Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| subfunctionalization of paralogous aryl hydrocarbon receptors from the frog xenopus laevis: distinct target genes and differential responses to specific agonists in a single cell type. | gene duplication confers genetic redundancy that can facilitate subfunctionalization, the partitioning of ancestral functions between paralogs. we capitalize on a recent genome duplication in xenopus laevis (african clawed frog) to interrogate possible functional differentiation between alloalleles of the aryl hydrocarbon receptor (ahr), a ligand-activated transcription factor that mediates toxicity of dioxin-like compounds and plays a role in the physiology and development of the cardiovascular ... | 2017 | 27994169 |
| retinoid-like compounds produced by phytoplankton affect embryonic development of xenopus laevis. | teratogenic effects, which were remarkably similar to those induced by retinoic acids, have been seen in wild frogs indicating possible source of retinoids in the environment. recent studies indicate that some cyanobacterial species can contain teratogenic retinoic acids (ras) and their analogues. retinoids are known to regulate important processes such as differentiation, development, and embryogenesis. the study investigated the effects of exudates (extracellular compounds) of two cyanobacteri ... | 2017 | 27992848 |
| bicarbonate sensing in mouse cortical astrocytes during extracellular acid/base disturbances. | the present study suggests that the electrogenic sodium-bicarbonate cotransporter, nbce1, supported by carbonic anhydrase ii, caii, provides an efficient mechanism of bicarbonate sensing in cortical astrocytes. this mechanism is proposed to play a major role in setting the phi responses to extracellular acid/base challenges in astrocytes. a decrease in extracellular [hco3- ] during isocapnic acidosis and isohydric hypocapnia, or an increase in intracellular [hco3- ] during hypercapnic acidosis, ... | 2017 | 27981578 |
| evaluation of a commercial electro-kinetically pumped sheath-flow nanospray interface coupled to an automated capillary zone electrophoresis system. | capillary zone electrophoresis-electrospray ionization-mass spectrometry (cze-esi-ms) is attracting renewed attention for proteomic and metabolomic analysis. an important reason for this interest is the maturation and commercialization of interfaces for coupling cze with esi-ms. one of these interfaces is an electro-kinetically pumped sheath flow nanospray interface developed by the dovichi group, in which a very low sheath flow is generated based on electroosmosis within a glass emitter. cmp sc ... | 2017 | 27981343 |
| δβγ-enac is inhibited by cftr but stimulated by camp in xenopus laevis oocytes. | the epithelial sodium channel (enac) and the cystic fibrosis transmembrane conductance regulator (cftr) chloride channel critically regulate airway surface liquid by driving fluid absorption and secretion, respectively. their functional interplay is complex and incompletely understood. enac is a heteromeric channel with three well-characterized subunits (α, β, and γ). in humans, an additional δ-enac subunit exists in lung and several other tissues, where it may replace the α-subunit to form δβγ- ... | 2017 | 27941075 |
| controlling the messenger: regulated translation of maternal mrnas in xenopus laevis development. | the selective translation of maternal mrnas encoding cell-fate determinants drives the earliest decisions of embryogenesis that establish the vertebrate body plan. this chapter will discuss studies in xenopus laevis that provide insights into mechanisms underlying this translational control. xenopus has been a powerful model organism for many discoveries relevant to the translational control of maternal mrnas because of the large size of its oocytes and eggs that allow for microinjection of mole ... | 2017 | 27975270 |
| primary brain calcification causal pit2 transport-knockout variants can exert dominant negative effects on wild-type pit2 transport function in mammalian cells. | primary brain calcification (pbc) is a neurodegenerative disorder characterized by calcium-phosphate deposits in the basal ganglia and often also other areas of the brain. the prevalent clinical manifestations are cognitive impairment, neuropsychiatric symptoms, and movement disorders. in recent years, monoallelic variants in slc20a2, which encodes the type iii sodium-dependent inorganic phosphate (pi) transporter 2 (pit2), have been linked to the familial form of pbc in 40-50% of the families r ... | 2017 | 27943094 |
| xenopus laevis neuronal cell adhesion molecule (nrcam): plasticity of a cam in the developing nervous system. | neuron-glial-related cell adhesion molecule (nrcam) is a neuronal cell adhesion molecule of the l1 immunoglobulin superfamily, which plays diverse roles during nervous system development including axon growth and guidance, synapse formation, and formation of the myelinated nerve. perturbations in nrcam function cause a wide variety of disorders, which can affect wiring and targeting of neurons, or cause psychiatric disorders as well as cancers through abnormal modulation of signaling events. in ... | 2017 | 27942869 |
| thyroid hormone-induced activation of notch signaling is required for adult intestinal stem cell development during xenopus laevis metamorphosis. | in xenopus laevis intestine during metamorphosis, the larval epithelial cells are removed by apoptosis, and the adult epithelial stem (ae) cells appear concomitantly. they proliferate and differentiate to form the adult epithelium (ep). thyroid hormone (th) is well established to trigger this remodeling by regulating the expression of various genes including notch receptor. to study the role of notch signaling, we have analyzed the expression of its components, including the ligands (dll and jag ... | 2017 | 27870267 |
| use of xenopus laevis oocytes to study auxin transport. | xenopus laevis oocytes are an expression system that is particularly well suited for the characterization of membrane transporters. oocytes possess only very little endogenous transport systems and therefore transporters can be studied with a high signal-to-noise ratio. this book chapter provides the basic methods to use xenopus oocytes for the characterization of transporters by radiotracer experiments. while the methods described here were established to study auxin transport they can easily b ... | 2017 | 27864772 |
| nemo-like kinase 1 (nlk1) and paraxial protocadherin (papc) cooperatively control xenopus gastrulation through regulation of wnt/planar cell polarity (pcp) signaling. | the wnt/planar cell polarity (pcp) pathway directs cell migration during vertebrate gastrulation and is essential for proper embryonic development. paraxial protocadherin (papc, gene symbol pcdh8.2) is an important activator of wnt/pcp signaling during xenopus gastrulation, but how papc activity is controlled is incompletely understood. here we show that nemo-like kinase 1 (nlk1), an atypical mitogen-activated protein (map) kinase, physically associates with the c-terminus of papc. this interact ... | 2017 | 27875771 |
| reversible developmental stasis in response to nutrient availability in the xenopus laevis central nervous system. | many organisms confront intermittent nutrient restriction (nr), but the mechanisms to cope with nutrient fluctuations during development are not well understood. this is particularly true of the brain, the development and function of which is energy intensive. here we examine the effects of nutrient availability on visual system development in xenopus laevis tadpoles. during the first week of development, tadpoles draw nutrients from maternally provided yolk. upon yolk depletion, animals forage ... | 2017 | 27875263 |
| clustered xenopus keratin genes: a genomic, transcriptomic, and proteomic analysis. | keratin genes belong to the intermediate filament superfamily and their expression is altered following morphological and physiological changes in vertebrate epithelial cells. keratin genes are divided into two groups, type i and ii, and are clustered on vertebrate genomes, including those of xenopus species. various keratin genes have been identified and characterized by their unique expression patterns throughout ontogeny in xenopus laevis; however, compilation of previously reported and newly ... | 2017 | 27842699 |
| cftr-β-catenin interaction regulates mouse embryonic stem cell differentiation and embryonic development. | cystic fibrosis transmembrane conductance regulator (cftr) is a camp-regulated anion channel capable of conducting both cl- and hco3-, mutations of which cause cystic fibrosis (cf), a common autosomal recessive disease. although cf patients are known to have varied degree of developmental problems, the biological role of cftr in embryonic development remains elusive. here, we show that cftr is functionally expressed in mouse escs. cftr-/- mescs exhibit dramatic defect in mesendoderm differentiat ... | 2017 | 27834953 |
| electrophysiological activity of a neurotoxic fraction from the venom of box jellyfish carybdea marsupialis. | carybdea marsupialis is a widely distributed box jellyfish found in the mediterranean and in the tropical waters of the caribbean sea. its venom is a complex mixture of biologically active compounds that are used to catch prey. in order to evaluate the activity of the neurotoxins in the venom, bioassays were carried out using the marine crab ocypode quadrata. the proteins with neurotoxic effect were partially purified using low-pressure liquid chromatography techniques. gel filtration (sephadex ... | 2017 | 27815048 |
| developmental changes in head movement kinematics during swimming in xenopus laevis tadpoles. | during the post-embryonic developmental growth of animals, a number of physiological parameters such as locomotor performance, dynamics and behavioural repertoire are adjusted to match the requirements determined by changes in body size, proportions and shape. moreover, changes in movement parameters also cause changes in the dynamics of self-generated sensory stimuli, to which motion-detecting sensory systems have to adapt. here, we examined head movements and swimming kinematics of xenopus lae ... | 2017 | 27811303 |
| conservatism and variability of gene expression profiles among homeologous transcription factors in xenopus laevis. | xenopus laevis has an allotetraploid genome of 3.1gb, in contrast to the diploid genome of a closely related species, xenopus tropicalis. here, we identified 412 genes (189 homeolog pairs, one homeologous gene cluster pair, and 28 singletons) encoding transcription factors (tfs) in the x. laevis genome by comparing them with their orthologs from x. tropicalis. those genes include the homeobox gene family (mix/bix, lhx, nkx, paired, pou, and vent), sox, fox, pax, dmrt, hes, gata, t-box, and some ... | 2017 | 27810169 |
| the antidepressant bupropion is a negative allosteric modulator of serotonin type 3a receptors. | the fda-approved antidepressant and smoking cessation drug bupropion is known to inhibit dopamine and norepinephrine reuptake transporters, as well as nicotinic acetylcholine receptors (nachrs) which are cation-conducting members of the cys-loop superfamily of ion channels, and more broadly pentameric ligand-gated ion channels (plgics). in the present study, we examined the ability of bupropion and its primary metabolite hydroxybupropion to block the function of cation-selective serotonin type 3 ... | 2017 | 27671323 |
| a sister chromatid cohesion assay using xenopus egg extracts. | cell-free extracts made from xenopus laevis eggs enable us to recapitulate many chromosomal events associated with cell cycle progression in a test tube. when sperm chromatin is incubated with these extracts, it is first duplicated within an assembled nucleus, and is then transformed into mitotic chromosomes, in each of which sister chromatids are juxtaposed with each other in a cohesin-dependent manner. here we describe our protocols for assembling duplicated chromosomes using egg extracts, alo ... | 2017 | 27797070 |
| characterization of human short chain dehydrogenase/reductase sdr16c family members related to retinol dehydrogenase 10. | all-trans-retinoic acid (ra) is a bioactive derivative of vitamin a that serves as an activating ligand for nuclear transcription factors, retinoic acid receptors. ra biosynthesis is initiated by the enzymes that oxidize retinol to retinaldehyde. it is well established that retinol dehydrogenase 10 (rdh10, sdr16c4), which belongs to the 16c family of the short chain dehydrogenase/reductase (sdr) superfamily of proteins, is the major enzyme responsible for the oxidation of retinol to retinaldehyd ... | 2017 | 27793605 |
| methylmercury induces an initial increase in gaba-evoked currents in xenopus oocytes expressing α1 and α6 subunit-containing gabaa receptors. | early onset effects of methylmercury (mehg) on recombinant α1β2γ2s or α6β2γ2s subunit-containing gabaa receptors were examined. these are two of the most prevalent receptor types found in cerebellum-a consistent target of mehg-induced neurotoxicity. heterologously expressed receptors were used in order to: (1) isolate receptor-mediated events from extraneous effects of mehg due to stimulation of the receptor secondary to increased release of gaba seen with mehg in neurons in situ and (2) limit t ... | 2017 | 27720918 |
| tissue-specific selenium accumulation and toxicity in adult female xenopus laevis chronically exposed to elevated dietary selenomethionine. | selenium (se) is a developmental toxicant that is also capable of altering the bioenergetic and endocrine status of adult fish. to date, aquatic ecotoxicological research has predominantly focused on the toxic effects of se in fish, and minimal information has been published related to amphibians. the objective of the present study was to investigate the potential toxicity associated with chronically elevated dietary se consumption in adult female amphibians utilizing the model species xenopus l ... | 2017 | 27666932 |
| rhythm generation, coordination, and initiation in the vocal pathways of male african clawed frogs. | central pattern generators (cpgs) in the brain stem are considered to underlie vocalizations in many vertebrate species, but the detailed mechanisms underlying how motor rhythms are generated, coordinated, and initiated remain unclear. we addressed these issues using isolated brain preparations of xenopus laevis from which fictive vocalizations can be elicited. advertisement calls of male x. laevis that consist of fast and slow trills are generated by vocal cpgs contained in the brain stem. brai ... | 2017 | 27760822 |
| characterization of cadmium chloride-induced bip accumulation in xenopus laevis a6 kidney epithelial cells. | endoplasmic reticulum (er) stress can result in the accumulation of unfolded/misfolded protein in the er lumen, which can trigger the unfolded protein response (upr) resulting in the activation of various genes including immunoglobulin-binding protein (bip; also known as glucose-regulated protein 78 or hspa5). bip, an er heat shock protein 70 (hsp70) family member, binds to unfolded protein, inhibits their aggregation and re-folds them in an atp-dependent manner. while cadmium, an environmental ... | 2017 | 27746171 |
| characterization of tilapia (oreochromis niloticus) aldehyde reductase (akr1a1) gene, promoter and expression pattern in benzo-a-pyrene exposed fish. | this study planned to isolation and characterization of akr1a1 cdna from bap injected nile tilapia (oreochromis niloticus), comparison of its characteristic structures with those of other species, characterization of akr1a1 gene and promoter, and investigation of akr1a1 mrna expression in various organs of bap injected tilapia. the cdna was 1172 bp long which includes an open reading frame of 975 bp encoding a 324 amino acids protein and a stop codon. the sequence showed 3' and 5' non-coding reg ... | 2017 | 27800707 |
| the extracellular c-loop domain plays an important role in the cell adhesion function of aquaporin 0. | although aquaporin 0 (aqp0) is a member of the aqp family, it has limited water permeability compared with other members. aqp0 may also have cell adhesion-related functions, but the evidence is still limited. here, we studied the relationship of aqp0 to cell adhesion and determined the region required for cell adhesion. | 2017 | 27754715 |
| identification and comparative analyses of siamois cluster genes in xenopus laevis and tropicalis. | two siamois-related homeobox genes siamois (sia1) and twin (sia2), have been reported in xenopus laevis. these genes are expressed in the blastula chordin- and noggin-expressing (bcne) center and the nieuwkoop center, and have complete secondary axis-inducing activity when over-expressed on the ventral side of the embryo. using whole genome sequences of x. tropicalis and x. laevis, we identified two additional siamois-related genes, which are tandemly duplicated near sia1 and sia2 to form the si ... | 2017 | 27522305 |
| from the cover: functional analysis reveals glutamate and gamma-aminobutyric acid-gated chloride channels as targets of avermectins in the carmine spider mite. | the carmine spider mite, tetranychus cinnabarinus (boisduval), is one of the most important pests in the agricultural industry. avermectins, as efficient acaricides, have been extensively used in the mite control. the targets for avermectins in mammals, nematodes, and insects had already been identified as γ-aminobutyric acid and glutamate chloride channels. however, the targets for avermectins in mites are still not clear. here, we report the cloning of 5 full-length glutamate-gated chloride ch ... | 2017 | 27742867 |
| primordial germ cell isolation from xenopus laevis embryos. | primordial germ cells (pgcs) are the precursors to the gametes and have the unique ability to retain full developmental potential. however, the mechanism(s) and gene-network(s) necessary for their proper specification and development are poorly understood. this is due, in part, to the challenges that must be overcome in order to identify and isolate pgcs during critical stages of development. two distinct mechanisms have been characterized to specify the germ cell lineage in vertebrates: inducti ... | 2017 | 27734352 |
| genome organization of the vg1 and nodal3 gene clusters in the allotetraploid frog xenopus laevis. | extracellular factors belonging to the tgf-β family play pivotal roles in the formation and patterning of germ layers during early xenopus embryogenesis. here, we show that the vg1 and nodal3 genes of xenopus laevis are present in gene clusters on chromosomes xla1l and xla3l, respectively, and that both gene clusters have been completely lost from the syntenic s chromosome regions. the presence of gene clusters and chromosome-specific gene loss were confirmed by cdna fish analyses. sequence and ... | 2017 | 27720224 |
| insulin-like growth factor 1 regulation of proliferation and differentiation of xenopus laevis myogenic cells in vitro. | to understand the mechanism of muscle remodeling during xenopus laevis metamorphosis, we examined the in vitro effect of insulin-like growth factor 1 (igf-1) on growth and differentiation of three different-fate myogenic cell populations: tadpole tail, tadpole dorsal, and young adult leg muscle. igf-1 promoted growth and differentiation of both tail and leg myogenic cells only under conditions where these cells could proliferate. inhibition of cell proliferation by dna synthesis inhibitor cytosi ... | 2017 | 27699652 |
| the african clawed frog xenopus laevis: a model organism to study regeneration of the central nervous system. | while an injury to the central nervous system (cns) in humans and mammals is irreversible, amphibians and teleost fish have the capacity to fully regenerate after severe injury to the cns. xenopus laevis has a high potential to regenerate the brain and spinal cord during larval stages (47-54), and loses this capacity during metamorphosis. the optic nerve has the capacity to regenerate throughout the frog's lifespan. here, we review cns regeneration in frogs, with a focus in x. laevis, but also p ... | 2017 | 27693567 |
| genomic organization and modulation of gene expression of the tgf-β and fgf pathways in the allotetraploid frog xenopus laevis. | inductive interactions mediated by the tgf-β and fgf-mapk pathways are essential for specification of the germ layers and embryonic body axes during early vertebrate embryogenesis. tgf-β and fgf ligands signal through receptor ser/thr and tyr kinases, respectively, and these signaling pathways cross-talk to regulate transcription and cell behavior. the allotetraploid xenopus laevis and its ancestral diploid xenopus tropicalis are versatile model organisms with which to study the inductive intera ... | 2017 | 27692744 |
| effects of freezing and activation on membrane quality and dna damage in xenopus tropicalis and xenopus laevis spermatozoa. | there is growing concern over the effect of sperm cryopreservation on dna integrity and the subsequent development of offspring generated from this cryopreserved material. in the present study, membrane integrity and dna stability of xenopus laevis and xenopus tropicalis spermatozoa were evaluated in response to cryopreservation with or without activation, a process that happens upon exposure to water to spermatozoa of some aquatic species. a dye exclusion assay revealed that sperm plasma membra ... | 2017 | 27692061 |
| electrophysiological actions of synthetic cathinones on monoamine transporters. | products containing psychoactive synthetic cathinones, such as mephedrone and 3,4-methylenedioxypyrovalerone (mdpv) are prevalent in our society. synthetic cathinones are structurally similar to methamphetamine, and numerous synthetics have biological activity at dopamine, serotonin, and norepinephrine transporters. importantly, monoamine transporters co-transport sodium ions along with their substrate, and movement of substrates and ions through the transporter can generate measurable ionic cur ... | 2017 | 27677783 |
| an implantable eng detector with in-system velocity selective recording (vsr) capability. | detection and classification of electroneurogram (eng) signals in the peripheral nervous system can be achieved by velocity selective recording (vsr) using multi-electrode arrays. this paper describes an implantable vsr-based eng recording system representing a significant development in the field since it is the first system of its type that can record naturally evoked eng and be interfaced wirelessly using a low data rate transcutaneous link. the system consists of two cmos asics one of which ... | 2017 | 27638107 |
| gene expression analysis of developing cell groups in the pretectal region of xenopus laevis. | our previous analysis of progenitor domains in the pretectum of xenopus revealed three molecularly distinct anteroposterior subdivisions, identified as precommissural (pcp), juxtacommissural (jcp), and commissural (cop) histogenetic domains (morona et al. [2011] j comp neurol 519:1024-1050). here we analyzed at later developmental stages the nuclei derived from these areas, attending to their gene expression patterns and histogenesis. transcription-factor gene markers were used to selectively ma ... | 2017 | 27539385 |
| the sox transcriptional factors: functions during intestinal development in vertebrates. | the intestine has long been studied as a model for adult stem cells due to the life-long self-renewal of the intestinal epithelium through the proliferation of the adult intestinal stem cells. recent evidence suggests that the formation of adult intestinal stem cells in mammals takes place during the thyroid hormone-dependent neonatal period, also known as postembryonic development, which resembles intestinal remodeling during frog metamorphosis. studies on the metamorphosis in xenopus laevis ha ... | 2017 | 27567710 |
| translational profiling of retinal ganglion cell optic nerve regeneration in xenopus laevis. | unlike adult mammals, adult frogs regrow their optic nerve following a crush injury, making xenopus laevis a compelling model for studying the molecular mechanisms that underlie neuronal regeneration. using translational ribosome affinity purification (trap), a method to isolate ribosome-associated mrnas from a target cell population, we have generated a transcriptional profile by rna-seq for retinal ganglion cells (rgc) during the period of recovery following an optic nerve injury. based on bio ... | 2017 | 27471010 |
| genes coding for cyclin-dependent kinase inhibitors are fragile in xenopus. | cell proliferation is strictly regulated by the dosage balance among cell-cycle regulators such as cdk/cyclin complexes and cdk-inhibitors. even in the allotetraploid genome of xenopus laevis, the dosage balance must be maintained for animals to stay alive, and the duplicated homeologous genes seem to have gradually changed, through evolution, resulting in the best genes for them to thrive. in the xenopus laevis genome, while homeologous gene pairs of cdks are fundamentally maintained and a few ... | 2017 | 27393661 |
| expression pattern and pharmacological characterisation of two novel alternative splice variants of the glutamate-gated chloride channel in the small brown planthopper laodelphax striatellus. | glutamate-gated chloride channels (glucl) mediate fast inhibitory neurotransmission in invertebrate nervous systems. although only one glucl gene was presented in insects, it showed diverse alternative splicing that was speculated could affect channel function and pharmacology. | 2017 | 27302648 |
| in vitro models of cranial neural crest development toward toxicity tests: frog, mouse, and human. | during craniofacial development, cranial neural crest (nc)-derived mesenchymal cells migrate to pharyngeal arches and contribute extensively to neurons, schwann cells, smooth muscle cells, osteoblasts, chondrocytes, and odontoblasts, forming maxillofacial structures. in vitro models using model organism cells, such as african clawed frog (xenopus laevis) and mouse (mus musculus), were developed to understand cellular and molecular mechanisms of cranial nc development. recent studies using human ... | 2017 | 27299949 |
| sex chromosome differentiation and the w- and z-specific loci in xenopus laevis. | genetic sex-determining systems in vertebrates include two basic types of heterogamety; xx (female)/xy (male) and zz (male)/zw (female) types. the african clawed frog xenopus laevis has a zz/zw-type sex-determining system. in this species, we previously identified a w-specific sex (female)-determining gene dmw, and specified w and z chromosomes, which could be morphologically indistinguishable (homomorphic). in addition to dmw, we most recently discovered two genes, named scanw and ccdc69w, and ... | 2017 | 27297884 |
| robust identification of ptbp1-dependent splicing events by a junction-centric approach in xenopus laevis. | regulation of alternative splicing is an important process for cell differentiation and development. down-regulation of ptbp1, a regulatory rna-binding protein, leads to developmental skin defects in xenopus laevis. to identify ptbp1-dependent splicing events potentially related to the phenotype, we conducted rnaseq experiments following ptbp1 depletion. we systematically compared exon-centric and junction-centric approaches to detect differential splicing events. we showed that the junction-cen ... | 2017 | 27546377 |
| exploring the functions of nonclassical mhc class ib genes in xenopus laevis by the crispr/cas9 system. | a large family of highly related and clustered xenopus nonclassical mhc class ib (xnc) genes influences xenopus laevis immunity and potentially other physiological functions. using rna interference (rnai) technology, we previously demonstrated that one of xnc genes, xnc10.1, is critical for the development and function of a specialized innate t (it) cell population. however, rnai limitation such as a variable and unstable degree of gene silencing in f0 and f1 generations is hampering a thorough ... | 2017 | 27318386 |
| xenmine: a genomic interaction tool for the xenopus community. | the xenopus community has embraced recent advances in sequencing technology, resulting in the accumulation of numerous rna-seq and chip-seq datasets. however, easily accessing and comparing datasets generated by multiple laboratories is challenging. thus, we have created a central space to view, search and analyze data, providing essential information on gene expression changes and regulatory elements present in the genome. xenmine (www.xenmine.org) is a user-friendly website containing publishe ... | 2017 | 27157655 |
| pharmacological characterization of histamine-gated chloride channels from the housefly musca domestica. | the biogenic amine histamine (ha) is not only the neurotransmitter of photoreceptors but also has important roles in mechanosensory reception, temperature preference, sleep and olfactory processing in insects. two cdnas (mdhcla and mdhclb) that encode ha-gated chloride channel subunits (mdhcla and mdhclb) were cloned from the housefly musca domestica. the crnas were injected into xenopus laevis oocytes to examine the functions and pharmacological characteristics of mdhcla and mdhclb channels usi ... | 2017 | 27139242 |
| xenopus: leaping forward in kidney organogenesis. | while kidney donations stagnate, the number of people in need of kidney transplants continues to grow. although transplanting culture-grown organs is years away, pursuing the engineering of the kidney de novo is a valid means of closing the gap between the supply and demand of kidneys for transplantation. the structural organization of a mouse kidney is similar to that of humans. therefore, mice have traditionally served as the primary model system for the study of kidney development. the mouse ... | 2017 | 27099217 |
| evaluating the teratogenicity of the selective ß3-adrenoceptor agonist, cl 316.243 hydrate by employing fetax (frog embryo teratogenesis assay). | in this study, the frog embryo teratogenesis assay (fetax - xenopus) technique was employed to evaluate the potential teratogenicity of the selective ß-adrenoceptor (ar) agonist, cl 316.243. in this context, cl 316.243 was applied to the south african clawed frog (xenopus laevis) embryos. the media containing the cl 316.24-exposed embryos were monitored and changed/replaced once every 24 hours. using fetax, we determined the minimum concentrations to inhibit growth (mcig) for cl 316.243. the 96- ... | 2017 | 27063898 |
| evaluation of microtransplantation of rat brain neurolemma into xenopus laevis oocytes as a technique to study the effect of neurotoxicants on endogenous voltage-sensitive ion channels. | microtransplantation of mammalian brain neurolemma into the plasma membrane of xenopus oocytes is used to study ion channels in their native form as they appear in the central nervous system. use of microtransplanted neurolemma is advantageous for various reasons: tissue can be obtained from various sources and at different developmental stages; ion channels and receptors are present in their native configuration in their proper lipid environment along with appropriate auxiliary subunits; allowi ... | 2017 | 27063102 |
| xenopus genomic data and browser resources. | the two species of xenopus most commonly used in biomedical research are the diploid xenopus (silurana) tropicalis and the tetraploid xenopus laevis. the x. tropicalis genome sequence has been available since 2010 and this year the x. laevis, genome from two distinct genetic backgrounds has been published. multiple genome assemblies available for both species and transcriptomic and epigenetic data sets are growing rapidly, all of which are available from a variety of web resources. this review d ... | 2017 | 27039265 |
| genome-wide analysis of dorsal and ventral transcriptomes of the xenopus laevis gastrula. | rna sequencing has allowed high-throughput screening of differential gene expression in many tissues and organisms. xenopus laevis is a classical embryological and cell-free extract model system, but its genomic sequence had been lacking due to difficulties arising from allotetraploidy. there is currently much excitement surrounding the release of the completed x. laevis genome (version 9.1) by the joint genome institute (jgi), which provides a platform for genome-wide studies. here we present a ... | 2017 | 27016259 |
| generation of a xenopus laevis f1 albino j strain by genome editing and oocyte host-transfer. | completion of the xenopus laevis genome sequence from inbred j strain animals has facilitated the generation of germline mutant x. laevis using targeted genome editing. in the last few years, numerous reports have demonstrated that talens are able to induce mutations in f0 xenopus embryos, but none has demonstrated germline transmission of such mutations in x. laevis. in this report we used the oocyte host-transfer method to generate mutations in both tyrosinase homeologs and found highly-penetr ... | 2017 | 26993591 |
| expanding the genetic toolkit in xenopus: approaches and opportunities for human disease modeling. | the amphibian model xenopus, has been used extensively over the past century to study multiple aspects of cell and developmental biology. xenopus offers advantages of a non-mammalian system, including high fecundity, external development, and simple housing requirements, with additional advantages of large embryos, highly conserved developmental processes, and close evolutionary relationship to higher vertebrates. there are two main species of xenopus used in biomedical research, xenopus laevis ... | 2017 | 27109192 |
| extinction of an introduced warm-climate alien species, xenopus laevis, by extreme weather events. | invasive, non-native species represent a major threat to biodiversity worldwide. the african amphibian xenopus laevis is widely regarded as an invasive species and a threat to local faunas. populations originating at the western cape, south africa, have been introduced on four continents, mostly in areas with a similar mediterranean climate. some introduced populations are also established in cooler environments where persistence for many decades suggests a capacity for long-term adaptation. in ... | 2017 | 26430383 |
| 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 |
| kbot55, purified from buthus occitanus tunetanus venom, represents the first member of a novel α-ktx subfamily. | kbot55 is a 39 amino acid peptide isolated from the venom of the tunisian scorpion buthus occitanus tunetanus. this peptide is cross-linked by 3 disulfide bridges and has a molecular mass of 4128.65da. kbot55 is very low represented in the venom and thus represents a challenge for biochemical characterization. in this study, kbot55 has been subjected to a screening on ion channels expressed in xenopus laevis oocytes. it was found that kbot55 targets voltage-gated potassium channels with high aff ... | 2016 | 26079392 |
| metamorphic remodeling of the olfactory organ of the african clawed frog, xenopus laevis. | the amphibian olfactory system undergoes massive remodeling during metamorphosis. the transition from aquatic olfaction in larvae to semiaquatic or airborne olfaction in adults requires anatomical, cellular, and molecular modifications. these changes are particularly pronounced in pipidae, whose adults have secondarily adapted to an aquatic life style. in the fully aquatic larvae of xenopus laevis, the main olfactory epithelium specialized for sensing water-borne odorous substances lines the pri ... | 2016 | 26294036 |
| quantitative analysis of filament branch orientation in listeria actin comet tails. | several bacterial and viral pathogens hijack the host actin cytoskeleton machinery to facilitate spread and infection. in particular, listeria uses arp2/3-mediated actin filament nucleation at the bacterial surface to generate a branched network that will help propel the bacteria. however, the mechanism of force generation remains elusive due to the lack of high-resolution three-dimensional structural data on the spatial organization of the actin mother and daughter (i.e., branch) filaments with ... | 2016 | 26497103 |
| cell cycle synchronization in xenopus egg extracts. | many important discoveries in cell cycle research have been made using cell-free extracts prepared from the eggs of the south african clawed frog xenopus laevis. these extracts efficiently support the key nuclear functions of the eukaryotic cell cycle in vitro under apparently the same controls that exist in vivo. the xenopus cell-free system is therefore uniquely suited to the study of the mechanisms, dynamics and integration of cell cycle regulated processes at a biochemical level. here, we de ... | 2016 | 26254920 |
| developing xenopus embryos recover by compacting and expelling single wall carbon nanotubes. | single wall carbon nanotubes are high aspect ratio nanomaterials being developed for use in materials, technological and biological applications due to their high mechanical stiffness, optical properties and chemical inertness. because of their prevalence, it is inevitable that biological systems will be exposed to nanotubes, yet studies of the effects of nanotubes on developing embryos have been inconclusive and are lacking for single wall carbon nanotubes exposed to the widely studied model or ... | 2016 | 26153061 |
| effects of dietary exposure of polycyclic musk hhcb on the metamorphosis of xenopus laevis. | the compound 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-[γ]-2-benzopyrane (hhcb; galaxolide, chemical abstracts service number 1222-05-5) is a synthetic musk used extensively as a fragrance in many consumer products and classified as an emerging pollutant. the ecotoxicological information available for hhcb addresses exposure via water, but this compound is frequently adsorbed into particulate matter. the goal of the present study was to assess the effects of dietary exposure to seve ... | 2016 | 26472276 |
| catalytic activity of human carbonic anhydrase isoform ix is displayed both extra- and intracellularly. | most carbonic anhydrases catalyse the reversible conversion of carbon dioxide to protons and bicarbonate, either as soluble cytosolic enzymes, in or at intracellular organelles, or at the extracellular face of the cell membrane as membrane-anchored proteins. carbonic anhydrase isoform ix (ca ix), a membrane-bound enzyme with catalytic activity at the extracellular membrane surface, has come to prominence in recent years because of its association with hypoxic tissue, particularly tumours, often ... | 2016 | 26470855 |
| bumetanide derivatives aqb007 and aqb011 selectively block the aquaporin-1 ion channel conductance and slow cancer cell migration. | aquaporins (aqps) in the major intrinsic family of proteins mediate fluxes of water and other small solutes across cell membranes. aqp1 is a water channel, and under permissive conditions, a nonselective cation channel gated by cgmp. in addition to mediating fluid transport, aqp1 expression facilitates rapid cell migration in cell types including colon cancers and glioblastoma. work here defines new pharmacological derivatives of bumetanide that selectively inhibit the ion channel, but not the w ... | 2016 | 26467039 |
| phosphorylation of rs1 (rsc1a1) steers inhibition of different exocytotic pathways for glucose transporter sglt1 and nucleoside transporter cnt1, and an rs1-derived peptide inhibits glucose absorption. | cellular uptake adapts rapidly to physiologic demands by changing transporter abundance in the plasma membrane. the human gene rsc1a1 codes for a 67-kda protein named rs1 that has been shown to induce downregulation of the sodium-d-glucose cotransporter 1 (sglt1) and of the concentrative nucleoside transporter 1 (cnt1) in the plasma membrane by blocking exocytosis at the golgi. injecting rs1 fragments into xenopus laevis oocytes expressing sglt1 or cnt1 and measuring the expressed uptake of α-me ... | 2016 | 26464324 |
| a curcumin analog, go-y078, effectively inhibits angiogenesis through actin disorganization. | the inhibition of angiogenesis is a theoretically ideal chemotherapy for cancer, but there remains room for improvement. most inhibitors of angiogenesis approved to date target vascular endothelial growth factors (vegfs); however, vegfs are only one of the many classes of participant in tumor angiogenesis. because tumor angiogenesis is orchestrated by many components, including growth factors, signal transducers, and effectors, its regulation exhibits redundancy. curcumin can associate with many ... | 2016 | 26459768 |
| complicated behavior of g-quadruplexes and evaluating g-quadruplexes' ligands in various systems mimicking cellular circumstance. | environments surrounding g-rich sequences remarkably affect the conformations of these structures. a proper evaluation system mimicking the crowded environment in a cell with macromolecules should be developed to perform structural and functional studies on g-quadruplexes. in this study, the topology and stability of a g-quadruplex formed by human telomeric repeat sequences were investigated in a macromolecule-crowded environment created by polyethylene glycol 200 (peg200), tumor cell extract, a ... | 2016 | 28955851 |
| proteomics of xenopus development. | modern mass spectrometry-based methods provide an exciting opportunity to characterize protein expression in the developing embryo. we have employed an isotopic labeling technology to quantify the expression dynamics of nearly 6000 proteins across six stages of development in xenopus laevis from the single stage zygote through the mid-blastula transition and the onset of organogenesis. approximately 40% of the proteins show significant changes in expression across the development stages. the exp ... | 2016 | 26396253 |
| phosphorylation at serine 52 and 635 does not alter the transport properties of glucosinolate transporter atgtr1. | little is known about how plants regulate transporters of defense compounds. in a. thaliana, glucosinolates are transported between tissues by npf2.10 (atgtr1) and npf2.11 (atgtr2). mining of the phosphat4.0 database showed two cytosol exposed phosphorylation sites for atgtr1 and one membrane-buried phosphorylation site for atgtr2. in this study, we investigate whether mutation of the two potential regulatory sites of atgtr1 affected transport of glucosinolates in xenopus oocytes. characterizati ... | 2016 | 26340317 |
| adaptive plasticity of spino-extraocular motor coupling during locomotion in metamorphosing xenopus laevis. | during swimming in the amphibian italic! xenopus laevis, efference copies of rhythmic locomotor commands produced by the spinal central pattern generator (cpg) can drive extraocular motor output appropriate for producing image-stabilizing eye movements to offset the disruptive effects of self-motion. during metamorphosis, italic! x. laevisremodels its locomotor strategy from larval tail-based undulatory movements to bilaterally synchronous hindlimb kicking in the adult. this change in propulsive ... | 2016 | 27103674 |
| selective inhibition of the kinase dyrk1a by targeting its folding process. | autophosphorylation of amino-acid residues is part of the folding process of various protein kinases. conventional chemical screening of mature kinases has missed inhibitors that selectively interfere with the folding process. here we report a cell-based assay that evaluates inhibition of a kinase at a transitional state during the folding process and identify a folding intermediate-selective inhibitor of dual-specificity tyrosine-phosphorylation-regulated kinase 1a (dyrk1a), which we refer to a ... | 2016 | 27102360 |
| single-cell mass spectrometry for discovery proteomics: quantifying translational cell heterogeneity in the 16-cell frog (xenopus) embryo. | we advance mass spectrometry from a cell population-averaging tool to one capable of quantifying the expression of diverse proteins in single embryonic cells. our instrument combines capillary electrophoresis (ce), electrospray ionization, and a tribrid ultrahigh-resolution mass spectrometer (hrms) to enable untargeted (discovery) proteomics with ca. 25 amol lower limit of detection. ce-μesi-hrms enabled the identification of 500-800 nonredundant protein groups by measuring 20 ng, or <0.2% of th ... | 2016 | 26756663 |
| homology-driven assembly of non-redundant protein sequence sets (nomess) for mass spectrometry. | to enable mass spectrometry (ms)-based proteomic studies with poorly characterized organisms, we developed a computational workflow for the homology-driven assembly of a non-redundant reference sequence dataset. in the automated pipeline, translated dna sequences (e.g. ests, rna deep-sequencing data) are aligned to those of a closely related and fully sequenced organism. representative sequences are derived from each cluster and joined, resulting in a non-redundant reference set representing the ... | 2016 | 26743511 |
| reappraising the effects of artemisinin on the atpase activity of pfatp6 and serca1a e255l expressed in xenopus laevis oocytes. | 2016 | 26733217 | |
| assessing differences in toxicity and teratogenicity of three phthalates, diethyl phthalate, di-n-propyl phthalate, and di-n-butyl phthalate, using xenopus laevis embryos. | phthalates, compounds used to add flexibility to plastics, are ubiquitous in the environment. in particular, the diethyl (dep), di-n-propyl (dnpp), and di-n-butyl (dbp) phthalates were found to exert detrimental effects in both mammalian and non-mammalian studies, with toxic effects varying according to alkyl chain length. embryos of xenopus laevis, the african clawed frog, have been used to assess toxicity and teratogenicity of several compounds and serves as a model for assessing adverse and t ... | 2016 | 26730679 |
| hydrophobic interactions between the s5 segment and the pore helix stabilizes the closed state of slo2.1 potassium channels. | under normal physiological conditions, slo2.1k(+) channels are in a closed state unless activated by an elevation in [na(+)]i. fenamates such as niflumic acid also activate slo2.1. previous studies suggest that activation of slo2.1 channels is mediated by a conformational change in the selectivity filter, and not a widening of the aperture formed by the s6 segment bundle crossing as occurs in voltage-gated k(+) channels. it is unclear how binding of na(+) or fenamates is allosterically linked to ... | 2016 | 26724206 |
| identifying domains of efhc1 involved in ciliary localization, ciliogenesis, and the regulation of wnt signaling. | efhc1 encodes a ciliary protein that has been linked to juvenile myoclonic epilepsy. in ectodermal explants, derived from xenopus laevis embryos, the morpholino-mediated down-regulation of efhc1b inhibited multiciliated cell formation. in those ciliated cells that did form, axoneme but not basal body formation was inhibited. efhc1b morphant embryos displayed defects in central nervous system (cns) and neural crest patterning that were rescued by a efhc1b-gfp chimera. efhc1b-gfp localized to cili ... | 2016 | 26783883 |
| differential requirement of bone morphogenetic protein receptors ia (alk3) and ib (alk6) in early embryonic patterning and neural crest development. | bone morphogenetic proteins regulate multiple processes in embryonic development, including early dorso-ventral patterning and neural crest development. bmps activate heteromeric receptor complexes consisting of type i and type ii receptor-serine/threonine kinases. bmp receptors ia and ib, also known as alk3 and alk6 respectively, are the most common type i receptors that likely mediate most bmp signaling events. since early expression patterns and functions in xenopus laevis development have no ... | 2016 | 26780949 |
| lens regeneration from the cornea requires suppression of wnt/β-catenin signaling. | the frog, xenopus laevis, possesses a high capacity to regenerate various larval tissues, including the lens, which is capable of complete regeneration from the cornea epithelium. however, the molecular signaling mechanisms of cornea-lens regeneration are not fully understood. previous work has implicated the involvement of the wnt signaling pathway, but molecular studies have been very limited. iris-derived lens regeneration in the newt (wolffian lens regeneration) has shown a necessity for act ... | 2016 | 26778749 |
| using frogs faces to dissect the mechanisms underlying human orofacial defects. | in this review i discuss how xenopus laevis is an effective model to dissect the mechanisms underlying orofacial defects. this species has been particularly useful in studying the understudied structures of the developing face including the embryonic mouth and primary palate. the embryonic mouth is the first opening between the foregut and the environment and is critical for adult mouth development. the final step in embryonic mouth formation is the perforation of a thin layer of tissue covering ... | 2016 | 26778163 |
| ventricular cell fate can be specified until the onset of myocardial differentiation. | the mechanisms that govern specification of various cell types that constitute vertebrate heart are not fully understood. whilst most studies of heart development have utilised the mouse embryo, we have used an alternative model, embryos of the frog xenopus laevis, which permits direct experimental manipulation of a non-essential heart. we show that in this model pluripotent animal cap explants injected with cardiogenic factor gata4 mrna express pan-myocardial as well as ventricular and proepica ... | 2016 | 26776863 |
| high and low gaba sensitivity α4β2δ gabaa receptors are expressed in xenopus laevis oocytes with divergent stoichiometries. | gabaa receptors that contain the α4 and δ subunits are thought to be located extrasynaptically, mediating tonic currents elicited by low concentrations of gaba. these α4βδ receptors are modulated by neurosteroids and certain anesthetics, identifying them as important drug targets in research. however, pharmacological studies on these receptors have often yielded variable results, possibly due to the expression of receptors in different stoichiometries or arrangements. in this study, we injected ... | 2016 | 26774457 |
| proper notch activity is necessary for the establishment of proximal cells and differentiation of intermediate, distal, and connecting tubule in xenopus pronephros development. | notch signaling in pronephros development has been shown to regulate establishment of glomus and proximal tubule, but how notch signal works on competency of pronephric anlagen during the generation of pronephric components remains to be understood. | 2016 | 26773453 |
| retracted: the anaphase-promoting complex/cyclosome is essential for entry into meiotic m-phase. | vertebrate immature oocytes are arrested at prophase of meiosis i (mi). hormonal stimulation breaks this prophase-i arrest and induces re-entry into mi. the mechanism underlying meiotic resumption remains largely elusive. here, we demonstrate that the anaphase-promoting complex/cyclosome (apc/c) in complex with cdh1 has an unexpected function in meiosis in that it is essential for meiotic resumption. we identify the catalytic subunit of protein phosphatase 6 (pp6c) as the critical substrate whos ... | 2016 | 26766445 |
| energetics of photoinduced charge migration within the tryptophan tetrad of an animal (6-4) photolyase. | cryptochromes and photolyases are flavoproteins that undergo cascades of electron/hole transfers after excitation of the flavin cofactor. it was recently discovered that animal (6-4) photolyases, as well as animal cryptochromes, feature a chain of four tryptophan residues, while other members of the family contain merely a tryptophan triad. transient absorption spectroscopy measurements on xenopus laevis (6-4) photolyase have shown that the fourth residue is effectively involved in photoreductio ... | 2016 | 26765169 |
| [the biological activity of the sevanol and its analogues]. | previously, from the plant thymus armeniacus a new lignan sevanol was isolated, it's structure was elucidated and was shown that it effectively inhibits the acid-sensing channel asic3 and also exhibits a pronounced analgesic and anti-inflammatory effect. in this work biological activity of the sevanol analog obtained by chemical synthesis from simple precursors, the stereoisomer of sevanol and a precursor molecule represents a half of sevanol was measured in electrophysiological experiments on h ... | 2016 | 26762099 |
| bioelectric signalling via potassium channels: a mechanism for craniofacial dysmorphogenesis in kcnj2-associated andersen-tawil syndrome. | xenopus laevis craniofacial development is a good system for the study of andersen-tawil syndrome (ats)-associated craniofacial anomalies (cfas) because (1) kcnj2 is expressed in the nascent face; (2) molecular-genetic and biophysical techniques are available for the study of ion-dependent signalling during craniofacial morphogenesis; (3) as in humans, expression of variant kcnj2 forms in embryos causes a muscle phenotype; and (4) variant forms of kcnj2 found in human patients, when injected int ... | 2016 | 26864374 |
| stem cell-like xenopus embryonic explants to study early neural developmental features in vitro and in vivo. | understanding the genetic programs underlying neural development is an important goal of developmental and stem cell biology. in the amphibian blastula, cells from the roof of the blastocoel are pluripotent. these cells can be isolated, and programmed to generate various tissues through manipulation of genes expression or induction by morphogens. in this manuscript protocols are described for the use of xenopus laevis blastocoel roof explants as an assay system to investigate key in vivo and in ... | 2016 | 26863402 |
