Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| oscillating aquaporin phosphorylation and 14-3-3 proteins mediate the circadian regulation of leaf hydraulics. | the circadian clock regulates plant tissue hydraulics to synchronize water supply with environmental cycles and thereby optimize growth. the circadian fluctuations in aquaporin transcript abundance suggest that aquaporin water channels play a role in these processes. here, we show that hydraulic conductivity (kros) of arabidopsis (arabidopsis thaliana) rosettes displays a genuine circadian rhythmicity with a peak around midday. combined immunological and proteomic approaches revealed that phosph ... | 2019 | 30674691 |
| non-acylated wnts can promote signaling. | wnts are a family of 19 extracellular ligands that regulate cell fate, proliferation, and migration during metazoan embryogenesis and throughout adulthood. wnts are acylated post-translationally at a conserved serine and bind the extracellular cysteine-rich domain (crd) of frizzled (fzd) seven-pass transmembrane receptors. although crystal structures suggest that acylation is essential for wnt binding to fzds, we show here that several wnts can promote signaling in xenopus laevis and danio rerio ... | 2019 | 30673610 |
| effect of the flavonoid hesperidin on glucose and fructose transport, sucrase activity and glycaemic response to orange juice in a crossover trial on healthy volunteers. | although polyphenols inhibit glucose absorption and transport in vitro, it is uncertain whether this activity is sufficient to attenuate glycaemic response in vivo. we examined this using orange juice, which contains high levels of hesperidin. we first used a combination of in vitro assays to evaluate the potential effect of hesperidin and other orange juice components on intestinal sugar absorption and then tested whether this translated to an effect in healthy volunteers. hesperidin attenuated ... | 2019 | 30670104 |
| whole-cell photoacoustic sensor based on pigment relocalization. | photoacoustic (optoacoustic) imaging can extract molecular information with deeper tissue penetration than possible by fluorescence microscopy techniques. however, there is currently still a lack of robust genetically controlled contrast agents and molecular sensors that can dynamically detect biological analytes of interest with photoacoustics. in a biomimetic approach, we took inspiration from cuttlefish who can change their color by relocalizing pigment-filled organelles in so-called chromato ... | 2019 | 30663315 |
| x-linked α-thalassemia with mental retardation is downstream of protein kinase a in the meiotic cell cycle signaling cascade in xenopus oocytes and is dynamically regulated in response to dna damage†. | x-linked α-thalassemia with mental retardation (atrx) is a chromatin remodeling protein that belongs to the switch/sucrose non-fermentable (swi2/snf2) family of helicase/atpases. during meiosis, atrx is necessary for heterochromatin formation and maintenance of chromosome stability in order to ensure proper assembly of the metaphase ii spindle. previously, we established atrx as a novel progesterone regulated protein during bovine meiotic maturation, in addition to being dynamically regulated in ... | 2019 | 30649195 |
| the electrical block to polyspermy induced by an intracellular ca2+ increase at fertilization of the clawed frogs, xenopus laevis and xenopus tropicalis. | polyspermy blocking, to ensure monospermic fertilization, is necessary for normal diploid development in most animals. we have demonstrated here that monospermy in the clawed frog, xenopus tropicalis, as well as in x. laevis, is ensured by a fast, electrical block to polyspermy on the egg plasma membrane after the entry of the first sperm, which is mediated by the positive-going fertilization potential. an intracellular ca2+ concentration ([ca2+ ]i ) at the sperm entry site was propagated as a c ... | 2019 | 30648313 |
| xenopus oocytes as a heterologous expression system for analysis of tight junction proteins. | claudins (cldns) represent the largest family of transmembrane tight junction (tj) proteins, determining organ-specific epithelial barrier properties. because methods for the analysis of multiple cldn interaction are limited, we have established the heterologous xenopus laevis oocyte expression system for tj protein assembly and interaction analysis. oocytes were injected with crna encoding human cldn-1, -2, or -3 or with a combination of these and were incubated in pairs for interaction analysi ... | 2019 | 30645152 |
| insemination or phosphatidic acid induces an outwardly spiraling disk of elevated ca2+ to produce the ca2+ wave during xenopus laevis fertilization. | during xenopus fertilization, the initial intracellular calcium ((ca2+)i) release at the sperm-egg binding site (hot spot) has not been described without the use of inhibitors, nor related to underlying er structure. without inhibitors, we now report that sperm induce an initial hot spot after sperm addition to xenopus eggs that was ~25 µm. this area is consistent with the size of er patches and clusters of ip3 receptors that have enhanced activity. furthermore, we find a new mechanism for the f ... | 2019 | 30641042 |
| deuterium-free, three-plexed peptide diethylation for highly accurate quantitative proteomics. | the deuterium, a frequently used stable isotope in isotopic labeling for quantitative proteomics, could deteriorate the accuracy and precision of proteome quantification owing to the retention time shift of deuterated peptides from the hydrogenated counterpart. we introduce a novel three-plexed peptide "diethylation" using only 13c isotopologues of acetaldehyde and demonstrate that the accuracy and precision of our method in proteome quantification are significantly superior to the conventional ... | 2019 | 30638020 |
| purification and characterization of a urea sensitive lactate dehydrogenase from skeletal muscle of the african clawed frog, xenopus laevis. | the african clawed frog, xenopus laevis endures whole body dehydration which can increase its reliance on anaerobic glycolysis for energy production. this makes the regulation of the terminal enzyme of glycolysis, lactate dehydrogenase (ldh), crucial to stress survival. we investigated the enzymatic properties and posttranslational modification state of purified ldh from the skeletal muscle of control and dehydrated (30% total body water loss) x. laevis. ldh from the muscle of dehydrated frogs s ... | 2019 | 30631901 |
| rhinella marina oocytes: a suitable alternative expression system for functional characterization of aquaglyceroporins. | amphibian oocytes have been extensively used for heterologous expression of membrane proteins for studying their biochemical and biophysical properties. so far, xenopus laevis is the main amphibian used as oocytes source to express aquaglyceroporins in order to assess water and solutes permeability. however, this well-established amphibian model represents a threat to the biodiversity in many countries, especially in those from tropical regions. for that reason, the import of xenopus laevis is s ... | 2019 | 30631140 |
| identification of vacuolar phosphate efflux transporters in land plants. | inorganic phosphate (pi) is an essential component of all life forms. land plants acquire pi from the soil through roots and associated symbioses, and it is then transported throughout the plant. when sufficient, excess pi is stored in vacuoles for remobilization following pi deficiency. although pi release from the vacuoles to the cytoplasm serves as a critical mechanism for plants to adapt to low-pi stress, the transporters responsible for vacuolar pi efflux have not been identified. here, we ... | 2019 | 30626920 |
