Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| involvement of myt1 kinase in the g2 phase of the first cell cycle in xenopus laevis. | during cleavage of xenopus laevis, the first mitotic cell cycle immediately following fertilization is approximately 90 min and consists of s, g2, and m phases. in contrast, the subsequent eleven cell cycles are approximately 30 min and consist mostly of s and m phases. the balance between cdc25 and wee1a/myt1 is thought to be crucial for xenopus first cell cycle progression; however, the role of myt1 in this period has not been fully investigated. in this study, we examined the roles of myt1, w ... | 2019 | 31128913 |
| methods for studying dna single-strand break repair and signaling in xenopus laevis egg extracts. | dna single-strand breaks (ssbs) are the most common type of dna lesions as they are generated approximately 10,000 times per mammalian cell each day. unrepaired ssbs compromise dna replication and transcription programs, leading to genome instability, and have been implicated in many diseases including cancer. in this chapter, we introduce methods to study the atr-chk1 dna damage response (ddr) pathway and dna repair pathway in response to a site-specific, defined ssb plasmid in xenopus laevis e ... | 2019 | 31127575 |
| ptk7 proteolytic fragment proteins function during early xenopus development. | protein tyrosine kinase 7 (ptk7) is as a critical regulator of canonical and non-canonical wnt-signaling during embryonic development and cancer cell formation. disrupting ptk7 activity perturbs vertebrate nervous system development, and also promotes human cancer formation. observations in different model systems suggest a complex cross-talk between ptk7 protein and wnt signaling. during xenopus laevis nervous system development, we previously showed that ptk7 protein positively regulates canon ... | 2019 | 31125531 |
| development of an in vitro diagnostic method to determine the genotypic sex of xenopus laevis. | a genotypic sex determination assay provides accurate gender information of individuals with well-developed phenotypic characters as well as those with poorly developed or absent of phenotypic characters. determination of genetic sex for xenopus laevis can be used to validate the outcomes of tier 2 amphibian assays, and is a requirement for conducting the larval amphibian growth and development assay (lagda), in the endocrine disruptor screening program (edsp), test guidelines. the assay we deve ... | 2019 | 31106075 |
| composition and endocrine effects of water collected in the kibale national park in uganda. | pesticides are used worldwide with potential harmful effects on both fauna and flora. the kibale national park in uganda, a site renowned for its biodiversity is surrounded by tea, banana and eucalyptus plantations as well as maize fields and small farms. we previously showed presence of pesticides with potential endocrine disruptive effects in the vicinity. to further investigate the water pollution linked to agricultural pressure in this protected area, we implemented a complementary monitorin ... | 2019 | 31103006 |
| identification of a regeneration-organizing cell in the xenopus tail. | unlike mammals, xenopus laevis tadpoles have a high regenerative potential. to characterize this regenerative response, we performed single-cell rna sequencing after tail amputation. by comparing naturally occurring regeneration-competent and -incompetent tadpoles, we identified a previously unrecognized cell type, which we term the regeneration-organizing cell (roc). rocs are present in the epidermis during normal tail development and specifically relocalize to the amputation plane of regenerat ... | 2019 | 31097661 |
| embryonic expression of gins members in the development of the mammalian nervous system. | the gins (go, ichi, nii, and san) complex contains four protein subunits (psf1, psf2, psf3, and sld5) and has been identified as a factor essential for the initiation and elongation stages of the dna replication process. a previous study indicated that psf2 participated in the developing central nervous system (cns) of xenopus laevis. however, the expression and function of gins members in the mammalian developing nervous system remains unclear. here, we examined the expression of gins members i ... | 2019 | 31095979 |
| spindle-f-actin interactions in mitotic spindles in an intact vertebrate epithelium. | mitotic spindles are well known to be assembled from and dependent on microtubules. in contrast, whether actin filaments (f-actin) are required for or are even present in mitotic spindles has long been controversial. here we have developed improved methods for simultaneously preserving f-actin and microtubules in fixed samples and exploited them to demonstrate that f-actin is indeed associated with mitotic spindles in intact xenopus laevis embryonic epithelia. we also find that there is an "f-ac ... | 2019 | 31091161 |
| neurotoxicity and mode of action of fluralaner on honeybee apis mellifera l. | fluralaner, a novel pesticide that targets the γ-aminobutyric acid (gaba) receptor (gabar) subunit of resistant to dieldrin (rdl), exhibits strong potential to be an insecticide to control agricultural insect pests. however, the risk and action of fluralaner to economic insects, e.g., honeybee apis mellifera linnaeus, remains unclear. | 2019 | 31081291 |
| xenopus resources: transgenic, inbred and mutant animals, training opportunities, and web-based support. | two species of the clawed frog family, xenopus laevis and x. tropicalis, are widely used as tools to investigate both normal and disease-state biochemistry, genetics, cell biology, and developmental biology. to support both frog specialist and non-specialist scientists needing access to these models for their research, a number of centralized resources exist around the world. these include centers that hold live and frozen stocks of transgenic, inbred and mutant animals and centers that hold mol ... | 2019 | 31073289 |
| pdgf-b: the missing piece in the mosaic of pdgf family role in craniofacial development. | the platelet-derived growth factor (pdgf) family consists of four ligands (pdgf-a, pdgf-b, pdgf-c, pdgf-d) and two tyrosine kinase receptors (pdgfr-α and pdgfr-β). in vertebrates, pdgf signaling influences cell proliferation, migration, and matrix deposition, and its up-regulation is implicated in cancer progression. despite this evidence, the role of each family member during embryogenesis is still incomplete and partially controversial. in particular, study of the role of pdgf signaling during ... | 2019 | 31070827 |
| the xenopus tropicalis model for studies of developmental and reproductive toxicity. | the reproductive cycle encompasses processes such as sex organ differentiation and development in the early life stages and maturation of the gametes in the adult organism. during the early life stages, critical developmental programming of the endocrine and reproductive systems occurs, and exposure to chemicals during these critical developmental windows can result in impaired reproductive function later in life. it is therefore important to evaluate long-term consequences of early life stage e ... | 2019 | 31069675 |
| disrupted plasma membrane protein homeostasis in a xenopus laevis model of retinitis pigmentosa. | rhodopsin mislocalization is frequently observed in retinitis pigmentosa (rp) patients. for example, class i mutant rhodopsin is deficient in the vxpx trafficking signal, mislocalizes to the plasma membrane (pm) of rod photoreceptor inner segments (iss), and causes autosomal dominant rp. mislocalized rhodopsin causes photoreceptor degeneration in a manner independent of light-activation. in this manuscript, we took advantage of xenopus laevis models of both sexes expressing wild-type human rhodo ... | 2019 | 31061086 |
