectricity as an instructive factor during brain patterning in xenopus laevis. early frog embryos exhibit a characteristic hyperpolarization of cells lining the neural tube; disruption of this spatial gradient of the transmembrane potential (vmem) diminishes or eliminates the ... | 2015 | 25762681 |
| developmentally regulated post-translational modification of nucleoplasmin controls histone sequestration and deposition. | nucleoplasmin (npm) is an abundant histone chaperone in vertebrate oocytes and embryos. during embryogenesis, regulation of npm histone binding is critical for its function in storing and releasing maternal histones to establish and maintain the zygotic epigenome. here, we demonstrate that xenopus laevis npm post-translational modifications (ptms) specific to the oocyte and egg promote either histone deposition or sequestration, respectively. mass spectrometry and npm phosphomimetic mutations us ... | 2015 | 25772360 |
| unique gene expression profile of the proliferating xenopus tadpole tail blastema cells deciphered by rna-sequencing analysis. | organ regenerative ability depends on the animal species and the developmental stage. the molecular bases for variable organ regenerative ability, however, remain unknown. previous studies have identified genes preferentially expressed in the blastema tissues in various animals, but transcriptome analysis of the isolated proliferating blastema cells has not yet been reported. in the present study, we used rna-sequencing analysis to analyze the gene expression profile of isolated proliferating bl ... | 2015 | 25775398 |
| papc mediates self/non-self-distinction during snail1-dependent tissue separation. | cleft-like boundaries represent a type of cell sorting boundary characterized by the presence of a physical gap between tissues. we studied the cleft-like ectoderm-mesoderm boundary in xenopus laevis and zebrafish gastrulae. we identified the transcription factor snail1 as being essential for tissue separation, showed that its expression in the mesoderm depends on noncanonical wnt signaling, and demonstrated that it enables paraxial protocadherin (papc) to promote tissue separation through two n ... | 2015 | 25778923 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| targeted gene disruption in xenopus laevis using crispr/cas9. | 2015 | 25897376 | |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |