| targeted pathway-based in vivo testing using thyroperoxidase inhibition to evaluate plasma thyroxine as a surrogate metric of metamorphic success in model amphibian xenopus laevis. | chemical safety evaluation is in the midst of a transition from traditional whole-animal toxicity testing to molecular pathway-based in vitro assays and in silico modeling. however, to facilitate the shift in reliance on apical effects for risk assessment to predictive surrogate metrics having characterized linkages to chemical mechanisms of action, targeted in vivo testing is necessary to establish these predictive relationships. in this study, we demonstrate a means to predict thyroid-related ... | 2020 | 32176285 |
| ssrp1-mediated histone h1 eviction promotes replication origin assembly and accelerated development. | in several metazoans, the number of active replication origins in embryonic nuclei is higher than in somatic ones, ensuring rapid genome duplication during synchronous embryonic cell divisions. high replication origin density can be restored by somatic nuclear reprogramming. however, mechanisms underlying high replication origin density formation coupled to rapid cell cycles are poorly understood. here, using xenopus laevis, we show that ssrp1 stimulates replication origin assembly on somatic ch ... | 2020 | 32165637 |
| evaluation of effective and practical euthanasia methods for larval african clawed frogs (xenopus laevis). | larval, or tadpole-stage xenopus laevis frogs are a popular research model for developmental biology and disease studies. existing euthanasia guidance documents offer recommendations for both eggs and adult stages, yet do not specifically address the larval stage. data evaluating effective euthanasia methods for groups of x. laevis tadpoles would therefore be useful. the goal of the current study was to evaluate the efficacy of various immersion euthanasia procedures on tadpoles: tricaine methan ... | 2020 | 32164797 |
| amphibian thalamic nuclear organization during larval development and in the adult frog xenopus laevis: genoarchitecture and hodological analysis. | the early patterning of the thalamus during embryonic development defines rostral and caudal progenitor domains, which are conserved from fishes to mammals. however, the subsequent developmental mechanisms that lead to the adult thalamic configuration have only been investigated for mammals and other amniotes. in this study, we have analyzed in the anuran amphibian xenopus laevis (an anamniote vertebrate), through larval and postmetamorphic development, the progressive regional expression of spe ... | 2020 | 32162311 |
| rapid shifts in the temperature dependence of locomotor performance in an invasive frog, xenopus laevis, implications for conservation. | temperature is a critical abiotic factor impacting all aspects of the biology of organisms, especially in ectotherms. as such, it is an important determinant of the potential invasive ability of organisms and may limit population expansion unless organisms can physiologically respond to changes in temperature either through plasticity or by adapting to their novel environment. here, we studied the african clawed frog, xenopus laevis, which has become invasive on a global scale. we compared adult ... | 2020 | 32159752 |
| reversible thiol oxidation inhibits the mitochondrial atp synthase in xenopus laevis oocytes. | oocytes are postulated to repress the proton pumps (e.g., complex iv) and atp synthase to safeguard mitochondrial dna homoplasmy by curtailing superoxide production. whether the atp synthase is inhibited is, however, unknown. here we show that: oligomycin sensitive atp synthase activity is significantly greater (~170 vs. 20 nmol/min-1/mg-1) in testes compared to oocytes in xenopus laevis (x. laevis). since atp synthase activity is redox regulated, we explored a regulatory role for reversible thi ... | 2020 | 32150908 |
| fluorescent calcium imaging and subsequent in situ hybridization for neuronal precursor characterization in xenopus laevis. | spontaneous intracellular calcium activity can be observed in a variety of cell types and is proposed to play critical roles in a variety of physiological processes. in particular, appropriate regulation of calcium activity patterns during embryogenesis is necessary for many aspects of vertebrate neural development, including proper neural tube closure, synaptogenesis, and neurotransmitter phenotype specification. while the observation that calcium activity patterns can differ in both frequency ... | 2020 | 32150168 |
| quantitative capillary zone electrophoresis-mass spectrometry reveals the n-glycome developmental plan during vertebrate embryogenesis. | glycans are known to be involved in many biological processes, while little is known about the expression of n-glycans during vertebrate development. we now report the first quantitative studies of both the expression of n-linked glycans at six early development stages and the expression of n-glycosylated peptides at two early development stages in xenopus laevis, the african clawed frog. n-glycans were labeled with isobaric tandem mass tags, pooled, separated by capillary electrophoresis, and c ... | 2020 | 32149324 |
| testing for thyroid hormone disruptors, a review of non-mammalian in vivo models. | thyroid hormones (ths) play critical roles in profound changes in many vertebrates, notably in mammalian neurodevelopment, although the precise molecular mechanisms of these fundamental biological processes are still being unravelled. environmental and health concerns prompted the development of chemical safety testing and, in the context of endocrine disruption, identification of thyroid hormone axis disrupting chemicals (thadcs) remains particularly challenging. as various molecules are known ... | 2020 | 32147522 |
| recent progress of in-cell nmr of nucleic acids in living human cells. | the inside of living cells is highly crowded with biological macromolecules. it has long been considered that the properties of nucleic acids and proteins, such as their structures, dynamics, interactions, and enzymatic activities, in intracellular environments are different from those under in vitro dilute conditions. in-cell nmr is a robust and powerful method used in the direct measurement of those properties in living cells. however, until 2 years ago, in-cell nmr was limited to xenopus laev ... | 2020 | 32144741 |
| miniaturized filter-aided sample preparation (micro-fasp) method for high throughput, ultrasensitive proteomics sample preparation reveals proteome asymmetry in xenopus laevis embryos. | we report a miniaturized filter aided sample preparation method (micro-fasp) for low-loss preparation of submicrogram proteomic samples. the method employs a filter with ∼0.1 mm2 surface area, reduces the total volume of reagents to <10 μl, and requires only two sample transfer steps. the method was used to generate 25 883 unique peptides and 3069 protein groups from 1000 mcf-7 cells (∼100 ng protein content), and 13 367 peptides and 1895 protein groups were identified from 100 mcf-7 cells (∼10 ... | 2020 | 32125139 |
| activation of mouse nbce1-b by xenopus laevis and mouse irbits: role of the variable nt appendage of irbits. | the ip3 receptor binding protein released with inositol 1,4,5-trisphosphate (irbit) plays important roles in the regulation of intracellular ca2+ signaling and intracellular ph. the mammals express two irbit paralogs, i.e., irbit1 (encoded by ahcyl1) and irbit2 (encoded by ahcyl2). the clawed frog xenopus laevis oocyte is widely used for biophysical studies on ion channels and transporters. it remains unknown whether endogenous irbit is expressed in xenopus oocytes. here, we cloned from frog ooc ... | 2020 | 32119862 |
| chromatin accessibility and histone acetylation in the regulation of competence in early development. | as development proceeds, inductive cues are interpreted by competent tissues in a spatially and temporally restricted manner. while key inductive signaling pathways within competent cells are well-described at a molecular level, the mechanisms by which tissues lose responsiveness to inductive signals are not well understood. localized activation of wnt signaling before zygotic gene activation in xenopus laevis leads to dorsal development, but competence to induce dorsal genes in response to wnts ... | 2020 | 32119833 |
| regeneration enhancers: a clue to reactivation of developmental genes. | during tissue and organ regeneration, cells initially detect damage and then alter nuclear transcription in favor of tissue/organ reconstruction. until recently, studies of tissue regeneration have focused on the identification of relevant genes. these studies show that many developmental genes are reused during regeneration. concurrently, comparative genomics studies have shown that the total number of genes does not vastly differ among vertebrate taxa. moreover, functional analyses of developm ... | 2020 | 32096563 |
| microtubule minus-end binding protein camsap2 and kinesin-14 motor kifc3 control dendritic microtubule organization. | neuronal dendrites are characterized by an anti-parallel microtubule organization. the mixed oriented microtubules promote dendrite development and facilitate polarized cargo trafficking; however, the mechanism that regulates dendritic microtubule organization is still unclear. here, we found that the kinesin-14 motor kifc3 is important for organizing dendritic microtubules and to control dendrite development. the kinesin-14 motor proteins (drosophila melanogaster ncd, saccharomyces cerevisiae k ... | 2020 | 32084403 |
| stem cell development involves divergent thyroid hormone receptor subtype expression and epigenetic modifications in the xenopus metamorphosing intestine. | in the intestine during metamorphosis of the frog xenopus laevis, most of the larval epithelial cells are induced to undergo apoptosis by thyroid hormone (th), and under continued th action, the remaining epithelial cells dedifferentiate into stem cells (scs), which then newly generate an adult epithelium analogous to the mammalian intestinal epithelium. previously, we have shown that the precursors of the scs that exist in the larval epithelium as differentiated absorptive cells specifically ex ... | 2020 | 32084349 |
| 14-3-3 targets keratin intermediate filaments to mechanically sensitive cell-cell contacts. | intermediate filament (if) cytoskeletal networks simultaneously support mechanical integrity and influence signal transduction pathways. marked remodeling of the keratin if network accompanies collective cellular morphogenetic movements that occur during early embryonic development in the frog xenopus laevis. while this reorganization of keratin is initiated by force transduction on cell-cell contacts mediated by c-cadherin, the mechanism by which keratin filament reorganization occurs remains p ... | 2020 | 32074004 |
| relationship between the induced iron overload model and hepatic erythropoiesis in xenopus laevis. | iron is an essential element for hemoglobin synthesis during erythropoiesis. iron overload, in contrast, adversely affects erythropoiesis and causes organ dysfunction. research using various animal models may help to elucidate pathophysiological mechanisms induced by excess iron. in the present study, we evaluated the relationship between iron metabolism and erythropoietic activity in the african clawed frog, xenopus laevis. in x. laevis, both erythropoiesis and iron metabolism occur in the live ... | 2020 | 32068375 |
| ashwin gene expression profiles in oocytes, preimplantation embryos, and fetal and adult bovine tissues. | the ashwin gene, originally identified in xenopuslaevis, was found to be expressed first in the neural plate and later in the embryonic brain, eyes, and spinal cord. functional studies of ashwin suggest that it participates in cell survival and anteroposterior patterning. furthermore, ashwin is expressed zygotically in this species, which suggests that it participates in embryonic development. nevertheless, the expression of this gene has not been studied in mammals. thus, the aim of this study ... | 2020 | 32054057 |
| ncbp2 modulates neurodevelopmental defects of the 3q29 deletion in drosophila and xenopus laevis models. | the 1.6 mbp deletion on chromosome 3q29 is associated with a range of neurodevelopmental disorders, including schizophrenia, autism, microcephaly, and intellectual disability. despite its importance towards neurodevelopment, the role of individual genes, genetic interactions, and disrupted biological mechanisms underlying the deletion have not been thoroughly characterized. here, we used quantitative methods to assay drosophila melanogaster and xenopus laevis models with tissue-specific individu ... | 2020 | 32053595 |
| interactions of deet and novel repellents with mosquito odorant receptors. | the carboxamide n,n-di-ethyl-meta-toluamide (deet) is the most effective and widely used insect repellent today. however, drawbacks concerning the efficacy and the safety of the repellent have led to efforts to design new classes of insect repellents. through quantitative structure-activity relationships, chemists have discovered two chemical groups of novel repellents: the acylpiperidines and the carboxamides, with the acylpiperidines generally more potent in biological assays. although the exa ... | 2020 | 32048720 |
| chlorpromazine binding to the pas domains uncovers the effect of ligand modulation on eag channel activity. | ether-a-go-go (eag) potassium selective channels are major regulators of neuronal excitability and cancer progression. eag channels contain a per-arnt-sim (pas) domain in their intracellular n-terminal region. the pas domain is structurally similar to the pas domains in non-ion channel proteins, where these domains frequently function as ligand-binding domains. despite the structural similarity, it is not known whether the pas domain can regulate eag channel function via ligand binding. here, us ... | 2020 | 32047112 |
| 2,2',4,4'-tetrabromodipheny ether (bde-47) disrupts gonadal development of the africa clawed frog (xenopus laevis). | previous studies have shown that bde-47, one of the most abundant polybrominated diphenyl ethers (pbdes) congeners, has a weak estrogenic activity, but it has remained unclear whether bde-47 disrupts gonadal development and causes male-to-female sex reversal in lower vertebrates, with limited and controversial data. the present study aimed to determine the effects of bde-47 on gonadal development in xenopus laevis, a model amphibian species for studying adverse effects of estrogenic chemicals on ... | 2020 | 32045789 |
| the grapevine nae sodium exclusion locus encodes sodium transporters with diverse transport properties and localisation. | grapevine (vitis vinifera l.) is a valuable crop for human consumption and wine production, and is prone to suffering from salinity stress in arid regions or when exposed to low quality irrigation water. a previous study identified a quantitative trait locus (qtl) nae, containing six high-affinity potassium transporter 1 genes, that was associated with shoot na+ exclusion in grapevine. while hkt1;1 was predicted to be the most likely gene within this qtl to encode for this important salinity tol ... | 2020 | 32044673 |
| all-fibre supercontinuum laser for in vivo multispectral photoacoustic microscopy of lipids in the extended near-infrared region. | among the numerous endogenous biological molecules, information on lipids is highly coveted for understanding both aspects of developmental biology and research in fatal chronic diseases. due to the pronounced absorption features of lipids in the extended near-infrared region (1650-1850 nm), visualisation and identification of lipids become possible using multi-spectral photoacoustic (optoacoustic) microscopy. however, the spectroscopic studies in this spectral region require lasers that can pro ... | 2020 | 32042589 |
| multistep peripherin-2/rds self-assembly drives membrane curvature for outer segment disk architecture and photoreceptor viability. | rod and cone photoreceptor outer segment (os) structural integrity is essential for normal vision; disruptions contribute to a broad variety of retinal ciliopathies. oss possess many hundreds of stacked membranous disks, which capture photons and scaffold the phototransduction cascade. although the molecular basis of os structure remains unresolved, recent studies suggest that the photoreceptor-specific tetraspanin, peripherin-2/rds (p/rds), may contribute to the highly curved rim domains at dis ... | 2020 | 32041874 |
| low concentrations of tetrabromobisphenol a disrupt notch signaling and intestinal development in in vitro and in vivo models. | tetrabromobisphenol a (tbbpa) was recently reported to upregulate notch target gene expression in embryonic stem cells differentiating to neurons in vitro, implying activation on notch signaling, a crucial signaling involved in multiple organ development and homeostasis.the present study aimed to determine whether tbbpa at low concentrations can disrupt notch signaling in the intestine and subsequently its development using in vitro and in vivo models, given tbbpa uptake mainly via the intestine ... | 2020 | 32041402 |
| myelopoiesis of the amphibian xenopus laevis is segregated to the bone marrow, away from their hematopoietic peripheral liver. | across vertebrates, hematopoiesis takes place within designated tissues, wherein committed myeloid progenitors further differentiate toward cells with megakaryocyte/erythroid potential (mep) or those with granulocyte/macrophage potential (gmp). while the liver periphery (lp) of the xenopus laevis amphibian functions as a principal site of hematopoiesis and contains meps, cells with gmp potential are instead segregated to the bone marrow (bm) of this animal. presently, using gene expression and w ... | 2019 | 32038608 |
| antiarrhythmic properties of ranolazine: inhibition of atrial fibrillation associated task-1 potassium channels. | background: atrial fibrillation (af) is the most common sustained cardiac arrhythmia and one of the major causes of cardiovascular morbidity and mortality. despite good progress within the past years, safe and effective treatment of af remains an unmet clinical need. the anti-anginal agent ranolazine has been shown to exhibit antiarrhythmic properties via mainly late ina and ikr blockade. this results in prolongation of the atrial action potential duration (apd) and effective refractory period ( ... | 2019 | 32038227 |
| bringing immersive science to undergraduate laboratory courses using crispr gene knockouts in frogs and butterflies. | the use of crispr/cas9 for gene editing offers new opportunities for biology students to perform genuine research exploring the gene-to-phenotype relationship. it is important to introduce the next generation of scientists, health practitioners and other members of society to the technical and ethical aspects of gene editing. here, we share our experience leading hands-on undergraduate laboratory classes, where students formulate hypotheses regarding the roles of candidate genes involved in deve ... | 2020 | 32034043 |
| annexin a3 is necessary for parallel artery-vein alignment in the mouse retina. | annexin a3 (anxa3) is a member of the calcium-regulated, cell membrane-binding family of annexin proteins. we previously confirmed that anxa3 is expressed in the endothelial lineage in vertebrates and that loss of anxa3 in xenopus laevis leads to embryonic blood vessel defects. however, the biological function of anxa3 in mammals is completely unknown. in order to investigate anxa3 vascular function in mammals, we generated an endothelial cell-specific anxa3 conditional knockout mouse model (anx ... | 2020 | 32020697 |
| a novel calcium-activated potassium channel controls membrane potential and intracellular ph in trypanosoma cruzi. | trypanosoma cruzi develops in environments where nutrient availability, osmolarity, ionic concentrations, and ph undergo significant changes. the ability to adapt and respond to such conditions determines the survival and successful transmission of t. cruzi. ion channels play fundamental roles in controlling physiological parameters that ensure cell homeostasis by rapidly triggering compensatory mechanisms. combining molecular, cellular and electrophysiological approaches we have identified and ... | 2019 | 32010643 |
| human cationic amino acid transporters are not affected by direct nitros(yl)ation. | a direct inhibiting effect of no on the function of cat-1 and -2a has been postulated to occur via nitrosylation of cysteine residues in the transporters. neither the no donor snap nor a mixture of sin-1 and spermine nonoate, that generates the strong nitrosating agent n2o3, reduced cat-mediated l-arginine transport. direct nitros(yl)ation does either not occur in cats or does not affect their transport function. a regulatory effect of no or nitrosating agents on cat-mediated transport under phy ... | 2020 | 32008093 |
| structural basis of the fanconi anemia-associated mutations within the fanca and fancg complex. | monoubiquitination of the fanconi anemia complementation group d2 (fancd2) protein by the fa core ubiquitin ligase complex is the central event in the fa pathway. fanca and fancg play major roles in the nuclear localization of the fa core complex. mutations of these two genes are the most frequently observed genetic alterations in fa patients, and most point mutations in fanca are clustered in the c-terminal domain (ctd). to understand the basis of the fa-associated fanca mutations, we determine ... | 2020 | 32002546 |
| tectal crfr1 receptor involvement in avoidance and approach behaviors in the south african clawed frog, xenopus laevis. | animals in the wild must balance food intake with vigilance for predators in order to survive. the optic tectum plays an important role in the integration of external (predators) and internal (energy status) cues related to predator defense and prey capture. however, the role of neuromodulators involved in tectal sensorimotor processing is poorly studied. recently we showed that tectal crfr1 receptor activation decreases food intake in the south african clawed frog, xenopus laevis, suggesting th ... | 2020 | 32001211 |
| cav2.1 c-terminal fragments produced in xenopus laevis oocytes do not modify the channel expression and functional properties. | the sequence and genomic organization of the cacna1a gene that encodes the cav2.1 subunit of both p and q-type ca2+ channels are well conserved in mammals. in human, rat and mouse cacna1a, the use of an alternative acceptor site at the exon 46-47 boundary results in the expression of a long cav2.1 splice variant. in transfected cells, the long isoform of human cav2.1 produces a c-terminal fragment, but it is not known whether this fragment affects cav2.1 expression or functional properties. here ... | 2020 | 31981388 |
| subcellular localization of the tff peptides xp1 and xp4 in the xenopus laevis gastric/esophageal mucosa: different secretion modes reflecting diverse protective functions. | the tff peptides xp1 and xp4 from xenopus laevis are orthologs of tff1 and tff2, respectively. xp1 is secreted as a monomer from gastric surface mucous cells and is generally not associated with mucins, whereas xp4 is a typical secretory peptide from esophageal goblet cells, and gastric mucous neck and antral gland cells tightly associated as a lectin with the ortholog of mucin muc6. both tff peptides have diverse protective functions, xp1 as a scavenger for reactive oxygen species preventing ox ... | 2020 | 31979419 |
| expression of α3β2β4 nicotinic acetylcholine receptors by rat adrenal chromaffin cells determined using novel conopeptide antagonists. | adrenal chromaffin cells release neurotransmitters in response to stress and may be involved in conditions such as post-traumatic stress and anxiety disorders. neurotransmitter release is triggered, in part, by activation of nicotinic acetylcholine receptors (nachrs). however, despite decades of use as a model system for studying exocytosis, the nachr subtypes involved have not been pharmacologically identified. quantitative real-time pcr of rat adrenal medulla revealed an abundance of mrnas for ... | 2020 | 31967330 |
| hydrogen sulfide impairs meiosis resumption in xenopuslaevis oocytes. | the role of hydrogen sulfide (h2s) is addressed in xenopuslaevis oocytes. three enzymes involved in h2s metabolism, cystathionine β-synthase, cystathionine γ-lyase, and 3-mercaptopyruvate sulfurtransferase, were detected in prophase i and metaphase ii-arrested oocytes and drove an acceleration of oocyte meiosis resumption when inhibited. moreover, meiosis resumption is associated with a significant decrease in endogenous h2s. on another hand, a dose-dependent inhibition was obtained using the h2 ... | 2020 | 31963573 |
| convergent extension in the amphibian, xenopus laevis. | this review is a comprehensive analysis of the cell biology and biomechanics of convergent extension in xenopus. | 2020 | 31959291 |
| biochemical reconstitution of branching microtubule nucleation. | microtubules are nucleated from specific locations at precise times in the cell cycle. however, the factors that constitute these microtubule nucleation pathways and their mode of action still need to be identified. using purified xenopus laevis proteins we biochemically reconstitute branching microtubule nucleation, which is critical for chromosome segregation. we found that besides the microtubule nucleator gamma-tubulin ring complex (γ-turc), the branching effectors augmin and tpx2 are requir ... | 2020 | 31933480 |
| developmental and lethal effects of glyphosate and a glyphosate-based product on xenopus laevis embryos and tadpoles. | effects of pure glyphosate and a glyphosate-based product were evaluated comparatively using two embryonic development stages of xenopus laevis as model system. when pure glyphosate was applied in ph adjusted media, lethal or developmental effects were not observed at concentrations up to 500 mg l-1. the 96 h lc50 values for the commercial herbicide, in contrast, were 32.1 and 35.1 mg active ingredient l-1 for embryos and tadpoles, respectively. since pure glyphosate has no effect on the selecte ... | 2020 | 31932905 |
| reciprocal matched filtering in the inner ear of the african clawed frog (xenopus laevis). | anurans (frogs and toads) are the most vocal amphibians. in most species, only males produce advertisement calls for defending territories and attracting mates. female vocalizations are the exceptions among frogs, however in the african clawed frog (xenopus laevis) both males and females produce distinct vocalizations. the matched filter hypothesis predicts a correspondence between peripheral auditory tuning of receivers and properties of species-specific acoustic signals, but few studies have a ... | 2020 | 31907715 |
| xenopus embryos show a compensatory response following perturbation of the notch signaling pathway. | as an essential feature of development, robustness ensures that embryos attain a consistent phenotype despite genetic and environmental variation. the growing number of examples demonstrating that embryos can mount a compensatory response to germline mutations in key developmental genes has heightened interest in the phenomenon of embryonic robustness. while considerable progress has been made in elucidating genetic compensation in response to germline mutations, the diversity, mechanisms, and l ... | 2020 | 31899211 |
| generation, coordination, and evolution of neural circuits for vocal communication. | in many species, vocal communication is essential for coordinating social behaviors including courtship, mating, parenting, rivalry, and alarm signaling. effective communication requires accurate production, detection, and classification of signals, as well as selection of socially appropriate responses. understanding how signals are generated and how acoustic signals are perceived is key to understanding the neurobiology of social behaviors. here we review our long-standing research program foc ... | 2020 | 31896561 |
| genome-wide analysis identifies cis-acting elements regulating mrna polyadenylation and translation during vertebrate oocyte maturation. | most cells change patterns of gene expression through transcriptional regulation. in contrast, oocytes are transcriptionally silent and regulate mrna poly(a) tail length to control protein production. however, the genome-wide relationship of poly(a) tail changes to mrna translation during vertebrate oocyte maturation is not known. we used tail-seq and polyribosome analysis to measure poly(a) tail and translational changes during oocyte maturation in xenopus laevis we identified large-scale poly( ... | 2020 | 31896558 |
| the peptide transporter 1a of the zebrafish danio rerio, an emerging model in nutrigenomics and nutrition research: molecular characterization, functional properties, and expression analysis. | peptide transporter 1 (pept1, alias slc15a1) mediates the uptake of dietary di/tripeptides in all vertebrates. however, in teleost fish, more than one pept1-type transporter might function, due to specific whole genome duplication event(s) that occurred during their evolution leading to a more complex paralogue gene repertoire than in higher vertebrates (tetrapods). | 2019 | 31890051 |
| the influence of long-term cadmium exposure on the male advertisement call of xenopus laevis. | cadmium (cd) is a non-essential environmental endocrine-disrupting compound found in water and a potential threat to aquatic habitats. cd has been shown to have various short-term effects on aquatic animals; however, evidence for long-term effects of cd on vocal communications in amphibians is lacking. to better understand the long-term effects of low-dose cd on acoustic communication in amphibians, male xenopus laevis individuals were treated with low cd concentrations (0.1, 1, and 10 μg/l) via ... | 2020 | 31889288 |
| several phosphate transport processes are present in vascular smooth muscle cells. | we have studied inorganic phosphate (pi) handling in rat aortic vascular smooth muscle cells (vsmc) using 32p-radiotracer assays. our results have revealed a complex set of mechanisms consisting of 1) well-known pit1/pit2-mediated sodium-dependent pi transport; 2) slc20-unrelated sodium-dependent pi transport that is sensitive to the stilbene derivatives 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid (dids) and 4-acetamido-4-isothiocyanostilbene-2,2-disulfonate (sits); 3) a sodium-independe ... | 2020 | 31886722 |
| prominin-1 and photoreceptor cadherin localization in xenopus laevis: protein-protein relationships and function. | retinal degenerative diseases are genetically diverse and rare inherited disorders that cause the death of rod and cone photoreceptors, resulting in progressive vision loss and blindness. this review will focus on two retinal degeneration-causing genes: prominin-1 (prom1) and photoreceptor cadherin (prcad). we will discuss protein localization, potential roles in photoreceptor outer segment disc morphogenesis, and areas for future investigation. | 2019 | 31884658 |
| autophagy induction by hdac inhibitors is unlikely to be the mechanism of efficacy in prevention of retinal degeneration caused by p23h rhodopsin. | we previously found that valproic acid (vpa) and other histone deacetylase inhibitors (hdacis) ameliorate retinal degeneration (rd) caused by p23h rhodopsin in xenopus laevis larvae and hypothesized that this may be due to enhancement of autophagy. here we use x. laevis expressing an autophagy marker to assess effects of hdacis on autophagy. we also assess the effects of non-hdaci activators and inducers of autophagy on rd caused by p23h rhodopsin. | 2019 | 31884645 |
| active emigration from climate change-caused seawater intrusion into freshwater habitats. | ecological risk assessment associated with seawater intrusions has been supported on the determination of lethal/sublethal effects following standard protocols that force exposure neglecting the ability of mobile organisms to spatially avoid salinized environments. thus, this work aimed at assessing active emigration from climate change-caused seawater intrusion into freshwater habitats. to specific objectives were delineated: first, to compute median 12-h avoidance conductivities (ac50,12h) for ... | 2020 | 31883492 |