| ensa and arpp19 differentially control cell cycle progression and development. | greatwall (gwl) is an essential kinase that indirectly controls pp2a-b55, the phosphatase counterbalancing cyclin b/cdk1 activity during mitosis. in xenopus laevis egg extracts, gwl-mediated phosphorylation of overexpressed arpp19 and ensa turns them into potent pp2a-b55 inhibitors. it has been shown that the gwl/ensa/pp2a-b55 axis contributes to the control of dna replication, but little is known about the role of arpp19 in cell division. by using conditional knockout mouse models, we investiga ... | 2019 | 30626720 |
| xenopus slc7a5 is essential for notochord function and eye development. | slc7a5 (also known as lat1), largely accepted as an amino acid transporter, has been shown to play important roles in cancer and developmental processes. because knockout mice of slc7a5 are embryonically lethal due to placental defects, it is difficult to evaluate its role in early development. in this study, expression and function of slc7a5 were evaluated in xenopus laevis embryos that develop without a placenta. expression of slc7a5 was detected in the notochord and in the eye and it was not ... | 2019 | 30625369 |
| reinterpretation of the substrate specificity of the voltage-sensing phosphatase during dimerization. | voltage-sensing phosphatases (vsps) cleave both 3- and 5-phosphates from inositol phospholipids in response to membrane depolarization. when low concentrations of ciona intestinalis vsp are expressed in xenopus laevis oocytes, the 5-phosphatase reaction can be observed during large membrane depolarizations. when higher concentrations are expressed, the 5-phosphatase activity is observed with smaller depolarizations, and the 3-phosphatase activity is revealed with strong depolarization. here we a ... | 2019 | 30622132 |
| probing the dynamics and structural topology of the reconstituted human kcnq1 voltage sensor domain (q1-vsd) in lipid bilayers using electron paramagnetic resonance spectroscopy. | kcnq1 (kv7.1 or kvlqt1) is a potassium ion channel protein found in the heart, ear, and other tissues. in complex with the kcne1 accessory protein, it plays a role during the repolarization phase of the cardiac action potential. mutations in the channel have been associated with several diseases, including congenital deafness and long qt syndrome. nuclear magnetic resonance (nmr) structural studies in detergent micelles and a cryo-electron microscopy structure of kcnq1 from xenopus laevis have s ... | 2019 | 30620191 |
| immunohistochemical localization of calpains in the amphibian xenopus laevis. | though histochemical techniques have been used for decades, they are still very important in basic research. they make it possible to work on fixed tissues and provide a large amount of information in a relatively short time and at a low cost. here we describe methods for indirect immunohistochemistry and immunofluorescence on sections of tadpoles and tissues of adult amphibians belonging to the species xenopus laevis. the objective is to localize calpains within tissues in order to understand t ... | 2019 | 30617797 |
| a stable tetramer is not the only oligomeric state that mitochondrial single-stranded dna binding proteins can adopt. | mitochondrial single-stranded dna (ssdna)-binding proteins (mtssbs) are required for mitochondrial dna replication and stability and are generally assumed to form homotetramers, and this species is proposed to be the one active for ssdna binding. however, we recently reported that the mtssb from saccharomyces cerevisiae (scrim1) forms homotetramers at high protein concentrations, whereas at low protein concentrations, it dissociates into dimers that bind ssdna with high affinity. in this work, u ... | 2019 | 30617184 |
| arid3a regulates nephric tubule regeneration via evolutionarily conserved regeneration signal-response enhancers. | amphibians and fish have the ability to regenerate numerous tissues, whereas mammals have a limited regenerative capacity. despite numerous developmental genes becoming reactivated during regeneration, an extensive analysis is yet to be performed on whether highly regenerative animals utilize unique cis-regulatory elements for the reactivation of genes during regeneration and how such cis-regulatory elements become activated. here, we screened regeneration signal-response enhancers at the lhx1 l ... | 2019 | 30616715 |
| applications of in-cell nmr in structural biology and drug discovery. | in-cell nuclear magnetic resonance (nmr) is a method to provide the structural information of a target at an atomic level under physiological conditions and a full view of the conformational changes of a protein caused by ligand binding, post-translational modifications or protein⁻protein interactions in living cells. previous in-cell nmr studies have focused on proteins that were overexpressed in bacterial cells and isotopically labeled proteins injected into oocytes of xenopus laevis or delive ... | 2019 | 30609728 |
| curare alkaloids from matis dart poison: comparison with d-tubocurarine in interactions with nicotinic, 5-ht3 serotonin and gabaa receptors. | several novel bisbenzylisoquinoline alkaloids (bbiqas) have recently been isolated from a matis tribe arrow poison and shown by two-electrode voltage-clamp to inhibit mouse muscle nicotinic acetylcholine receptors (nachr). here, using radioligand assay with aplysia californica achbp and radioiodinated α-bungarotoxin ([125i]-αbgt), we show that bbiqa1, bbiqa2, and d-tubocurarine (d-tc) have similar affinities to nachr orthosteric site. however, a competition with [125i]-αbgt for binding to the to ... | 2019 | 30608952 |
| skin grafting in xenopus laevis: a technique for assessing development and immunological disparity. | skin grafting in the amphibian xenopus laevis has been used to detect not only allogeneic antigens that differ by minor h antigens or by one mhc haplotype, but also to detect ontogeny-specific antigens (including both emerging adult- and disappearing larval-specific) during metamorphosis. to understand the mechanisms underlying allogeneic tolerance or immune responses against larval- and/or adult-specific antigens, a complete mhc homozygous, inbred strain is the most appropriate experimental mod ... | 2019 | 30606753 |
| methodological improvements for fluorescence recordings in xenopus laevis oocytes. | xenopus laevis oocytes are a widely used model system because of their capacity to translate exogenous mrna, but their high intrinsic background fluorescence is a disadvantage for fluorescence recordings. here, we developed two distinct methods for improving fluorescence recordings from oocytes. one was a pharmacological method in which a small-molecule salt-inducible kinase inhibitor was co-injected with the mrna of interest to stimulate melanin production. we interrogated the oocytes using cut ... | 2019 | 30606741 |
| cdk phosphorylation of xenopus laevis m18bp1 promotes its metaphase centromere localization. | chromosome segregation requires the centromere, the site on chromosomes where kinetochores assemble in mitosis to attach chromosomes to the mitotic spindle. centromere identity is defined epigenetically by the presence of nucleosomes containing the histone h3 variant cenp-a. new cenp-a nucleosome assembly occurs at the centromere every cell cycle during g1, but how cenp-a nucleosome assembly is spatially and temporally restricted remains poorly understood. centromere recruitment of factors requi ... | 2019 | 30606714 |
| the cmg helicase bypasses dna-protein cross-links to facilitate their repair. | covalent dna-protein cross-links (dpcs) impede replication fork progression and threaten genome integrity. using xenopus egg extracts, we previously showed that replication fork collision with dpcs causes their proteolysis, followed by translesion dna synthesis. we show here that when dpc proteolysis is blocked, the replicative dna helicase cmg (cdc45, mcm2-7, gins), which travels on the leading strand template, bypasses an intact leading strand dpc. single-molecule imaging reveals that gins doe ... | 2019 | 30595447 |
| xenopus laevis fgf16 activates the expression of genes coding for the transcription factors sp5 and sp5l. | fibroblast growth factors (fgfs) comprise a family of signalling molecules with essential roles in early embryonic development across animal species. the role of fgfs in mesoderm formation and patterning in xenopus has been particularly well studied. however, little is known about fgf16 in xenopus. using in situ hybridisation, we uncover the expression pattern of fgf16 during early xenopus laevis development, which has not been previously described. we show that the zygotic expression of fgf16 i ... | 2019 | 32149373 |
| a herbivore-induced plant volatile of the host plant acts as a collective foraging signal to the larvae of the meadow moth, loxostege sticticalis (lepidoptera: pyralidae). | the meadow moth loxostege sticticalis is a serious agricultural pest that feeds on the leaves of many economic crops, such as sugar beet, soybean, sunflower, and potato. in addition to the rapid migration of adult moths, the collective foraging behavior of the larvae is also thought to be involved in the search for new food sources and substantially contributes to the expansion of the infested area. however, whether and how the chemical signals take part in this process remains unknown. in this ... | 2019 | 31499032 |
| inferring the "primordial immune complex": origins of mhc class i and antigen receptors revealed by comparative genomics. | comparative analyses suggest that the mhc was derived from a prevertebrate "primordial immune complex" (pic). pic duplicated twice in the well-studied two rounds of genome-wide duplications (2r) early in vertebrate evolution, generating four mhc paralogous regions (predominantly on human chromosomes [chr] 1, 6, 9, 19). examining chiefly the amphibian xenopus laevis, but also other vertebrates, we identified their mhc paralogues and mapped mhc class i, agr, and "framework" genes. most class i gen ... | 2019 | 31492741 |
| pharmacological characterization of a homomeric nicotinic acetylcholine receptor formed by ancylostoma caninum acr-16. | parasitic nematode infections are treated using anthelmintic drugs, some of which target nicotinic acetylcholine receptors (nachrs) located in different parasite tissues. the limited arsenal of anthelmintic agents and the prevalence of drug resistance imply that future defense against parasitic infections will depend on the discovery of novel targets and therapeutics. previous studies have suggested that ascaris suum acr-16 nachrs are a suitable target for the development of antinematodal drugs. ... | 2019 | 31486912 |
| disruptive effects of two organotin pesticides on the thyroid signaling pathway in xenopus laevis during metamorphosis. | organotin compounds are the ubiquitous environmental pollutants due to their wide industrial and agricultural applications and unexpected releasing into the environment, which show characteristic of endocrine disruptors to interfere with the synthesis, receptor binding or action of endogenous-hormones. organotin pesticides (otps) are used in agriculture and may impact endocrine functions on organisms. thyroid hormones (ths) play fundamental roles in regulating the basal metabolism and energy bal ... | 2019 | 31476497 |
| disruption of the lotus japonicus transporter ljnpf2.9 increases shoot biomass and nitrate content without affecting symbiotic performances. | after uptake from soil into the root tissue, distribution and allocation of nitrate throughout the whole plant body, is a critical step of nitrogen use efficiency (nue) and for modulation of plant growth in response to various environmental conditions. in legume plants nitrate distribution is also important for the regulation of the nodulation process that allows to fix atmospheric n (n2) through the symbiotic interaction with rhizobia (symbiotic nitrogen fixation, snf). | 2019 | 31470797 |
| comparative analysis of the developmental toxicity in xenopus laevis and danio rerio induced by al2 o3 nanoparticle exposure. | engineered aluminum oxide nanoparticles (al2 o3 nps) having high-grade thermal stability and water-dispersion properties are extensively used in different industries and personal care products. toxicological response evaluation of these nps is indispensable in assessing the health risks and exposure limits because of their industrial disposal into the aquatic environment. we assessed and compared the developmental toxicity of al2 o3 nps in xenopus laevis and danio rerio over a period of 96 h usi ... | 2019 | 31470468 |
| divergent roles of the wnt/pcp formin daam1 in renal ciliogenesis. | kidneys are composed of numerous ciliated epithelial tubules called nephrons. each nephron functions to reabsorb nutrients and concentrate waste products into urine. defects in primary cilia are associated with abnormal formation of nephrons and cyst formation in a wide range of kidney disorders. previous work in xenopus laevis and zebrafish embryos established that loss of components that make up the wnt/pcp pathway, daam1 and arhgef19 (wgef) perturb kidney tubulogenesis. dishevelled, which act ... | 2019 | 31469868 |
| in cell nmr spectroscopy: investigation of g-quadruplex structures inside living xenopus laevis oocytes. | g-quadruplexes are inherently polymorphic nucleic acid structures. their folding topology depends on the nucleic acid primary sequence and on physical-chemical environmental factors. hence, it remains unclear if a g-quadruplex topology determined in the test tube (in vitro) will also form in vivo. characterization of g-quadruplexes in their native environment has been proposed as an efficient strategy to tackle this issue. so far, characterization of g-quadruplex structures in living cells has r ... | 2019 | 31444765 |
| characterization and proteomic-transcriptomic investigation of monocarboxylate transporter 6 knockout mice: evidence of a potential role in glucose and lipid metabolism. | monocarboxylate transporter 6 [(mct6), slc16a5] is an orphan transporter with no known endogenous substrates or physiological role. previous in vitro and in vivo experiments investigated mct6 substrate/inhibitor specificity in xenopus laevis oocytes; however, these data remain limited. transcriptomic changes in the livers of mice undergoing different dieting schemes have suggested that mct6 plays a role in glucose and lipid metabolism. the objectives of this study were 1) to develop a novel knoc ... | 2019 | 31436537 |
| xenopus laevis as a bioindicator of endocrine disruptors in the region of central chile. | one of the direct causes of biodiversity loss is environmental pollution resulting from the use of chemicals. different kinds of chemicals, such as persistent organic pollutants and some heavy metals, can be endocrine disruptors, which act at low doses over a long period of time and have a negative effect on the reproductive and thyroid system in vertebrates worldwide. research on the effects of endocrine disruptors and the use of bioindicators in neotropical ecosystems where pressure on biodive ... | 2019 | 31422435 |
| changes in ca2+ removal can mask the effects of geometry during ip3r mediated ca2+ signals. | calcium (ca2+) signals are ubiquitous. most intracellular ca2+ signals involve the release of ca2+ from the endoplasmic reticulum (er) through inositol 1,4,5-trisphosphate receptors (ip3rs). the non-uniform spatial organization of ip3rs and the fact that their individual openings are coupled via cytosolic ca2+ are key factors for the variety of spatio-temporal distributions of the cytosolic [ca2+] and the versatility of the signals. in this paper we combine experiments performed in untreated and ... | 2019 | 31417423 |