| antinociceptive effects of new pyrazoles compounds mediated by the asic-1α channel, trpv-1 and μmor receptors. | pyrazoles are potent medicinal scaffolds and exhibit a wide spectrum of biological activities, such as analgesic, anti-inflammatory and antipyretic. in this paper we report on research we have performed with the aim of continuing the biological evaluation of the regio-isomeric pyrazole compounds, lqfm-020 (fluorine, para position), lqfm-021 (fluorine, meta position), and lqfm-039 (fluorine, ortho position) in models of pain induced by acidified saline, capsaicin, and formalin. we also investigat ... | 2019 | 31055237 |
| isolation of nanobodies against xenopus embryonic antigens using immune and non-immune phage display libraries. | the use of xenopus laevis as a model for vertebrate developmental biology is limited by a lack of antibodies specific for embryonic antigens. this study evaluated the use of immune and non-immune phage display libraries for the isolation of single domain antibodies, or nanobodies, with specificities for xenopus embryonic antigens. the immune nanobody library was derived from peripheral blood lymphocyte rna obtained from a llama immunized with xenopus gastrula homogenates. screening this library ... | 2019 | 31048885 |
| positively charged tags impede protein mobility in cells as quantified by 19f nmr. | proteins are often tagged for visualization or delivery in the "sea" of other macromolecules in cells but how tags affect protein mobility remains poorly understood. here, we employ in-cell 19f nmr to quantify the mobility of proteins with charged tags in escherichia coli cells and xenopus laevis oocytes. we find that the transient charge-charge interactions between the tag and cellular components affect protein mobility. more specifically, positively charged tags impede protein mobility. | 2019 | 31042382 |
| wolf-hirschhorn syndrome-associated genes are enriched in motile neural crest cells and affect craniofacial development in xenopus laevis. | wolf-hirschhorn syndrome (whs) is a human developmental disorder arising from a hemizygous perturbation, typically a microdeletion, on the short arm of chromosome four. in addition to pronounced intellectual disability, seizures, and delayed growth, whs presents with a characteristic facial dysmorphism and varying prevalence of microcephaly, micrognathia, cartilage malformation in the ear and nose, and facial asymmetries. these affected craniofacial tissues all derive from a shared embryonic pre ... | 2019 | 31031646 |
| methods for investigating trp channel gating. | a complete characterization of temperature -and voltage-activated trp channel gating requires a precise determination of the absolute probability of opening in a wide range of voltages, temperatures, and agonist concentrations. we have achieved this in the case of the trpm8 channel expressed in xenopus laevis oocytes. measurements covered an extensive range of probabilities and unprecedented applied voltages up to 500 mv. in this chapter, we describe animal care protocols of patch-clamp pipette ... | 2019 | 31028680 |
| the c-type atp-binding cassette transporter osabcc7 is involved in the root-to-shoot translocation of arsenic in rice. | rice is a major dietary source of inorganic arsenic (as), a nonthreshold carcinogen. reducing as accumulation in rice grain is of critical importance for food safety. in the present study, we investigated the role of a member of the rice c-type atp-binding cassette (abc) transporter (osabcc) family, osabcc7, in arsenite [as(iii)] accumulation in rice. quantitative real-time rt-pcr showed that osabcc7 was expressed intensively in the roots and the expression was strongly suppressed by as(iii) exp ... | 2019 | 31028396 |
| a ywhaz variant associated with cardiofaciocutaneous syndrome activates the raf-erk pathway. | cardiofaciocutaneous (cfc) syndrome is a genetic disorder characterized by distinctive facial features, congenital heart defects, and skin abnormalities. several germline gain-of-function mutations in the ras/raf/mek/erk pathway are associated with the disease, including kras, braf, mek1, and mek2. cfc syndrome thus belongs to a group of disorders known as rasopathies, which are all caused by pathogenic mutations in various genes encoding components of the ras pathway. we recently identified nov ... | 2019 | 31024343 |
| effects of nonylphenols on embryonic development and metamorphosis of xenopus laevis: fetax and amphibian metamorphosis toxicity test (oecd tg231). | nonylphenols (nps) are a group of endocrine-disrupting surfactants that mimic estrogen. to determine the developmental toxicity and thyroid-disrupting effect of nps, the effects of exposure to nonylphenol (np), 4-nonylphenol (4-np), and nonylphenol ethoxylate (np-12) were examined according to the frog embryo teratogenesis assay-xenopus (fetax) and organization for economic co-operation and development test guidelines 231 (tg231). in fetax, the lc50 values of np, 4-np, and np-12 were 59.14 mg/l, ... | 2019 | 31022611 |
| slpi inhibits atp-mediated maturation of il-1β in human monocytic leukocytes: a novel function of an old player. | interleukin-1β (il-1β) is a potent, pro-inflammatory cytokine of the innate immune system that plays an essential role in host defense against infection. however, elevated circulating levels of il-1β can cause life-threatening systemic inflammation. hence, mechanisms controlling il-1β maturation and release are of outstanding clinical interest. secretory leukocyte protease inhibitor (slpi), in addition to its well-described anti-protease function, controls the expression of several pro-inflammat ... | 2019 | 31019507 |
| special considerations for making explants and transplants with xenopus tropicalis. | although xenopus laevis is an important model organism for embryological experimentation, the smaller, more genetically tractable, and faster developing xenopus tropicalis provides advantages for using genetic approaches to understand developmental mechanisms. explant cultures and transplants of x. tropicalis embryonic tissues present unique opportunities to examine embryonic tissue determination in a simplified setting. here we demonstrate preparation of explants and transplants of preplacodal ... | 2019 | 31010887 |
| altering the levels of nuclear import factors in early xenopus laevis embryos affects later development. | more than just a container for dna, the nuclear envelope carries out a wide variety of critical and highly regulated cellular functions. one of these functions is nuclear import, and in this study we investigate how altering the levels of nuclear transport factors impacts developmental progression and organismal size. during early xenopus laevis embryogenesis, the timing of a key developmental event, the midblastula transition (mbt), is sensitive to nuclear import factor levels. how might alteri ... | 2019 | 31009515 |
| urokinase-type plasminogen activator (upa) is not essential for epithelial sodium channel (enac)-mediated sodium retention in experimental nephrotic syndrome. | in nephrotic syndrome, aberrantly filtered plasminogen (plg) is converted to active plasmin by tubular urokinase-type plasminogen activator (upa) and thought to lead to sodium retention by proteolytic activation of the epithelial sodium channel (enac). this concept predicts that upa is an important factor for sodium retention and that inhibition of upa might be protective in nephrotic syndrome. | 2019 | 31006168 |
| conservation and divergence of protein pathways in the vertebrate heart. | heart disease is the leading cause of death in the western world. attaining a mechanistic understanding of human heart development and homeostasis and the molecular basis of associated disease states relies on the use of animal models. here, we present the cardiac proteomes of 4 model vertebrates with dual circulatory systems: the pig (sus scrofa), the mouse (mus musculus), and 2 frogs (xenopus laevis and xenopus tropicalis). determination of which proteins and protein pathways are conserved and ... | 2019 | 31490923 |
| discovery of the arp2 protein as a determining molecule in tumor cell death. | cancer is a multifactorial disease that constitutes a serious public health problem worldwide. prostate cancer advanced stages are associated with the development of androgen-independent tumors and an apoptosis-resistant phenotype that progresses to metastasis. by studying androgen-independent lymphoid nodule carcinoma of the prostate (lncap) cells induced to apoptosis by serum elimination, we identified the activation of a non-selective cationic channel of 23ps conductance that promotes incomin ... | 2019 | 32091029 |
| descubrimiento de la proteína reguladora de apoptosis 2 como determinante en la muerte de células tumorales. | cancer is a multifactorial disease that constitutes a serious public health problem worldwide. prostate cancer advanced stages are associated with the development of androgen-independent tumors and an apoptosis-resistant phenotype that progresses to metastasis. by studying androgen-independent lymphoid nodule carcinoma of the prostate (lncap) cells induced to apoptosis by serum elimination, we identified the activation of a non-selective cationic channel of 23ps conductance that promotes incomin ... | 2019 | 31695224 |
| a flipr assay for discovery of gabaa receptor modulators of natural origin. | a fluorometric imaging plate reader (flipr) assay utilizing chinese hamster ovary (cho) cells stably transfected with gabaa receptors of α1β2γ2 subunit composition was evaluated and validated for rapid screening of plant extract libraries and efficient localization of active compounds in extracts. validation was performed with pure compounds and extracts known to contain allosteric gabaa receptor modulators. plants extracts that had been previously reported as active in an assay using xenopus la ... | 2019 | 31127604 |
| in vitro inhibition of human nucleoside transporters and uptake of azacitidine by an isocitrate dehydrogenase-2 inhibitor enasidenib and its metabolite agi-16903. | 1. the present study investigated inhibitory effects of enasidenib and its metabolite agi-16903 on (a) recombinant human nucleoside transporters (hnts) in hnt-producing xenopus laevis oocytes, and (b) azacitidine uptake in a normal b-lymphoblast peripheral blood cell line (pbc) and acute myeloid leukemia (aml) cell lines. 2. enasidenib inhibited hent1, hent2, hent3, and hent4 in oocytes with ic50 values of 7, 63, 27, and 76 μm, respectively, but exhibited little inhibition of hcnt1-3. agi-16903 ... | 2019 | 30394160 |
| paracetamol-induced liver injury modelled in xenopus laevis embryos. | failure to predict drug-induced liver injury (dili) remains a major contributing factor to lead compound drop-out during drug development. xenopus embryos are amenable for early stage medium throughput small molecule screens and so have the potential to be used in pre-clinical screens. to begin to assess the usefulness and limitations of xenopus embryos for safety assessment in the early phases of drug development, paracetamol was used as a model hepatotoxin. paracetamol overdose is associated w ... | 2019 | 30282005 |
| [exploring the mysteries of megakaryocytopoiesis and thrombopoiesis through comparative hematology]. | in modern hematology, research on hematopoiesis and blood cells in vertebrates, such as birds, reptiles, amphibians, and fish, is lagging. this is because there are many experimental constraints when selecting subjects other than humans and mice as research subjects. currently, the availability of flow cytometry to count classified nucleated blood cells and utilization of whole genome information have led to novel findings. for example, in case of amphibian hematopoiesis studies, megakaryocytes ... | 2019 | 31597828 |
| distinct host-mycobacterial pathogen interactions between resistant adult and tolerant tadpole life stages of xenopus laevis. | mycobacterium marinum is a promiscuous pathogen infecting many vertebrates, including humans, whose persistent infections are problematic for aquaculture and public health. among unsettled aspects of host-pathogen interactions, the respective roles of conventional and innate-like t (it) cells in host defenses against m. marinum remain unclear. in this study, we developed an infection model system in the amphibian xenopus laevis to study host responses to m. marinum at two distinct life stages, t ... | 2019 | 31591148 |
| different pharmacological properties of glut9a and glut9b: potential implications in preeclampsia. | glucose transporter 9 (glut9/slc2a9) is the major regulator of uric acid homeostasis in humans. hyperuricemia due to impaired regulation by glut9 in pregnancy is closely associated with preeclampsia. while glut9 is expressed in two alternative splice variants, glut9a and glut9b, with different subcellular localizations, no functional differences of the two splice variants are known to date. the aim of this study was to investigate the function of both glut9 isoforms. | 2019 | 31502429 |
| heterologous hyaluronic acid production in kluyveromyces lactis. | hyaluronic acid (ha) is a biopolymer composed by the monomers glucuronic acid (glcua) and n-acetyl glucosamine (glcnac). it has a broad range of applications in the field of medicine, being marketed between usd 1000-5000/kg. its primary sources include extraction of animal tissue and fermentation using pathogenic bacteria. however, in both cases, extensive purification protocols are required to prevent toxin contamination. in this study, aiming at creating a safe ha producing microorganism, the ... | 2019 | 31466214 |
| advancing genetic and genomic technologies deepen the pool for discovery in xenopus tropicalis. | xenopus laevis and xenopus tropicalis have long been used to drive discovery in developmental, cell, and molecular biology. these dual frog species boast experimental strengths for embryology including large egg sizes that develop externally, well-defined fate maps, and cell-intrinsic sources of nutrients that allow explanted tissues to grow in culture. development of the xenopus cell extract system has been used to study cell cycle and dna replication. xenopus tadpole tail and limb regeneration ... | 2019 | 31254427 |
| adaptive correction of craniofacial defects in pre-metamorphic xenopus laevis tadpoles involves thyroid hormone-independent tissue remodeling. | although it is well established that some organisms can regenerate lost structures, the ability to remodel existing malformed structures has been less well studied. therefore, in this study we examined the ability of pre-metamorphic xenopus laevis tadpoles to self-correct malformed craniofacial tissues. we found that tadpoles can adaptively improve and normalize abnormal craniofacial morphology caused by numerous developmental perturbations. we then investigated the tissue-level and molecular me ... | 2019 | 31253636 |
| the amphibian (xenopus laevis) colony-stimulating factor-1 and interleukin-34-derived macrophages possess disparate pathogen recognition capacities. | pathogens such as the frog virus 3 (fv3) ranavirus are contributing to the worldwide amphibian declines. while amphibian macrophages (mϕs) are central to the immune defenses against these viruses, the pathogen recognition capacities of disparate amphibian mϕ subsets remain unexplored. in turn, mϕ differentiation and functionality are interdependent on the colony-stimulating factor-1 receptor (csf-1r), which is ligated by colony-stimulating factor-1 (csf-1) and the unrelated interleukin-34 (il-34 ... | 2019 | 31029710 |
| the voltage sensing phosphatase (vsp) localizes to the apical membrane of kidney tubule epithelial cells. | voltage-sensing phosphatases (vsps) are transmembrane proteins that couple changes in membrane potential to hydrolysis of inositol signaling lipids. vsps catalyze the dephosphorylation of phosphatidylinositol phosphates (pips) that regulate diverse aspects of cell membrane physiology including cell division, growth and migration. vsps are highly conserved among chordates, and their rna transcripts have been detected in the adult and embryonic stages of frogs, fish, chickens, mice and humans. how ... | 2019 | 30964862 |
| developmental exposure to chemicals associated with unconventional oil and gas extraction alters immune homeostasis and viral immunity of the amphibian xenopus. | although aquatic vertebrates and humans are increasingly exposed to water pollutants associated with unconventional oil and gas extraction (uog), the long-term effects of these pollutants on immunity remains unclear. we have established the amphibian xenopus laevis and the ranavirus frog virus 3 (fv3) as a reliable and sensitive model for evaluating the effects of waterborne pollutants. x. laevis tadpoles were exposed to a mixture of equimass amount of uog chemicals with endocrine disrupting act ... | 2019 | 30939317 |
| developmental regulation of wnt signaling by nagk and the udp-glcnac salvage pathway. | in a screen for human kinases that regulate xenopus laevis embryogenesis, we identified nagk and other components of the udp-glcnac glycosylation salvage pathway as regulators of anteroposterior patterning and wnt signaling. we find that the salvage pathway does not affect other major embryonic signaling pathways (fgf, tgfβ, notch, or shh), thereby demonstrating specificity for wnt signaling. we show that the role of the salvage pathway in wnt signaling is evolutionarily conserved in zebrafish a ... | 2019 | 30904594 |
| stage-dependent cardiac regeneration in xenopus is regulated by thyroid hormone availability. | despite therapeutic advances, heart failure is the major cause of morbidity and mortality worldwide, but why cardiac regenerative capacity is lost in adult humans remains an enigma. cardiac regenerative capacity widely varies across vertebrates. zebrafish and newt hearts regenerate throughout life. in mice, this ability is lost in the first postnatal week, a period physiologically similar to thyroid hormone (th)-regulated metamorphosis in anuran amphibians. we thus assessed heart regeneration in ... | 2019 | 30755533 |
| ketone body modulation of ligand-gated ion channels. | ketogenesis is a metabolic process wherein ketone bodies are produced from the breakdown of fatty acids. in humans, fatty acid catabolism results in the production of acetyl-coa which can then be used to synthesize three ketone bodies: acetoacetate, acetone, and β-hydroxybutyrate. ketogenesis occurs at a higher rate in situations of low blood glucose, such as during fasting, heavy alcohol consumption, and in situations of low insulin, as well as in individuals who follow a 'ketogenic diet' consi ... | 2019 | 30562540 |
| heterologous expression of aedes aegypti cation chloride cotransporter 2 (aeccc2) in xenopus laevis oocytes induces an enigmatic na⁺/li⁺ conductance. | the yellow fever mosquito aedes aegypti possesses three genes encoding putative na⁺-coupled cation chloride cotransporters (cccs): aenkcc1, aeccc2, and aeccc3. to date, none of the aecccs have been functionally characterized. here we expressed aeccc2 heterologously in xenopus oocytes and measured the uptake of li⁺ (a tracer for na⁺) and rb⁺ (a tracer for k⁺). compared to control (h₂o-injected) oocytes, the aeccc2-expressing oocytes exhibited significantly greater uptake of li⁺, but not rb⁺. howe ... | 2019 | 30875796 |
| the effects of insecticides on two splice variants of the glutamate-gated chloride channel receptor of the major malaria vector, anopheles gambiae. | between half to 1 million people die annually from malaria. anopheles gambiae mosquitoes are major malaria vectors. unfortunately, resistance has emerged to the agents currently used to control a. gambiae, creating a demand for novel control measures. the pentameric glutamate-gated chloride channel (glucl) expressed in the muscle and nerve cells of these organisms are a potentially important biological target for malaria control. the pharmacological properties of anophiline glucl receptors are, ... | 2019 | 31479507 |
| periodic albinism of a widely used albino mutant of xenopus laevis caused by deletion of two exons in the hermansky-pudlak syndrome type 4 gene. | the periodic albino mutant of xenopus laevis is a recessive mutant, in which reduced amounts of melanin appear in the retinal pigment epithelium (rpe) and in melanophores at the late embryonic stage, after which both rpe and melanophores gradually depigment. three types of pigment cells (melanophores, iridophores, and xanthophores) have been reported to be affected in this albino. however, the causative gene of the periodic albinism remains unknown. hermansky-pudlak syndrome (hps) is an autosoma ... | 2020 | 33147376 |
| disease-associated hcn4 v759i variant is not sufficient to impair cardiac pacemaking. | the hyperpolarization-activated cation current if is a key determinant for cardiac pacemaker activity. it is conducted by subunits of the hyperpolarization-activated cyclic nucleotide-gated (hcn) channel family, of which hcn4 is predominant in mammalian heart. both loss-of-function and gain-of-function mutations of the hcn4 gene are associated with sinus node dysfunction in humans; however, their functional impact is not fully understood yet. here, we sought to characterize a hcn4 v759i variant ... | 2020 | 33095298 |
| using an aquatic model, xenopus laevis, to uncover the role of chromodomain 1 in craniofacial disorders. | the chromodomain family member chromodomain 1 (chd1) has been shown to have numerous critical molecular functions including transcriptional regulation, splicing, and dna repair. complete loss of function of this gene is not compatible with life. on the other hand, missense and copy number variants of chd1 can result in intellectual disabilities and craniofacial malformations in human patients including cleft palate and pilarowski-bjornsson syndrome. we have used the aquatic developmental model o ... | 2020 | 32918369 |
| acute consequences of a unilateral viiith nerve transection on vestibulo-ocular and optokinetic reflexes in xenopus laevis tadpoles. | loss of peripheral vestibular function provokes severe impairments of gaze and posture stabilization in humans and animals. however, relatively little is known about the extent of the instantaneous deficits. this is mostly due to the fact that in humans a spontaneous loss often goes unnoticed initially and targeted lesions in animals are performed under deep anesthesia, which prevents immediate evaluation of behavioral deficits. here, we use isolated preparations of xenopus laevis tadpoles with ... | 2020 | 32915311 |
| l-glutamic acid monosodium salt reduces the harmful effect of lithium on the development of xenopus laevis embryos. | many xenobiotics in the environment affect the human body in various ways. among those xenobiotics, lithium chloride (li, licl) and monosodium glutamate (l-glutamic acid monosodium salt, msg) compounds affect the crucial processes of stem cell differentiation, cell proliferation, developmental gene expression, and overall development in animals. in this study, we aimed to examine the developmental effects of exposure to flavor enhancer msg and lici medicament on xenopus embryos using the frog em ... | 2020 | 32705564 |