| heparan sulfate proteoglycans regulate bmp signalling during neural crest induction. | bone morphogenetic protein (bmp) signalling is key to many developmental processes, including early regionalisation of the ectoderm. the neural crest is induced here by a combination of bmp and wnt signals from nearby tissues with many secreted factors contributing to its initial specification at the neural plate border. gremlin 1 (grem1) is a secreted bmp antagonist expressed in the neural crest in xenopus laevis but its function here is unknown. as well as binding bmps, grem1 has been shown to ... | 2020 | 31883440 |
| expression and ion transport activity of rice oshkt1;1 variants. | oshkt1;1 in rice, belongs to the high-affinity k+ transporter family, has been found to be involved in salt tolerance. oshkt1;1 in japonica rice (nipponbare) produces mrna variants, but their functions remain elusive. in salt tolerant rice, pokkali, eight oshkt1;1 variants (v1-v8) were identified in addition to the full-length oshkt1;1 (fl) cdna. absolute quantification by qpcr revealed that accumulation of oshkt1;1-fl mrna is minor in contrast to that of oshkt1;1-v1, -v2, -v4, and -v7 mrnas, al ... | 2019 | 31877741 |
| distinct m6a methylome profiles in poly(a) rna from xenopus laevis testis and that treated with atrazine. | recent discovery of reversible n6-methyladenosine (m6a) methylation on messenger rna (mrna) and mapping of m6a methylomes in mammals, plant and yeast revealed potential regulatory functions of this rna modification. however, the role of the m6a methylomes in amphibious is still poorly understood. here, we examined the m6a transcriptome-wide profile in testis tissues of xenopus laevis (x. laevis) with and without treatment with 100 μg/l atrazine (az) through m6a sequencing analysis using the late ... | 2020 | 31877456 |
| transformation of receptor tyrosine kinases into glutamate receptors and photoreceptors. | receptor tyrosine kinases (rtks) are key regulators of cellular functions in metazoans. in vertebrates, rtks are mostly activated by polypeptides but are not naturally sensitive to amino acids or light. taking inspiration from venus kinase receptors (vkrs), an atypical family of rtks found in nature, we have transformed the human insulin (hir) and hepatocyte growth factor receptor (hmet) into glutamate receptors by replacing their extracellular binding domains with the ligand-binding domain of m ... | 2020 | 31872568 |
| modeling ocular lens disease in xenopus. | ocular lens clouding is termed as cataract, which depending on the onset, is classified as congenital or age-related. developing new cataract treatments requires new models. thus far, xenopus embryos have not been evaluated as a system for studying cataract. | 2020 | 31872467 |
| bupropion inhibits serotonin type 3ab heteromeric channels at clinically relevant concentrations. | bupropion, a food and drug administration-approved antidepressant and smoking cessation aid, blocks dopamine and norepinephrine reuptake transporters and noncompetitively inhibits nicotinic acetylcholine and serotonin (5-ht) type 3a receptors (5-ht3ars). 5-ht3 receptors are pentameric ligand-gated ion channels that regulate synaptic activity in the central and peripheral nervous system, presynaptically and postsynaptically. in the present study, we examined and compared the effect of bupropion a ... | 2020 | 31871303 |
| the γ-hydroxybutyric acid (ghb) analogue ncs-382 is a substrate for both monocarboxylate transporters subtypes 1 and 4. | the small-molecule ligand (e)-2-(5-hydroxy-5,7,8,9-tetrahydro-6h-benzo[7]annulen-6-ylidene)acetic acid (ncs-382) is an analogue of γ-hydroxybutyric acid (ghb) and is widely used for probing the brain-specific ghb high-affinity binding sites. to reach these, brain uptake is imperative, and it is therefore important to understand the molecular mechanisms of ncs-382 transport in order to direct in vivo studies. in this study, we hypothesized that ncs-382 is a substrate for the monocarboxylate trans ... | 2020 | 31866563 |
| applying tensile and compressive force to xenopus animal cap tissue. | over many years, the xenopus laevis embryo has provided a powerful model system to investigate how mechanical forces regulate cellular function. here, we describe a system to apply reproducible tensile and compressive force to x. laevis animal cap tissue explants and to simultaneously assess cellular behavior using live confocal imaging. | 2020 | 31857437 |
| insights into the assembly and activation of the microtubule nucleator γ-turc. | microtubules are dynamic polymers of α- and β-tubulin and have crucial roles in cell signalling, cell migration, intracellular transport and chromosome segregation1. they assemble de novo from αβ-tubulin dimers in an essential process termed microtubule nucleation. complexes that contain the protein γ-tubulin serve as structural templates for the microtubule nucleation reaction2. in vertebrates, microtubules are nucleated by the 2.2-megadalton γ-tubulin ring complex (γ-turc), which comprises γ-t ... | 2020 | 31856152 |
| organ-specific requirements for thyroid hormone receptor ensure temporal coordination of tissue-specific transformations and completion of xenopus metamorphosis. | background: thyroid hormone (triiodothyronine [t3]) is essential for the development throughout vertebrates. anuran metamorphosis mimics mammalian postembryonic development, a period around birth when plasma t3 level peaks and many organs/tissues mature into their adult forms. compared with the uterus-enclosed mammalian embryos, tadpoles can be easily manipulated to study the roles of t3 and t3 receptors (trs) in tissue remodeling and adult organ development. we and others have previously knocke ... | 2020 | 31854240 |
| characterization of spinal cord damage based on automatic video analysis of froglet swimming. | xenopus laevis frogs are a widely used organism to study aspects of modern biology ( harland and grainger, 2011). its central nervous system is particularly interesting, because in certain stages of metamorphosis the spinal cord can regenerate after injury and recover swimming. with this in mind, automatic gait analysis could help evaluate the regenerative performance by means of a method that automatically and quantitatively establishes the degree in froglets' limb movement. here, we present an ... | 2019 | 31852668 |