| gaining insights in the nutritional metabolism of amphibians: analyzing body nutrient profiles of the african clawed frog, xenopus laevis. | whole bodies of xenopus laevis (n = 19) were analysed for chemical composition and morphometrics. the nutrient profile (macronutrients, amino acids, fatty acids and minerals) was evaluated by sex; interactions among variables with body weights and lengths, and comparisons made with different species of marine and fresh water fish. significant differences were found in morphometric measurements, water content, several minerals and fatty acids between sexes of x. laevis. amino acid profiles differ ... | 2019 | 31410305 |
| novel vectors for functional interrogation of xenopus orfeome coding sequences. | the current xenopus orfeome contains ~10,250 validated, full-length cdna sequences without stop codons from xenopus laevis and ~3,970 from xenopus tropicalis cloned into gateway-compatible entry vectors. to increase the utility of the orfeome, we have constructed the gateway-compatible destination vectors pdxtp and pdxtr, which in combination can control the spatial and temporal expression of any open reading frame (orf). pdxtp receives a promoter/enhancer of interest, which controls the spatial ... | 2019 | 31403250 |
| comparative embryonic spatio-temporal expression profile map of the xenopus p2x receptor family. | p2x receptors are atp-gated cations channels formed by the homo or hetero-trimeric association from the seven cloned subunits (p2x1-7). p2x receptors are widely distributed in different organs and cell types throughout the body including the nervous system and are involved in a large variety of physiological but also pathological processes in adult mammals. however, their expression and function during embryogenesis remain poorly understood. here, we report the cloning and the comparative expres ... | 2019 | 31402854 |
| radiographic and ultrasonographic appearance of pneumonia in a frog. | a 12-year-old female african clawed frog (xenopus laevis) displayed lethargy and anorexia for 1 week. radiographs detected a moderately reduced volume of aerated lung with lobulated margins with the left lung predominantly affected. transcelomic ultrasound revealed marked consolidation of the left lung. postmortem examination confirmed suppurative and histiocytic pneumonia, worse in the left lung, caused by mycobacterium chelonae. given that amphibian pulmonary consolidation and celomic effusion ... | 2019 | 31392794 |
| evolution of cis-regulatory modules for the head organizer gene goosecoid in chordates: comparisons between branchiostoma and xenopus. | in cephalochordates (amphioxus), the notochord runs along the dorsal to the anterior tip of the body. in contrast, the vertebrate head is formed anterior to the notochord, as a result of head organizer formation in anterior mesoderm during early development. a key gene for the vertebrate head organizer, goosecoid (gsc), is broadly expressed in the dorsal mesoderm of amphioxus gastrula. amphioxus gsc expression subsequently becomes restricted to the posterior notochord from the early neurula. thi ... | 2019 | 31388442 |
| stereoselective anti-cancer activities of ginsenoside rg3 on triple negative breast cancer cell models. | ginsenoside rg3 (rg3) has two epimers, 20(s)-ginsenoside rg3 (srg3) and 20(r)-ginsenoside rg3 (rrg3), and while rg3 itself has been reported to have anti-cancer properties, few studies have been reported on the anti-cancer effects of the different epimers. the aim was to investigate the stereoselective effects of the rg3 epimers on triple negative breast cancer (tnbc) cell lines, tested using cell-based assays for proliferation, apoptosis, cell cycle arrest, migration and invasion. molecular doc ... | 2019 | 31374984 |
| allocation trade-offs impact organ size and muscle architecture in an invasive population of xenopus laevis in western france. | invasive species are a global scourge and often negatively impact native species. understanding the expansion and dispersal limits of these species is essential. as previous studies have demonstrated increased locomotor performance for populations at the edge of the range of expanding populations, studies of locomotion including the anatomical and physiological traits underlying dispersal capacity are of interest. we focus here on an invasive population of xenopus laevis introduced in france nea ... | 2019 | 31373390 |
| microsampling capillary electrophoresis mass spectrometry enables single-cell proteomics in complex tissues: developing cell clones in live xenopus laevis and zebrafish embryos. | label-free single-cell proteomics by mass spectrometry (ms) is currently incompatible with complex tissues without requiring cell culturing, single-cell dissection, or tissue dissociation. we here report the first example of label-free single-cell ms-based proteomics directly in single cells in live vertebrate embryos. our approach integrates optically guided in situ subcellular capillary microsampling, one-pot extraction-digestion of the collected proteins, peptide separation by capillary elect ... | 2019 | 30827088 |
| conditional demyelination and remyelination in a transgenic xenopus laevis. | multiple sclerosis (ms) is the first cause of acquired disability progression in the young adult. pathology of ms associates inflammation, demyelination, and neurodegeneration. the development of immunotherapies, by reducing the relapse rate, has profoundly impacted short-term prognosis and patients' quality of life. these anti-inflammatory medications, however, have not proven to be sufficient to prevent long-term disability progression, resulting from axonal transection and neuronal damage, co ... | 2019 | 30820903 |
| the c-terminus of the retinal homeobox (rax) gene product modulates transcription in a context-dependent manner. | the evolutionarily conserved retinal homeobox (rax) transcription factor is essential for normal eye development in all vertebrates. despite rax's biologic significance, the molecular mechanisms underlying rax molecular function as a transcriptional regulator are poorly defined. the rax gene encodes a conserved octapeptide motif (op) near the n-terminus and several conserved regions in the c-terminus of unknown function, including the orthopedia, aristaless, rax (oar) domain and the rx domain. t ... | 2019 | 30820152 |
| more than just a bandage: closing the gap between injury and appendage regeneration. | the remarkable regenerative capabilities of amphibians have captured the attention of biologists for centuries. the frogs xenopus laevis and xenopus tropicalis undergo temporally restricted regenerative healing of appendage amputations and spinal cord truncations, injuries that are both devastating and relatively common in human patients. rapidly expanding technological innovations have led to a resurgence of interest in defining the factors that enable regenerative healing, and in coupling thes ... | 2019 | 30800076 |
| the wnt inhibitor dkk1 is required for maintaining the normal cardiac differentiation program in xenopus laevis. | wnt proteins can activate different intracellular signaling pathways. these pathways need to be tightly regulated for proper cardiogenesis. the canonical wnt/β-catenin inhibitor dkk1 has been shown to be sufficient to trigger cardiogenesis in gain-of-function experiments performed in multiple model systems. loss-of-function studies however did not reveal any fundamental function for dkk1 during cardiogenesis. using xenopus laevis as a model we here show for the first time that dkk1 is required f ... | 2019 | 30797757 |