| uncoupling sodium channel dimers restores the phenotype of a pain-linked nav 1.7 channel mutation. | the voltage-gated sodium channel nav 1.7 is essential for adequate perception of painful stimuli. mutations in the encoding gene, scn9a, cause various pain syndromes in humans. the hnav 1.7/a1632e channel mutant causes symptoms of erythromelalgia and paroxysmal extreme pain disorder (pepd), and its main gating change is a strongly enhanced persistent current. on the basis of recently published 3d structures of voltage-gated sodium channels, we investigated how the inactivation particle binds to ... | 2020 | 32663327 |
| trpm6 and trpm7: novel players in cell intercalation during vertebrate embryonic development. | a common theme in organogenesis is how the final structure of organs emerge from epithelial tube structures, with the formation of the neural tube being one of the best examples. two types of cell movements co-occur during neural tube closure involving the migration of cells toward the midline of the embryo (mediolateral intercalation or convergent extension) as well as the deep movement of cells from inside the embryo to the outside of the lateral side of the neural plate (radial intercalation) ... | 2020 | 32315468 |
| effects of bisphenol a and its alternative bisphenol f on notch signaling and intestinal development: a novel signaling by which bisphenols disrupt vertebrate development. | we previously found bisphenol a (bpa) alternative, bisphenol f (bpf) upregulated notch-related gene expression in intestines of the african clawed frog xenopus laevis, suggesting an agonistic action on notch signaling, a crucial signaling in multiple biological processes during development. here, we aimed to confirm the actions of bpa and bpf on notch signaling and to reveal their effects on intestinal development. using x. laevis, an excellent model for developmental biology, we found that 10-1 ... | 2020 | 32311622 |
| modeling bainbridge-ropers syndrome in xenopus laevis embryos. | the additional sex combs-like (asxl1-3) genes are linked to human neurodevelopmental disorders. the de novo truncating variants in asxl1-3 proteins serve as the genetic basis for severe neurodevelopmental diseases such as bohring-opitz, shashi-pena, and bainbridge-ropers syndromes, respectively. the phenotypes of these syndromes are similar but not identical, and include dramatic craniofacial defects, microcephaly, developmental delay, and severe intellectual disability, with a loss of speech an ... | 2020 | 32132929 |
| hplc reveals novel features of nucleoside and nucleobase homeostasis, nucleoside metabolism and nucleoside transport. | humans possess three members of the cation-coupled concentrative nucleoside transporter cnt (slc 28) family, hcnt1-3: hcnt1 is selective for pyrimidine nucleosides but also transports adenosine, hcnt2 transports purine nucleosides and uridine, and hcnt3 transports both pyrimidine and purine nucleosides. hcnt1/2 transport nucleosides using the transmembrane na+ electrochemical gradient, while hcnt3 is both na+- and h+-coupled. by producing recombinant hcnt3 in xenopus laevis oocytes, we have used ... | 2020 | 32126230 |
| evaluation of the effects of low concentrations of bisphenol af on gonadal development using the xenopus laevis model: a finding of testicular differentiation inhibition coupled with feminization. | developmental exposures to estrogenic chemicals possibly cause structural and functional abnormalities of reproductive organs in vertebrates. bisphenol af (bpaf), a bisphenol a (bpa) analogue, has been shown to have higher estrogenic activity than bpa, but little is known about the effects of bpaf on gonadal development, particularly gonadal differentiation. we aimed to determine whether low concentrations of bpaf could disrupt gonadal differentiation and subsequent development using xenopus lae ... | 2020 | 31991354 |
| cfap43 modulates ciliary beating in mouse and xenopus. | malfunctions of motile cilia cause a variety of developmental defects and diseases in humans and animal model organisms. defects include impaired mucociliary clearance of the airways, sperm immotility, hydrocephalus and organ laterality. here, we characterize the evolutionary conserved cfap43 gene by loss-of-function experiments in the mouse and the frog xenopus laevis. cfap43 is expressed in tissues carrying motile cilia and acts as a target gene of the transcription factor foxj1, which is esse ... | 2020 | 31884020 |
| insights regarding skin regeneration in non-amniote vertebrates: skin regeneration without scar formation and potential step-up to a higher level of regeneration. | skin wounds are among the most common injuries in animals and humans. vertebrate skin is composed of an epidermis and dermis. after a deep skin injury in mammals, the wound heals, but the dermis cannot regenerate. instead, collagenous scar tissue forms to fill the gap in the dermis, but the scar does not function like the dermis and often causes disfiguration. in contrast, in non-amniote vertebrates, including fish and amphibians, the dermis and skin derivatives are regenerated after a deep skin ... | 2020 | 31831357 |
| impact of copper in xenopus laevis liver: histological damages and atp7b downregulation. | copper is an essential micronutrient but its excess in the dietary can be toxic. both copper deficiency and abundance can occur in natural conditions and can lead to pathological dysfunctions. many of the toxic effects of copper, such as increased lipid peroxidation in cell membranes and dna damage, are due to its role in the generation of oxygen free radicals. copper is released into the environment by both natural sources and human activities and it can damage organisms and ecosystems. in the ... | 2020 | 31757510 |
| evaluation of a multiplexed, multispecies nuclear receptor assay for chemical hazard assessment. | sensitivity to potential endocrine disrupting chemicals in the environment varies across species and is influenced by sequence conservation of their nuclear receptor targets. here, we evaluated a multiplexed, in vitro assay testing receptors relevant to endocrine and metabolic disruption from five species. the trans-factorial™ system of human nuclear receptors was modified to include additional species: mouse (mus musculus), frog (xenopus laevis), zebrafish (danio rerio), chicken (gallus gallus) ... | 2020 | 33049310 |
| organelle size scaling over embryonic development. | cell division without growth results in progressive cell size reductions during early embryonic development. how do the sizes of intracellular structures and organelles scale with cell size and what are the functional implications of such scaling relationships? model organisms, in particular caenorhabditis elegans worms, drosophila melanogaster flies, xenopus laevis frogs, and mus musculus mice, have provided insights into developmental size scaling of the nucleus, mitotic spindle, and chromosom ... | 2020 | 32003549 |
| polyunsaturated fatty acid-derived iks channel activators shorten the qt interval ex-vivo and in-vivo. | we aimed to assess the ability of natural and modified polyunsaturated fatty acids (pufas) to shorten qt interval in ex-vivo and in-vivo guinea pig hearts. | 2020 | 32223014 |