| tweaking subtype selectivity and agonist efficacy at (s)-2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl)propionic acid (ampa) receptors in a small series of bntetampa analogues. | a series of analogues of the (s)-2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl)propionic acid (ampa) receptor agonist bntetampa (5b) were synthesized and characterized pharmacologically in radioligand binding assays at native and cloned ampa receptors and functionally by two-electrode voltage clamp electrophysiology at the four homomeric ampa receptors expressed in xenopus laevis oocytes. the analogues 6 and 7 exhibit very different pharmacological profiles with binding affinity preference for the ... | 2016 | 26862980 |
| unequal contribution of native south african phylogeographic lineages to the invasion of the african clawed frog, xenopus laevis, in europe. | due to both deliberate and accidental introductions, invasive african clawed frog (xenopus laevis) populations have become established worldwide. in this study, we investigate the geographic origins of invasive x. laevis populations in france and portugal using the phylogeographic structure of x. laevis in its native south african range. in total, 80 individuals from the whole area known to be invaded in france and portugal were analysed for two mitochondrial and three nuclear genes, allowing a ... | 2016 | 26855879 |
| a three amino acid deletion in the transmembrane domain of the nicotinic acetylcholine receptor α6 subunit confers high-level resistance to spinosad in plutella xylostella. | spinosad is a macrocyclic lactone insecticide that acts primarily at the nicotinic acetylcholine receptors (nachrs) of target insects. here we describe evidence that high levels of resistance to spinosad in the diamondback moth (plutella xylostella) are associated with a three amino acid (3-aa) deletion in the fourth transmembrane domain (tm4) of the nachr α6 subunit (pxα6). following laboratory selection with spinosad, the sz-spinr strain of p. xylostella exhibited 940-fold resistance to spinos ... | 2016 | 26855198 |
| making muscle: morphogenetic movements and molecular mechanisms of myogenesis in xenopus laevis. | xenopus laevis offers unprecedented access to the intricacies of muscle development. the large, robust embryos make it ideal for manipulations at both the tissue and molecular level. in particular, this model system can be used to fate map early muscle progenitors, visualize cell behaviors associated with somitogenesis, and examine the role of signaling pathways that underlie induction, specification, and differentiation of muscle. several characteristics that are unique to x. laevis include myo ... | 2016 | 26853935 |
| using xenopus laevis retinal and spinal neurons to study mechanisms of axon guidance in vivo and in vitro. | the intricate and precise establishment of neuronal connections in the developing nervous system relies on accurate navigation of growing axons. since ramón y cajal's discovery of the growth cone, the phenomenon of axon guidance has been revealed as a coordinated operation of guidance molecules, receptors, secondary messengers, and responses driven by the dynamic cytoskeleton within the growth cone. with the advent of new and accelerating techniques, xenopus laevis emerged as a robust model to i ... | 2016 | 26853934 |
| heterologous expression of melanopsin: present, problems and prospects. | melanopsin, the photosensory pigment of specialized mammalian retinal ganglion cells, is involved in various non-image forming tasks such as pupillary light reflex, circadian entrainment and irradiance detection. melanopsin genes have been detected in all vertebrate classes and are resolved in two lineages, opn4m and opn4x. in addition, two splice variants have been found in several species leading to a short (opn4-s) and a long (opn4-l) isoform, mainly differing in the length of the c terminus. ... | 2016 | 26850932 |
| a western blot protocol for detection of proteins heterologously expressed in xenopus laevis oocytes. | oocytes of the african clawed frog, xenopus laevis, are often used for expression and biochemical characterization of transporter proteins as the oocytes are particularly suitable for uptake assays and electrophysiological recordings. assessment of the expression level of expressed transporters at the individual oocyte level is often desirable when comparing properties of wild type and mutant transporters. however, a large content of yolk platelets in the oocyte cytoplasm makes this a challengin ... | 2016 | 26843169 |
| rna whole-mount in situ hybridisation proximity ligation assay (rish-pla), an assay for detecting rna-protein complexes in intact cells. | techniques for studying rna-protein interactions have lagged behind those for dna-protein complexes as a consequence of the complexities associated with working with rna. here we present a method for the modification of the existing in situ hybridisation-proximity ligation assay (ish-pla) protocol to adapt it to the study of rna regulation (rish-pla). as proof of principle we used the well-characterised interaction of the xenopus laevis staufen rna binding protein with vg1 mrna, the complex of w ... | 2016 | 26824753 |
| nuclear size is sensitive to ntf2 protein levels in a manner dependent on ran binding. | altered nuclear size is associated with many cancers, and determining whether cancer-associated changes in nuclear size contribute to carcinogenesis necessitates an understanding of mechanisms of nuclear size regulation. although nuclear import rates generally positively correlate with nuclear size, ntf2 levels negatively affect nuclear size, despite the role of ntf2 (also known as nutf2) in nuclear recycling of the import factor ran. we show that binding of ran to ntf2 is required for ntf2 to i ... | 2016 | 26823604 |
| a gradient of maternal bicaudal-c controls vertebrate embryogenesis via translational repression of mrnas encoding cell fate regulators. | vertebrate bicaudal-c (bicc1) has important biological roles in the formation and homeostasis of multiple organs, but direct experiments to address the role of maternal bicc1 in early vertebrate embryogenesis have not been reported. here, we use antisense phosphorothioate-modified oligonucleotides and the host-transfer technique to eliminate specifically maternal stores of both bicc1 mrna and bicc1 protein from xenopus laevis eggs. fertilization of these bicc1-depleted eggs produced embryos with ... | 2016 | 26811381 |
| pld1 regulates xenopus convergent extension movements by mediating frizzled7 endocytosis for wnt/pcp signal activation. | phospholipase d (pld) is involved in the regulation of receptor-associated signaling, cell movement, cell adhesion and endocytosis. however, its physiological role in vertebrate development remains poorly understood. in this study, we show that pld1 is required for the convergent extension (ce) movements during xenopus gastrulation by activating wnt/pcp signaling. xenopus pld1 protein is specifically enriched in the dorsal region of xenopus gastrula embryo and loss or gain-of-function of pld1 in ... | 2016 | 26806705 |
| hmga2 is required for neural crest cell specification in xenopus laevis. | hmga proteins are small nuclear proteins that bind dna by conserved at-hook motifs, modify chromatin architecture and assist in gene expression. two hmgas (hmga1 and hmga2), encoded by distinct genes, exist in mammals and are highly expressed during embryogenesis or reactivated in tumour progression. we here addressed the in vivo role of xenopus hmga2 in the neural crest cells (nccs). we show that hmga2 is required for normal ncc specification and development. hmga2 knockdown leads to severe dis ... | 2016 | 26806704 |