| fluorescent analogues of bekm-1 with high and specific activity against the herg channel. | peptidic toxins that target specifically mammalian channels and receptors can be found in the venom of animals. these toxins are rarely used directly as tools for biochemical experiments, and need to be modified via the attachment of chemical groups (e.g., radioactive or fluorescent moieties). ideally, such modifications should maintain the toxin specificity and affinity for its target. with the goal of obtaining fluorescent derivatives of bekm-1, a toxin from the scorpion species buthus eupeus ... | 2019 | 32550567 |
| rho flares repair local tight junction leaks. | tight junctions contribute to epithelial barrier function by selectively regulating the quantity and type of molecules that cross the paracellular barrier. experimental approaches to evaluate the effectiveness of tight junctions are typically global, tissue-scale measures. here, we introduce zinc-based ultrasensitive microscopic barrier assay (znumba), which we used in xenopus laevis embryos to visualize short-lived, local breaches in epithelial barrier function. these breaches, or leaks, occur ... | 2019 | 30773490 |
| activity and intracellular localization of senescence-associated β-galactosidase in aging xenopus oocytes and eggs. | senescence-associated β-galactosidase (sa-β-gal) serves as a marker of senescence in aging somatic cells. however, little is known about sa-β-gal dynamics in aging gamete cells. to address this issue, here we investigated activity and intracellular localization of sa-β-gal in freshly obtained and aging oocytes and eggs of the african clawed frog xenopus laevis. data base mining revealed the presence of several homologous β-galactosidase sequences in the annotated xenopus genome. some of them wer ... | 2019 | 30769028 |
| on the mechanism of the electrophysiological changes and membrane lesions induced by asbestos fiber exposure in xenopus laevis oocytes. | the so-called amphibole asbestos fibers are enriched with mineral iron ions, able to stimulate ros production. we recently reported that crocidolite asbestos was able to interact with the cell membranes of xenopus laevis oocytes, to alter their electrical membrane properties. here, we found that applied iron ions (fe3+) or h2o2 (for ros generation) mimicked these effects, suggesting that at least one effect of iron-containing asbestos fiber exposure was mediated by ros production. furthermore, c ... | 2019 | 30765791 |
| wgddetector: a pipeline for detecting whole genome duplication events using the genome or transcriptome annotations. | with the availability of well-assembled genomes of a growing number of organisms, identifying the bioinformatic basis of whole genome duplication (wgd) is a growing field of genomics. the most extant software for detecting footprints of wgds has been restricted to a well-assembled genome. however, the massive poor quality genomes and the more accessible transcriptomes have been largely ignored, and in theoretically they are also likely to contribute to detect wgd using ds based method. here, to ... | 2019 | 30760221 |
| various nuclear reprogramming systems using egg and oocyte materials. | maternal factors stored in eggs and oocytes are necessary for reprogramming sperm for embryonic development. this reprogramming activity of maternal factors also works towards somatic cells, including terminally differentiated cells. several different experimental systems utilizing egg and oocyte materials have been applied to study nuclear reprogramming by maternal factors. among these systems, the most widely used is the transfer of a somatic cell nucleus to an oocyte arrested at the metaphase ... | 2019 | 30745498 |
| pymetrozine activates trpv channels of brown planthopper nilaparvata lugens. | the commercial insecticide pymetrozine has been extensively used for brown planthopper control in east asia. the transient receptor potential vanilloid (trpv) channel, which consists of two proteins, nanchung (nan) and inactive (iav), has recently been shown to be the molecular target of pymetrozine in the fruit fly (drosophila melanogaster) and pea aphid (acyrthosiphon pisum). in this study, we characterized the nan and iav trpv channel subunits of n. lugens and measured the action of pymetrozi ... | 2019 | 30744899 |
| jaburetox, a natural insecticide derived from jack bean urease, activates voltage-gated sodium channels to modulate insect behavior. | jaburetox (jbtx) is an insecticidal peptide derived from canavalia ensiformis urease, whose mechanism of action is not completely elucidated. we employed behavioral, electromyographical and electrophysiological protocols to identify the cellular and molecular targets involved in the jbtx entomotoxicity in cockroaches and locusts. in nauphoeta cinerea, jbtx (32 μg/g) altered the locomotory behaviour inducing a significative decrease in the distance travelled followed by a significant increase in ... | 2019 | 30744898 |
| gene expression program underlying tail resorption during thyroid hormone-dependent metamorphosis of the ornamented pygmy frog microhyla fissipes. | thyroid hormone (t3) is essential for vertebrate development, especially during the so-called postembryonic development, a period around birth in mammals when plasma t3 level peaks and many organs mature into their adult form. compared to embryogenesis, postembryonic development is poorly studied in mammals largely because of the difficulty to manipulate the uterus-enclosed embryos and neonates. amphibian metamorphosis is independent of maternal influence and can be easily manipulated for molecu ... | 2019 | 30740088 |
| generation of xenopus haploid, triploid, and hybrid embryos. | frog species of the genus xenopus are widely used for studies of cell and developmental biology, and recent genome sequencing has revealed interesting phylogenetic relationships. here we describe methods to generate haploid, triploid, and hybrid species starting from eggs and sperm of xenopus laevis and xenopus tropicalis that enable investigation of how genome size and content affect physiology at the organismal, cellular, and subcellular levels. | 2019 | 30737699 |
| methods for isolating the balbiani body/germplasm from xenopus laevis oocytes. | the balbiani body (bb) is a large membrane-less organelle, densely packed with mitochondria, endoplasmic reticulum, proteins, and rna. the bb is present in many vertebrate female gametes. in frogs, the bb is established early during oogenesis and operates as a maternal inherited embryonic determinant that specifies germline identity through the formation of germplasm. we describe here two techniques to isolate the bb/germplasm from xenopus laevis primary oocytes. | 2019 | 30737696 |
| membrane microdomains as platform to study membrane-associated events during oogenesis, meiotic maturation, and fertilization in xenopus laevis. | studies on the egg plasma membrane-associated tyrosine kinase src have shed light on the identity of the molecular machinery that is responsible for gamete interaction and possibly fusion in african clawed frog xenopus laevis. here we describe our protocol for identifying and analyzing molecular and cellular machinery that contributes to a variety of biological processes in the course of oogenesis, oocyte maturation, egg fertilization, and early embryogenesis in xenopus. our current special inte ... | 2019 | 30737686 |
| reconstitution of intracellular calcium signaling in xenopus egg extracts. | generation of calcium signal in the cytoplasm of fertilized or parthenogenetically activated eggs has been extensively studied in the intact eggs of several biological species. calcium transient was found to elicit a plethora of biochemical and cellular events in these cells. remarkably, intracellular calcium signaling can also be reconstituted in cell-free environment. in this chapter, we describe the methods that allow reconstitution, detection, and quantification of the calcium signal in cell ... | 2019 | 30737685 |