| modulation by neonicotinoids of honeybee α1/chicken β2 hybrid nicotinic acetylcholine receptors expressed in xenopus laevis oocytes. | neonicotinoids targeting insect nicotinic acetylcholine (ach) receptors (insect nachrs) are used for crop protection, but there is a concern about adverse effects on pollinators such as honeybees (apis mellifera). thus, we investigated the agonist actions of neonicotinoids (imidacloprid, thiacloprid and clothianidin) on a. mellifera α1 (amα1)/chicken β2 hybrid nachrs in xenopus laevis oocytes according to the subunit stoichiometry of (amα1)3(β2)2 and (amα1)2(β2)3 using voltage-clamp electrophysi ... | 2020 | 32448414 |
| the mechanism of loop c-neonicotinoid interactions at insect nicotinic acetylcholine receptor α1 subunit predicts resistance emergence in pests. | neonicotinoids selectively modulate insect nicotinic acetylcholine receptors (insect nachrs). studies have shown that serine with ability to form a hydrogen bond in loop c of some insect nachr α subunits and glutamate with a negative charge at the corresponding position in vertebrate nachrs may contribute to enhancing and reducing the neonicotinoid actions, respectively. however, there is no clear evidence what loop c properties underpin the target site actions of neonicotinoids. thus, we have i ... | 2020 | 32371996 |
| effects of copper on the neuromasts of xenopus laevis. | fish and aquatic amphibians possess neuromasts on the surface of their body that constitute the lateral line, a sensory system used to detect water displacement. copper is known to inactivate the neuromast organs of this system. copper-induced neuromast loss in african clawed frogs, xenopus laevis, was examined by exposing nieuwkoop-faber stage 54-55 larvae to copper concentrations of 0, 100, 200, 300, and 400 µg/l for 96 h, followed by an examination of neuromast counts, staining intensity, and ... | 2020 | 33180147 |
| ecotoxicological assessment of commercial boron nitride nanotubes toward xenopus laevis tadpoles and host-associated gut microbiota. | despite the growing interest for boron nitride nanotubes (bnnt) due to their unique properties, data on the evaluation of the environmental risk potential of this emerging engineered nanomaterial are currently lacking. therefore, the ecotoxicity of a commercial form of bnnt (containing tubes, hexagonal-boron nitride, and boron) was assessed in vivo toward larvae of the amphibian xenopus laevis. following the exposure, multiple endpoints were measured in the tadpoles as well as in bacterial commu ... | 2020 | 33171057 |
| mechanisms activating latent functions of pip aquaporin water channels via the interaction between pip1 and pip2 proteins. | plant plasma-membrane type pip aquaporins are classified into two groups, pip1s and pip2s. in this study, we focused on hvpip1; 2, a pip1 in barley (hordeum vulgare), to dissect the molecular mechanisms that evoke hvpip1-mediated water transport. no hvpip1; 2 protein was localized to the plasma membrane when expressed alone in xenopus laevis oocytes. in contrast, a chimeric hvpip1; 2 protein (hvpip1; 2_24nc), in which the n- and c-terminal regions were replaced with the corresponding regions fro ... | 2020 | 33169164 |
| epigenetic regulation of replication origin assembly: a role for histone h1 and chromatin remodeling factors. | during early embryonic development in several metazoans, accurate dna replication is ensured by high number of replication origins. this guarantees rapid genome duplication coordinated with fast cell divisions. in xenopus laevis embryos this program switches to one with a lower number of origins at a developmental stage known as mid-blastula transition (mbt) when cell cycle length increases and gene transcription starts. consistent with this regulation, somatic nuclei replicate poorly when trans ... | 2020 | 33165968 |
| synthesis of glun2a-selective nmda receptor antagonists with an electron-rich aromatic b-ring. | glutamatergic n-methyl-d-aspartate (nmda) receptors are heterotetrameric ion channels that can be comprised of different subunits. glun2a subunit-containing nmda receptors are associated with diseases like anxiety, depression, and schizophrenia. however, the exact contribution of these nmda receptor subtypes is still unclear. to understand better the role of the glun2a-containing receptors, novel ligands were designed. in co-crystallization with the isolated binding site, tcn-201 (1) and analogs ... | 2020 | 33162207 |
| trim-away mediated knock down uncovers a new function for lbh during gastrulation of xenopus laevis. | we previously identified the protein lbh as necessary for cranial neural crest (cnc) cell migration in xenopus through the use of morpholinos. however, lbh is a maternally deposited protein and morpholinos achieve knockdowns through prevention of translation. in order to investigate the role of lbh in earlier embryonic events, we employed the new technique "trim-away" to degrade this maternally deposited protein. trim-away utilizes the e3 ubiquitin ligase trim21 to degrade proteins targeted with ... | 2020 | 33159936 |
| kunitz-type peptides from the sea anemone heteractis crispa demonstrate potassium channel blocking and anti-inflammatory activities. | the kunitz/bpti peptide family includes unique representatives demonstrating various biological activities. electrophysiological screening of peptides hcrg1 and hcrg2 from the sea anemone heteractis crispa on six kv1.x channel isoforms and insect shaker ir channel expressed in xenopus laevis oocytes revealed their potassium channels blocking activity. hcrg1 and hcrg2 appear to be the first kunitz-type peptides from sea anemones blocking kv1.3 with ic50 of 40.7 and 29.7 nm, respectively. in addit ... | 2020 | 33158163 |
| development of antimicrobial peptides from amphibians. | since the discovery of magainins from the skin secretions of the african toad xenopus laevis by michael zasloff in 1987, an increasing number of antimicrobial peptides (amps) has been identified in different anuran species and studied in detail [...]. | 2020 | 33158031 |
| antimicrobial peptide induced-stress renders staphylococcus aureus susceptible to toxic nucleoside analogs. | cationic antimicrobial peptides (amps) are active immune effectors of multicellular organisms and are also considered as new antimicrobial drug candidates. one of the problems encountered when developing amps as drugs is the difficulty of reaching sufficient killing concentrations under physiological conditions. here, using pexiganan, a cationic peptide derived from a host defense peptide of the african clawed frog and the first amp developed into an antibacterial drug, we studied whether sub-le ... | 2020 | 33133056 |
| nicotinic acetylcholine receptors in the synganglion of the tick ixodes ricinus: functional characterization using membrane microtransplantation. | nicotinic acetylcholine receptors are an important class of excitatory receptors in the central nervous system of arthropods. in the ticks ixodes ricinus, the functional and pharmacological properties of nicotinic receptors located in their neurons are still unknown. the objective of this study was to characterize the pharmacological properties of tick nicotinic receptors using membrane microtransplantation in xenopus laevis oocytes and two-electrodes voltage clamp method. the membranes microtra ... | 2020 | 33120248 |
| observation of nucleic acids inside living human cells by in-cell nmr spectroscopy. | the intracellular environment is highly crowded with biomacromolecules such as proteins and nucleic acids. under such conditions, the structural and biophysical features of nucleic acids have been thought to be different from those in vitro. to obtain high-resolution structural information on nucleic acids in living cells, the in-cell nmr method is a unique tool. following the first in-cell nmr measurement of nucleic acids in 2009, several interesting insights were obtained using xenopus laevis ... | 2020 | 33110737 |