| endoplasmic reticulum transmembrane protein tmtc3 contributes to o-mannosylation of e-cadherin, cellular adherence, and embryonic gastrulation. | protein glycosylation plays essential roles in protein structure, stability, and activity such as cell adhesion. the cadherin superfamily of adhesion molecules carry o-linked mannose glycans at conserved sites and it was recently demonstrated that the transmembrane and tetratricopeptide repeat-containing proteins 1-4 (tmtc1-4) gene products contribute to the addition of these o-linked mannoses. here, biochemical, cell biological, and organismal analysis was used to determine that tmtc3 supports ... | 2020 | 31851597 |
| desensitization of nmda channels requires ligand binding to both glun1 and glun2 subunits to constrict the pore beside the activation gate. | n-methyl-d-aspartate (nmda) receptor channels are activated by glutamate (or nmda) and glycine. the channels also undergo desensitization, which denotes decreased channel availability, after prolonged exposure to the activating ligands. glycine apparently has a paradoxical negative effect on desensitization, as the increase in ambient glycine in concentrations required for channel activation would increase sustained nmda receptor currents. we hypothesized that this classical "glycine-dependent d ... | 2020 | 31821563 |
| the chalcone lonchocarpin inhibits wnt/β-catenin signaling and suppresses colorectal cancer proliferation. | the deregulation of the wnt/β-catenin signaling pathway is a central event in colorectal cancer progression, thus a promising target for drug development. many natural compounds, such as flavonoids, have been described as wnt/β-catenin inhibitors and consequently modulate important biological processes like inflammation, redox balance, cancer promotion and progress, as well as cancer cell death. in this context, we identified the chalcone lonchocarpin isolated from lonchocarpus sericeus as a wnt ... | 2019 | 31817828 |
| d-glucuronolactone attenuates para-xylene-induced defects in neuronal development and plasticity in xenopus tectum in vivo. | xylene and its derivatives are known to be neurotoxic to the central nervous system of animals. our previous work has shown that para-xylene (px) can cause an increase in apoptotic cells and abnormal avoidance behavior in xenopus laevis. however, the mechanism underlying the impact of px on neuronal structural and functional plasticity is less clear. here, we examined the effects of px on neuronal development and plasticity in the developing optic tectum. we found that huc/d-positive neurons wer ... | 2020 | 31811891 |
| analysis of clcnkb mutations at dimer-interface, calcium-binding site, and pore reveals a variety of functional alterations in clc-kb channel leading to bartter syndrome. | pathological missense mutations in clcnkb gene give a wide spectrum of clinical phenotypes in bartter syndrome type iii patients. molecular analysis of the mutated clc-kb channels can be helpful to classify the mutations according to their functional alteration. we investigated the functional consequences of nine mutations in the clcnkb gene causing bartter syndrome. we first established that all tested mutations lead to decreased clc-kb currents. combining electrophysiological and biochemical m ... | 2020 | 31803959 |
| the tff peptides xp1 and xp4 appear in distinctive forms in the xenopus laevis gastric mucosa: indications for different protective functions. | the gastric secretory trefoil factor family (tff) peptides xp1 and xp4 are the xenopus laevis orthologs of mammalian tff1 and tff2, respectively. the aim of this study was to analyze the molecular forms of xp1 and xp4 in the x. laevis gastric mucosa by fplc. xp1 mainly occurred in a monomeric low-molecular-mass form and only a minor subset is associated with the mucus fraction. the occurrence of monomeric xp1 is unexpected because of its odd number of cysteine residues. probably a conserved acid ... | 2019 | 31801293 |
| mathematical model explaining the role of cdc6 in the diauxic growth of cdk1 activity during the m-phase of the cell cycle. | in this paper we propose a role for the cdc 6 protein in the entry of cells into mitosis. this has not been considered in the literature so far. recent experiments suggest that cdc 6 , upon entry into mitosis, inhibits the appearance of active cdk 1 and cyclin b complexes. this paper proposes a mathematical model which incorporates the dynamics of kinase cdk 1 , its regulatory protein cyclin b, the regulatory phosphatase cdc 25 and the inhibitor cdc 6 known to be involved in the regulation of ac ... | 2019 | 31795221 |
| role of trka signaling during tadpole tail regeneration and early embryonic development in xenopus laevis. | neurotrophic signaling regulates neural cell behaviors in development and physiology, although its role in regeneration has not been fully investigated. here, we examined the role of neurotrophic signaling in xenopus laevis tadpole tail regeneration. after the tadpole tails were amputated, the expression of neurotrophin ligand family genes, especially ngf and bdnf, was up-regulated as regeneration proceeded. moreover, notochordal expression of the ngf receptor gene trka, but not that of other ne ... | 2020 | 31788928 |
| studying in vivo retinal progenitor cell proliferation in xenopus laevis. | the efficient generation and maintenance of retinal progenitor cells (rpcs) are key goals needed for developing strategies for productive eye repair. although vertebrate eye development and retinogenesis are well characterized, the mechanisms that can initiate rpc proliferation following injury-induced regrowth and repair remain unknown. this is partly because endogenous rpc proliferation typically occurs during embryogenesis while studies of retinal regeneration have largely utilized adult (or ... | 2020 | 31786778 |
| molecular characterization of the orphan transporter slc16a9, an extracellular ph- and na+-sensitive creatine transporter. | human monocarboxylate transporters (hmcts) mediate the transport of monocarboxylates across plasma membranes. one such transporter, hmct9, has been shown to be related to serum uric acid levels and the risk of renal overload gout. however, the functional characteristics of hmct9 remain unknown. the aim of this study was to investigate the expression and localization of hmct9 using a xenopus laevis oocyte heterologous expression system and characterize its transport properties. kinetic analysis o ... | 2020 | 31784090 |
| a glimpse of the peptide profile presentation by xenopus laevis mhc class i: crystal structure of pxela-uaa reveals a distinct peptide-binding groove. | the african clawed frog, xenopus laevis, is a model species for amphibians. before metamorphosis, tadpoles do not efficiently express the single classical mhc class i (mhc-i) molecule xela-uaa, but after metamorphosis, adults express this molecule in abundance. to elucidate the ag-presenting mechanism of xela-uaa, in this study, the xela-uaa structure complex (pxela-uaag) bound with a peptide from a synthetic random peptide library was determined. the amino acid homology between the xela-uaa and ... | 2020 | 31776204 |