| imatinib uptake into cells is not mediated by organic cation transporters oct1, oct2, or oct3, but is influenced by extracellular ph. | cancer cells undergo genetic and environmental changes that can alter cellular disposition of drugs, notably by alterations of transmembrane drug transporters expression. whether the influx organic cation transporter 1 (oct1) encoded by the gene slc221a1 is implicated in the cellular uptake of imatinib is still controversial. besides, imatinib ionization state may be modulated by the hypoxic acidic surrounding extracellular microenvironment. | 2019 | 30734690 |
| comparison the sensitivity of amphibian metamorphosis assays with nf 48 stage and nf 51 stage xenopus laevis tadpoles. | the amphibian metamorphosis assay (ama) was proposed by the organization for economic cooperation and development (oecd) to screen thyroid disruptors of vertebrate species. the general experimental design of the ama exposes nieuwkoop and faber (nf) stage 51 xenopus laevis tadpoles to test chemical concentrations for 21 d. however, recent studies demonstrated that thyroid gland began to function after nf stage 45 in x. laevis. thus, in this study, we initiated exposure with nf stage 48 tadpoles w ... | 2019 | 30732517 |
| using xenopus laevis oocytes to functionally characterize plant transporters. | functionally characterizing plant membrane transport proteins is challenging. typically, heterologous systems are used to study them. immature eggs (oocytes) of the south african clawed frog xenopus laevis are considered an ideal expression system for such studies. these large oocytes have a low number of endogenous transport systems in their plasma membranes and highly express foreign mrna; the oocyte plasma membrane is the default destination of integral membrane proteins that lack recognized ... | 2019 | 30707001 |
| anillin regulates epithelial cell mechanics by structuring the medial-apical actomyosin network. | cellular forces sculpt organisms during development, while misregulation of cellular mechanics can promote disease. here, we investigate how the actomyosin scaffold protein anillin contributes to epithelial mechanics in xenopus laevis embryos. increased mechanosensitive recruitment of vinculin to cell-cell junctions when anillin is overexpressed suggested that anillin promotes junctional tension. however, junctional laser ablation unexpectedly showed that junctions recoil faster when anillin is ... | 2019 | 30702429 |
| αd-conotoxins in species of the eastern pacific: the case of conus princeps from mexico. | conus snails produce venoms containing numerous peptides such as the α-conotoxins (α-ctxs), which are well-known nicotinic acetylcholine receptor (nachr) antagonists. thirty-eight chromatographic fractions from conus princeps venom extract were isolated by rp-hplc. the biological activities of 37 fractions (0.07 µg/µl) were assayed by two-electrode voltage clamp on human α7 nachrs expressed in xenopus laevis oocytes. fractions f7 and f16 notably inhibited the response elicited by acetylcholine b ... | 2019 | 31336928 |
| reference gene validation for quantitative real-time pcr studies in amphibian kidney-derived a6 epithelial cells. | quantitative real-time polymerase chain reaction is a widely used technique that relies on reference genes for the normalisation of gene expression. these reference genes are constitutively expressed and must remain stable across all samples and treatments. stability of housekeeping genes may vary and must be optimised for a specific tissue, sample or cell line. here we present a study screening for possible reference gene candidates, eef1a1, rpl8, sub1.l, clta, h4 and odc1, in the xenopus laevi ... | 2019 | 31333044 |
| involvement of g-quadruplex regions in mammalian replication origin activity. | genome-wide studies of dna replication origins revealed that origins preferentially associate with an origin g-rich repeated element (ogre), potentially forming g-quadruplexes (g4). here, we functionally address their requirements for dna replication initiation in a series of independent approaches. deletion of the ogre/g4 sequence strongly decreased the corresponding origin activity. conversely, the insertion of an ogre/g4 element created a new replication origin. this element also promoted rep ... | 2019 | 31332171 |
| na3 glycan: a potential therapy for retinal pigment epithelial deficiency. | atrophic age-related macular degeneration (amd) is the most common type of amd, yet there is no united states food and drug administration (fda)-approved therapy. this disease is characterized by retinal pigment epithelial (rpe) insufficiency, primarily in the macula, which affects the structure and physiology of photoreceptors and ultimately, visual function. in this study, we evaluated the protective effects of a naturally derived small molecule glycan therapeutic-asialo-, tri-antennary comple ... | 2019 | 31322324 |
| structure, development, and functional morphology of the cement gland of the giant danio, devario malabaricus. | aquatic species in several clades possess cement glands producing adhesive secretions of various strengths. in vertebrates, transient adhesive organs have been extensively studied in xenopus laevis, other anurans, and in several fish species. however, the development of these structures is not fully understood. | 2019 | 31310039 |
| evaluating the role of fish as surrogates for amphibians in pesticide ecological risk assessment. | ecological risk of chemicals to aquatic-phase amphibians has historically been evaluated by comparing estimated environmental concentrations in surface water to surrogate toxicity data from fish species. despite their obvious similarities, there are biological disparities among fish and amphibians that could affect their exposure and response to chemicals. given the alarming decline in amphibians, in which anthropogenic pollutants play at least some role, investigating the risk of chemicals to a ... | 2019 | 31299708 |
| the many faces of xenopus: xenopus laevis as a model system to study wolf-hirschhorn syndrome. | wolf-hirschhorn syndrome (whs) is a rare developmental disorder characterized by intellectual disability and various physical malformations including craniofacial, skeletal, and cardiac defects. these phenotypes, as they involve structures that are derived from the cranial neural crest, suggest that whs may be associated with abnormalities in neural crest cell (ncc) migration. this syndrome is linked with assorted mutations on the short arm of chromosome 4, most notably the microdeletion of a cr ... | 2019 | 31297068 |
| phosphomimetic substitution at ser-33 of the chloroquine resistance transporter pfcrt reconstitutes drug responses in plasmodium falciparum. | the chloroquine resistance transporter pfcrt of the human malaria parasite plasmodium falciparum confers resistance to the former first-line antimalarial drug chloroquine, and it modulates the responsiveness to a wide range of quinoline and quinoline-like compounds. pfcrt is post-translationally modified by phosphorylation, palmitoylation, and, possibly, ubiquitination. however, the impact of these post-translational modifications on p. falciparum biology and, in particular, the drug resistance- ... | 2019 | 31285265 |