| high affinity na+ transport by wheat hkt1;5 is blocked by k. | the wheat sodium transporters tmhkt1;5-a and tahkt1;5-d are encoded by genes underlying the major shoot na+ exclusion loci nax2 and kna1 from triticum monococcum (tm) and triticum aestivum (ta), respectively. in contrast to hkt2 transporters that have been shown to exhibit high affinity k+-dependent na+ transport, hkt1 proteins have, with one exception, only been shown to catalyze low affinity na+ transport and no k+ transport. here, using heterologous expression in xenopus laevis oocytes we unc ... | 2020 | 33103046 |
| x-box-binding protein 1 is required for pancreatic development in xenopus laevis. | x-box-binding protein 1 (xbp1) is a protein containing the basic leucine zipper structure. it belongs to the camp-response element binding protein (creb)/activating transcription factor transcription factor family. as the main transcription factor, spliced xbp1 (xbp1s) participates in many physiological and pathological processes and plays an important role in embryonic development. previous studies showed that xbp1-knockout mice died because of pancreatic exocrine function deficiency, indicatin ... | 2020 | 33098302 |
| sclerostin inhibits wnt signaling through tandem interaction with two lrp6 ectodomains. | low-density lipoprotein receptor-related protein 6 (lrp6) is a coreceptor of the β-catenin-dependent wnt signaling pathway. the lrp6 ectodomain binds wnt proteins, as well as wnt inhibitors such as sclerostin (sost), which negatively regulates wnt signaling in osteocytes. although lrp6 ectodomain 1 (e1) is known to interact with sost, several unresolved questions remain, such as the reason why sost binds to lrp6 e1e2 with higher affinity than to the e1 domain alone. here, we present the crystal ... | 2020 | 33097721 |
| rad21 is involved in corneal stroma development by regulating neural crest migration. | previously, we identified rad21r450c from a peripheral sclerocornea pedigree. injection of this rad21 variant mrna into xenopus laevis embryos disrupted the organization of corneal stroma fibrils. to understand the mechanisms of rad21-mediated corneal stroma defects, gene expression and chromosome conformation analysis were performed using cells from family members affected by peripheral sclerocornea. both gene expression and chromosome conformation of cell adhesion genes were affected in cells ... | 2020 | 33096935 |
| phosphoproteomic analysis of xenopus laevis reveals expression and phosphorylation of hypoxia-inducible pfkfb3 during dehydration. | xenopus laevis tolerate dehydration when their environments evaporate during summer months. protein phosphorylation has previously shown to regulate important adaptations in x. laevis, including the transition to anaerobic metabolism. we therefore performed phosphoproteomic analysis of x. laevis to further elucidate the cellular and metabolic responses to dehydration. phosphoproteins were enriched in cellular functions and pathways related to glycolysis/gluconeogenesis, the tca cycle, and protei ... | 2020 | 33083755 |
| derivation of proliferative islet1-positive cells during metamorphosis and wound response in xenopus. | in mammalian hearts, cardiomyocytes retain a transient capacity to proliferate and regenerate following injury before birth, whereas they lose proliferative capacity immediately after birth. it has also been known that cardiac progenitor cells including islet1-positive cells do not contribute to the cardiac repair and regeneration in mammals. in contrast, hearts of zebrafish, amphibians and reptiles maintain a regenerative ability throughout life. here, we analyzed proliferative capacity of card ... | 2020 | 33070205 |
| non-junctional role of cadherin3 in cell migration and contact inhibition of locomotion via domain-dependent, opposing regulation of rac1. | classical cadherins are well-known adhesion molecules responsible for physically connecting neighboring cells and signaling this cell-cell contact. recent studies have suggested novel signaling roles for "non-junctional" cadherins (njcads); however, the function of cadherin signaling independent of cell-cell contacts remains unknown. in this study, mesendodermal cells and tissues from gastrula stage xenopus laevis embryos demonstrate that deletion of extracellular domains of cadherin3 (cdh3; for ... | 2020 | 33060598 |
| scorpion toxin meunatxα-1 sensitizes primary nociceptors by selective modulation of voltage-gated sodium channels. | venoms are a rich source of highly specific toxins, which allow the identification of novel therapeutic targets. we have now applied high content screening (hcs) microscopy to identify toxins that modulate pain sensitization signaling in primary sensory neurons of rat and elucidated the underlying mechanism. a set of venoms and fractions thereof were analyzed for their ability to activate type ii protein kinase a (pka-ii) and extracellular signal-regulated kinases (erk1/2). we identified meunatx ... | 2020 | 33051988 |
| glutamate, d-(-)-2-amino-5-phosphonopentanoic acid, and n-methyl-d-aspartate do not directly modulate glycine receptors. | replication studies play an essential role in corroborating research findings and ensuring that subsequent experimental works are interpreted correctly. a previously published paper indicated that the neurotransmitter glutamate, along with the compounds n-methyl-d-aspartate (nmda) and d-(-)-2-amino-5-phosphonopentanoic acid (ap5), acts as positive allosteric modulators of inhibitory glycine receptors. the paper further suggested that this form of modulation would play a role in setting the spina ... | 2020 | 33051383 |
| whole-brain calcium imaging in larval xenopus. | sensory systems detect environmental stimuli and transform them into electrical activity patterns interpretable by the central nervous system. en route to higher brain centers, the initial sensory input is successively transformed by interposed secondary processing centers. mapping the neuronal activity patterns at all of those stages is essential to understand sensory information processing. larval xenopus laevis is very well-suited for whole-brain imaging of neuronal activity. this is mainly d ... | 2020 | 33037078 |
| elucidating the framework for specification and determination of the embryonic retina. | how cell determination is regulated remains a major unsolved problem in developmental biology. the early embryonic rudiments of many tissues and organs are difficult or impossible to identify, isolate and study at the time when determination occurs. we have examined the commitment process leading to retina formation in xenopus laevis, where presumptive eye tissue can be identified and studied to assay its biological properties during the events leading up to determination. we find that for the r ... | 2020 | 33031807 |
| microtubule-dependent pushing forces contribute to long-distance aster movement and centration in xenopus laevis egg extracts. | during interphase of the eukaryotic cell cycle, the microtubule (mt) cytoskeleton serves as both a supportive scaffold for organelles and an arborized system of tracks for intracellular transport. at the onset of mitosis, the position of the astral mt network, specifically its center, determines the eventual location of the spindle apparatus and ultimately the cytokinetic furrow. positioning of the mt aster often results in its movement to the center of a cell, even in large blastomeres hundreds ... | 2020 | 33026931 |