| assessing predator-prey interactions in a chemically altered aquatic environment: the effects of ddt on xenopus laevis and culex sp. larvae interactions and behaviour. | behavioural assays are used as a tool to understand ecotoxicological effects on organisms, but are often not applied in an ecologically relevant context. assessment of the effect of chemical contaminants on behaviours relating to fitness and trophic interactions for example, requires incorporating predator-prey interactions to create impact assessments. dichlorodiphenyltrichloroethane (ddt) is a controlled substance but is still regularly used as a form of mosquito control. there is little expli ... | 2019 | 31278447 |
| effects of cis-bifenthrin enantiomers on the growth, behavioral, biomarkers of oxidative damage and bioaccumulation in xenopus laevis. | chirality should be taken into consideration when assessing the effect of synthetic pyrethroids to aquatic environmental safety. in our study, 96 h acute toxicity assay showed that enantiomers of cis-bf had an addictive effect of toxicity on xenopus laevis and r-cis-bifenthrin(r-cis-bf) had higher acute toxicity than s-cis-bf. in chronic assay, r-cis-bf exerted more toxic effect on behavior and development of tadpoles than s-cis-bf, and there was also enantioselective effect of cis-bf on antioxi ... | 2019 | 31276910 |
| neuroendocrine modulation of predator avoidance/prey capture tradeoffs: role of tectal npy2r receptors. | the optic tectum rapidly inhibits food intake when a visual threat is present. anatomical and electrophysiological evidence support a role for neuropeptide y (npy), originating from cells in the thalamus, in the tectal inhibition of prey capture. here we test the hypothesis that tectal npy receptor type 2 (npy2r) influences prey-capture and predator-avoidance responses in the african clawed frog, xenopus laevis. we tested two questions: 1) does tectal npy administration decrease food intake and ... | 2019 | 31271760 |
| impact of 4-aminopyridine on vestibulo-ocular reflex performance. | vestibulo-ocular reflexes (vor) are mediated by frequency-tuned pathways that separately transform the different dynamic and static aspects of head motion/position-related sensory signals into extraocular motor commands. voltage-dependent potassium conductances such as those formed by kv1.1 are important for the ability of vor circuit elements to encode highly transient motion components. here we describe the impact of the kv1.1 channel blocker 4-aminopyridine (4-ap) on spontaneous and motion-ev ... | 2019 | 31270663 |
| impacts of the synthetic androgen trenbolone on gonad differentiation and development - comparisons between three deeply diverged anuran families. | using a recently developed approach for testing endocrine disruptive chemicals (edcs) in amphibians, comprising synchronized tadpole exposure plus genetic and histological sexing of metamorphs in a flow-through-system, we tested the effects of 17β-trenbolone (tb), a widely used growth promoter in cattle farming, in three deeply diverged anuran families: the amphibian model species xenopus laevis (pipidae) and the non-models bufo(tes) viridis (bufonidae) and hyla arborea (hylidae). trenbolone was ... | 2019 | 31270347 |
| developmentally regulated gtp-binding protein 1 modulates ciliogenesis via an interaction with dishevelled. | cilia are critical for proper embryonic development and maintaining homeostasis. although extensively studied, there are still significant gaps regarding the proteins involved in regulating ciliogenesis. using the xenopus laevis embryo, we show that dishevelled (dvl), a key wnt signaling scaffold that is critical to proper ciliogenesis, interacts with drg1 (developmentally regulated gtp-binding protein 1). the loss of drg1 or disruption of the interaction with dvl reduces the length and number o ... | 2019 | 31270137 |
| phosphatidylinositol 4,5-bisphosphate (pip2) and ca2+ are both required to open the cl- channel tmem16a. | transmembrane member 16a (tmem16a) is a widely expressed ca2+-activated cl- channel with various physiological functions ranging from mucosal secretion to regulating smooth muscle contraction. understanding how tmem16a controls these physiological processes and how its dysregulation may cause disease requires a detailed understanding of how cellular processes and second messengers alter tmem16a channel gating. here we assessed the regulation of tmem16a gating by recording ca2+-evoked cl- current ... | 2019 | 31266809 |
| dyrk1a-related intellectual disability: a syndrome associated with congenital anomalies of the kidney and urinary tract. | haploinsufficiency of dyrk1a causes a recognizable clinical syndrome. the goal of this paper is to investigate congenital anomalies of the kidney and urinary tract (cakut) and genital defects (gd) in patients with dyrk1a variants. | 2019 | 31263215 |
| functional characterization of smn evolution in mouse models of sma. | spinal muscular atrophy (sma) is a monogenic neurodegenerative disorder and the leading genetic cause of infantile mortality. while several functions have been ascribed to the smn (survival motor neuron) protein, their specific contribution to the disease has yet to be fully elucidated. we hypothesized that some, but not all, smn homologues would rescue the sma phenotype in mouse models, thereby identifying disease-relevant domains. using aav9 to deliver smn homologs to sma mice, we identified a ... | 2019 | 31263170 |
| comparative analysis of p4ha1 and p4ha2 expression during xenopus laevis development. | collagen prolyl 4-hydroxylases (c-p4hs) are evolutionary conserved enzymes whose activity is essential for the correct folding of stable triple helical molecules of collagen and collagen-like proteins. they play crucial roles in embryo development, connective tissue functional organization, tumor growth and metastasis. despite the important function of these enzymes, little is known about their expression during vertebrate development. in this study, we determine and compare the previously undes ... | 2019 | 31250915 |
| transcriptome analysis of regeneration during xenopus laevis experimental twinning. | animal embryos have the remarkable property of self-organization. over 125 years ago, hans driesch separated the two blastomeres of sea urchin embryos and obtained twins, in what was the foundation of experimental embryology. since then, embryonic twinning has been obtained experimentally in many animals. in a recent study, we developed bisection methods that generate identical twins reliably from xenopus blastula embryos. in the present study, we have investigated the transcriptome of regenerat ... | 2019 | 31250914 |
| data demonstrating distinct embryonic developmental defects induced by bisphenol a alternatives. | embryos of xenopus laevis (african clawed frog) were exposed to the widespread environmental plasticizers bisphenol af (bpaf; 0.003-3 μm), bisphenol a (bpa; 1-50 μm), or 17β-estradiol (e2; 10 μm) from just after fertilization through 96 hours of development. the potencies and cellular and morphological effects were compared across chemical treatments and controls. the embryos were staged, counted and imaged, and time-lapse movies collected, on an inverted stereomicroscope and camera. the data sh ... | 2019 | 31249853 |
| an extracellular acidic cleft confers profound h+-sensitivity to epithelial sodium channels containing the δ-subunit in xenopus laevis. | the limited sodium availability of freshwater and terrestrial environments was a major physiological challenge during vertebrate evolution. the epithelial sodium channel (enac) is present in the apical membrane of sodium-absorbing vertebrate epithelia and evolved as part of a machinery for efficient sodium conservation. enac belongs to the degenerin/enac protein family and is the only member that opens without an external stimulus. we hypothesized that enac evolved from a proton-activated sodium ... | 2019 | 31248986 |
| commentary on classic paper "gimlich, r.l., gerhart, j.c., 1984. early cellular interactions promote embryonic axis formation in xenopus laevis. dev biol 104, 117-130." | 2019 | 31235010 | |
| catalyst-free click pegylation reveals substantial mitochondrial atp synthase sub-unit alpha oxidation before and after fertilisation. | using non-reducing western blotting to assess protein thiol redox state is challenging because most reduced and oxidised forms migrate at the same molecular weight and are, therefore, indistinguishable. while copper catalysed click chemistry can be used to ligate a polyethylene glycol (peg) moiety termed click pegylation to mass shift the reduced or oxidised form as desired, the potential for copper catalysed auto-oxidation is problematic. here we define a catalyst-free trans-cyclooctene-methylt ... | 2019 | 31234016 |
| cardiotoxicity in african clawed frog (xenopus laevis) sub-chronically exposed to environmentally relevant atrazine concentrations: implications for species survival. | the toxic effects of different atrazine concentrations on tadpoles and adult male african clawed frogs (xenopus laevis) were assessed in a controlled laboratory environment following 90 days' exposure. the aim was to elucidate the danger of atrazine exposure on the cardiac tissue relative to its critical function of rhythmic contractility, fundamental for optimal blood circulation and homeostasis. tadpoles and adult frogs were exposed to 0 μg/l (control), 0.01 μg l-1, 200 μg l-1 and 500 μg l-1 c ... | 2019 | 31203168 |
| peia-5466: a novel peptide antagonist containing non-natural amino acids that selectively targets α3β2 nicotinic acetylcholine receptors. | pharmacologically distinguishing α3β2 nicotinic acetylcholine receptors (nachrs) from closely related subtypes, particularly α6β2, has been challenging due to the lack of subtype-selective ligands. we created analogs of α-conotoxin (α-ctx) peia to identify ligand-receptor interactions that could be exploited to selectively increase potency and selectivity for α3β2 nachrs. a series of peia analogs were synthesized by replacing amino acid residues in the second disulfide loop with standard or nons ... | 2019 | 31194549 |
| single cell proteomics by data-independent acquisition to study embryonic asymmetry in xenopus laevis. | techniques that allow single cell analysis are gaining widespread attention, and most of these studies utilize genomics-based approaches. while nanofluidic technologies have enabled mass spectrometric analysis of single cells, these measurements have been limited to metabolomics and lipidomic studies. single cell proteomics has the potential to improve our understanding of intercellular heterogeneity. however, this approach has faced challenges including limited sample availability, as well as a ... | 2019 | 31194517 |
| injection of mrna isolated from trophozoites of giardia intestinalis induces expression of three types of chloride currents in xenopus laevis oocytes. | giardia lamblia is one of the most important worldwide causes of intestinal infections, yet little is known about its cellular physiology, especially the diversity of ionic channels that this parasite expresses. in this work, we show that injection of mrna isolated from trophozoites of giardia, into xenopus laevis oocytes, induces expression of three types of chloride currents (here referred to as icl-g1, icl-g2, and icl-g3), which have different biophysical and pharmacological properties. icl-g ... | 2019 | 31187589 |
| the effect of xenopus laevis egg extracts with/without brg1 on the development of preimplantation cloned mouse embryos. | summarymuch effort has been devoted to improving the efficiency of animal cloning. the aim of this study was to investigate the effect of brg1 contained in xenopus egg extracts on the development of cloned mouse embryos. the results showed that mouse nih/3t3 cells were able to express pluripotent genes after treatment with egg extracts, indicating that the egg extracts contained reprogramming factors. after co-injection of xenopus egg extracts and single mouse cumulus cells into enucleated mouse ... | 2019 | 31182178 |
| dspe-peg modification of α-conotoxin txid. | in order to improve stability of a peptide marine drug lead, α-conotoxin txid, we synthesized and modified txid at the n-terminal with dspe-peg-nhs by a nucleophilic substitution reaction to prepare the dspe-peg-txid for the first time. the reaction conditions, including solvent, ratio, ph, and reaction time, were optimized systematically and the optimal one was reacted in dimethyl formamide at ph 8.2 with triethylamine at room temperature for 120 h. the in vitro stabilities in serum, simulated ... | 2019 | 31181805 |
| ecotoxicity of nanomaterials in amphibians: a critical review. | nanomaterials (nms) have been used in a growing number of commercial products, and their rapid expansion could lead to their release into the aquatic environments. however, there is limited knowledge about the impact of nms in the biota, especially the amphibians. the present study revised the historical use of amphibian species as a model system for nanoecotoxicological studies and summarized the data available in the scientific literature about the genotoxic, mutagenic, histopathological, embr ... | 2019 | 31181520 |
| disassembly of actin and keratin networks by aurora b kinase at the midplane of cleaving xenopus laevis eggs. | the large length scale of xenopus laevis eggs facilitates observation of bulk cytoplasm dynamics far from the cortex during cytokinesis. the first furrow ingresses through the egg midplane, which is demarcated by chromosomal passenger complex (cpc) localized on microtubule bundles at the boundary between asters. using an extract system, we found that local kinase activity of the aurora b kinase (aurkb) subunit of the cpc caused disassembly of f-actin and keratin between asters and local softenin ... | 2019 | 31178324 |
| organic anion-transporting polypeptide 1a4-mediated heterogeneous distribution of sulforhodamine-101 in rat hepatic lobules. | it has been known that organic anion-transporting polypeptides (oatps) involve hepatic transports several organic anionic compounds and drugs. this study aimed to investigate sulforhodamine-101 (sr-101) distribution in the rat liver, determine the molecules responsible for the distribution, and delineate the manner of distribution. after intravenous sr-101 administration, its distribution in frozen rat hepatic sections was examined. sr-101-derived signals were detected in regions around the hepa ... | 2019 | 31174976 |
| a sclerocornea-associated rad21 variant induces corneal stroma disorganization. | sclerocornea is a cornea opacification disorder. disorganized corneal stroma fibrils are observed in patients' cornea. previously we identified a rad21c1348t variant that is associated with a peripheral sclerocornea pedigree. to explore whether this rad21 variant can induce sclerocornea-related phenotype, and to investigate the possible mechanisms of such phenotype, the orthologous rad21 wild-type and variant mrnas were injected into xenopus laevis embryos and the developed eyes were subjected f ... | 2019 | 31173765 |
| ism1 regulates nodal signaling and asymmetric organ morphogenesis during development. | isthmin1 (ism1) was originally identified as a fibroblast group factor expressed in xenopus laevis embryonic brain, but its biological functions remain unclear. the spatiotemporal distribution of ism1, with high expression in the anterior primitive streak of the chick embryo and the anterior mesendoderm of the mouse embryo, suggested that ism1 may regulate signaling by the nodal subfamily of tgb-β cytokines that control embryo patterning. we report that ism1 is an inhibitor of nodal signaling. i ... | 2019 | 31171630 |