| cross-talk between p2x and nmda receptors. | purinergic p2x receptors (p2x) are atp-gated ion channels widely expressed in the cns. while the direct contribution of p2x to synaptic transmission is uncertain, p2x reportedly affect n-methyl-d-aspartate receptor (nmdar) activity, which has given rise to competing theories on the role of p2x in the modulation of synapses. however, p2x have also been shown to participate in receptor cross-talk: an interaction where one receptor (e.g., p2x2) directly influences the activity of another (e.g., nic ... | 2020 | 33003406 |
| dna content contributes to nuclear size control in xenopus laevis. | cells adapt to drastic changes in genome quantity during evolution and cell division by adjusting the nuclear size to exert genomic functions. however, the mechanism by which dna content within the nucleus contributes to controlling the nuclear size remains unclear. here, we experimentally evaluated the effects of dna content by utilizing cell-free xenopus egg extracts and imaging of in vivo embryos. upon manipulation of dna content while maintaining cytoplasmic effects constant, both plateau si ... | 2020 | 32997613 |
| torc1 selectively regulates synaptic maturation and input convergence in the developing visual system. | newly synthesized proteins support the development of functional neural circuits and previous work has suggested that dysregulated translation mediates certain forms of autism spectrum disorder (asd). here, we investigated the role of target of rapamycin complex 1 (torc1) in synaptic and dendritic development in vivo in the retinotectal system of xenopus laevis tadpoles. we found that torc1 signaling regulates dendritic growth and branching and that acute over-activation of torc1 by rheb overexp ... | 2020 | 32996262 |
| a survey of barley pip aquaporin ionic conductance reveals ca2+-sensitive hvpip2;8 na+ and k+ conductance. | some plasma membrane intrinsic protein (pip) aquaporins can facilitate ion transport. here we report that one of the 12 barley pips (pip1 and pip2) tested, hvpip2;8, facilitated cation transport when expressed in xenopus laevis oocytes. hvpip2;8-associated ion currents were detected with na+ and k+, but not cs+, rb+, or li+, and was inhibited by ba2+, ca2+, and cd2+ and to a lesser extent mg2+, which also interacted with ca2+. currents were reduced in the presence of k+, cs+, rb+, or li+ relativ ... | 2020 | 32992595 |
| inferring a complete genotype-phenotype map from a small number of measured phenotypes. | understanding evolution requires detailed knowledge of genotype-phenotype maps; however, it can be a herculean task to measure every phenotype in a combinatorial map. we have developed a computational strategy to predict the missing phenotypes from an incomplete, combinatorial genotype-phenotype map. as a test case, we used an incomplete genotype-phenotype dataset previously generated for the malaria parasite's 'chloroquine resistance transporter' (pfcrt). wild-type pfcrt (pfcrt3d7) lacks signif ... | 2020 | 32991585 |
| the mechanism of nmda receptor hyperexcitation in high pressure helium and hyperbaric oxygen. | professional divers exposed to pressures greater than 1.1 mpa may suffer from the high pressure neurological syndrome (hpns). divers who use closed-circuit breathing apparatus face the risk of cns hyperbaric oxygen toxicity (hbotox). both syndromes are characterized by reversible cns hyperexcitability, accompanied by cognitive and motor deficits. previous studies have demonstrated that the hyperexcitability of hpns is induced mainly by nmda receptors (nmdars). in our recent studies, we demonstra ... | 2020 | 32982789 |
| in-cell nmr spectroscopy of functional riboswitch aptamers in eukaryotic cells. | we report here the in-cell nmr-spectroscopic observation of the binding of the cognate ligand 2'-deoxyguanosine to the aptamer domain of the bacterial 2'-deoxyguanosine-sensing riboswitch in eukaryotic cells, namely xenopus laevis oocytes and in human hela cells. the riboswitch is sufficiently stable in both cell types to allow for detection of binding of the ligand to the riboswitch. most importantly, we show that the binding mode established by in vitro characterization of this prokaryotic rib ... | 2020 | 32975353 |
| design, synthesis, and in vitro evaluation of p2x7 antagonists. | the p2x7 receptor is a promising target for the treatment of various diseases due to its significant role in inflammation and immune cell signaling. this work describes the design, synthesis, and in vitro evaluation of a series of novel derivatives bearing diverse scaffolds as potent p2x7 antagonists. our approach was based on structural modifications of reported (adamantan-1-yl)methylbenzamides able to inhibit the receptor activation. the adamantane moieties and the amide bond were replaced, an ... | 2020 | 32964578 |
| endoparasites infecting exotic captive amphibian pet and zoo animals (anura, caudata) in germany. | alongside exotic reptiles, amphibians, such as toads, frogs, salamanders, and newts, are nowadays considered popular pets worldwide. as reported for other exotic pet animals, amphibians are known to harbor numerous gastrointestinal parasites. nonetheless, very little data are available on captive amphibian parasitic diseases. in this study, we applied direct saline fecal smears (dsfs) to examine in total 161 stool samples from 41 different amphibian species belonging to the orders anura and caud ... | 2020 | 32960371 |
| amiodarone bioconcentration and suppression of metamorphosis in xenopus. | trace concentrations of a number of pharmaceutically active compounds have been detected in the aquatic environment in many countries, where they are thought to have the potential to exert adverse effects on non-target organisms. amiodarone (amd) is one such high-risk compound commonly used in general hospitals. amd is known to alter normal thyroid hormone (th) function, although little information is available regarding the specific mechanism by which this disruption occurs. anuran tadpole meta ... | 2020 | 32956954 |
| aquaporin expression in the alimentary canal of the honey bee apis mellifera l. (hymenoptera: apidae) and functional characterization of am_eglp 1. | aquaporins (aqp) are a family of plasma membrane proteins responsible for water transport through cell membranes. they are differentially expressed in different parts of the alimentary canal of insects where they regulate water transport. these proteins have been studied in detail in some insects, but few data are available for aquaporins of the honey bee, apis mellifera. we used quantitative pcr to study the expression of six putative aquaporin genes in forager honey bees. we found differential ... | 2020 | 32956406 |
| do muscle contractile properties drive differences in locomotor performance in invasive populations of xenopus laevis in france? | jumping and swimming are key locomotor traits in frogs intimately linked to survival and dispersal. french populations of the frog xenopus laevis from the invasion front are known to possess greater terrestrial locomotor endurance. here, we tested whether individuals from the invasion front show differences in their muscle physiology that may underlie the observed whole-organism performance differences. we measured muscle contractile properties of the isolated gastrocnemius muscle in vitro, incl ... | 2020 | 32955613 |
| effect of 158 herbal remedies on human trpv1 and the two-pore domain potassium channels kcnk2, 3 and 9. | herbal medicines are used to treat a broad number of maladies. however, the pharmacological profile of most remedies is poorly understood. we investigated the effect of herbal remedies from kampo, traditional chinese medicine (tcm) and other phytotherapies on human two-pore domain potassium channels (kcnk channels; trek-1, task-1 and task-3) as well as the human trpv1 channel. kcnk channels are responsible for the background potassium current of excitable cells, thus essential for the maintenanc ... | 2020 | 32953560 |