| optimized photo-stimulation of halorhodopsin for long-term neuronal inhibition. | optogenetic silencing techniques have expanded the causal understanding of the functions of diverse neuronal cell types in both the healthy and diseased brain. a widely used inhibitory optogenetic actuator is enphr3.0, an improved version of the light-driven chloride pump halorhodopsin derived from natronomonas pharaonis. a major drawback of enphr3.0 is related to its pronounced inactivation on a time-scale of seconds, which renders it unsuited for applications that require long-lasting silencin ... | 2019 | 31775747 |
| apple almt9 requires a conserved c-terminal domain for malate transport underlying fruit acidity. | malate accumulation in the vacuole largely determines apple (malus domestica) fruit acidity, and low fruit acidity is strongly associated with truncation of ma1, an ortholog of aluminum-activated malate transporter9 (almt9) in arabidopsis (arabidopsis thaliana). a mutation at base 1,455 in the open reading frame of ma1 leads to a premature stop codon that truncates the protein by 84 amino acids at its c-terminal end. here, we report that both the full-length protein, ma1, and its naturally occur ... | 2020 | 31772076 |
| a prototype of the mammalian sulfotransferase 1 (sult1) family in xenopus laevis: molecular and enzymatic properties of xlsult1b.s. | the cytosolic sulfotransferase 1 (sult1) proteins are a family of highly divergent proteins that show variable expansion in different species during vertebrate evolution. to clarify the evolutionary origin of the mammalian lineage of the sult1 family, we compiled xenopus laevis and x. tropicalis sult1 (xsult1) sequences from public databases. the xsult1 family was found to comprise at least six subfamilies, which corresponded in part to five mammalian sult1 subfamilies but only poorly to zebrafi ... | 2019 | 31748465 |
| effect of triadimefon and its metabolite on adult amphibians xenopus laevis. | the decrease in the population of amphibians all over the world has raised concerns. adult x. laevis frogs were exposed to 0, 1 and 10 mg/l triadimefon and triadimenol. after 14 or 28 days exposure, we collected male and female specimens to study swimming activity, lactic dehydrogenase (ldh) and antioxidant enzyme activity in blood samples, histopathology of liver and thyroid tissue, thyroid hormone levels and thyroid hormone-related gene expression levels in brains. our results showed that tria ... | 2020 | 31743868 |
| overexpression of ataap1 increased the uptake of an alanine-chlorantraniliprole conjugate in arabidopsis thaliana. | transporters play an important role in the uptake and redistribution of agrochemicals to the site of insect feeding. the product of the arabidopsis thaliana gene ataap1 substantially contributes to inorganic nitrogen acquisition under ecologically relevant amino acid concentrations. here, the transporter ability of ataap1 to a chlorantraniliprole-alanine conjugate (cap-ala-1) was tested both in planta and in vitro. thirty-day-old and 15-day-old plants overexpressing ataap1 increased the uptake o ... | 2019 | 31741272 |
| ligand binding characteristics of the ku80 von willebrand domain. | the n-terminal von willebrand domain of ku80 supports interactions with a ku binding motif (kbm) that has been identified in at least three other dna repair proteins: the non-homologous end joining (nhej) scaffold aplf, the modulator of retrovirus infection, mri, and the werner syndrome protein (wrn). a second, more recently identified ku binding motif present in xlf and several other proteins (kbmx) has also been reported to interact with this domain. the isolated ku80 von willebrand antigen do ... | 2020 | 31733588 |
| in vitro modeling of batrachochytrium dendrobatidis infection of the amphibian skin. | the largest current disease-induced loss of vertebrate biodiversity is due to chytridiomycosis and despite the increasing understanding of the pathogenesis, knowledge unravelling the early host-pathogen interactions remains limited. batrachochytrium dendrobatidis (bd) zoospores attach to and invade the amphibian epidermis, with subsequent invasive growth in the host skin. availability of an in vitro assay would facilitate in depth study of this interaction while reducing the number of experiment ... | 2019 | 31725762 |
| tomato roots have a functional silicon influx transporter but not a functional silicon efflux transporter. | silicon (si) accumulation in shoots differs greatly with plant species, but the molecular mechanisms for this interspecific difference are unknown. here, we isolated homologous genes of rice si influx (sllsi1) and efflux (sllsi2) transporter genes in tomato (solanum lycopersicum l.) and functionally characterized these genes. sllsi1 showed transport activity for si when expressed in both rice lsi1 mutant and xenopus laevis oocytes. sllsi1 was constitutively expressed in the roots. immunostaining ... | 2020 | 31724184 |
| the flavor enhancer maltol increases pigment aggregation in dermal and neural melanophores in xenopus laevis tadpoles. | melanophores are pigmented cells that change the distribution of melanosomes, enabling animals to appear lighter or darker for camouflage, thermoregulation, and protection from ultraviolet radiation. a complex series of hormonal and neural mechanisms regulates melanophore pigment distribution, making these dynamic cells a valuable tool to screen toxicants as they rapidly respond to changes in the environment. we found that maltol, a naturally occurring flavor enhancer and fragrance agent, induce ... | 2020 | 31721268 |
| iron nanoparticle bio-interactions evaluated in xenopus laevis embryos, a model for studying the safety of ingested nanoparticles. | iron nanoparticles (nps) have been proposed as a tool in very different fields such as environmental remediation and biomedical applications, including food fortification against iron deficiency, even if there is still concern about their safety. here, we propose xenopus laevis embryos as a suitable model to investigate the toxicity and the bio-interactions at the intestinal barrier of fe3o4 and zerovalent iron (zvi) nps compared to fe(ii) and (iii) salts in the 5 to 100 mg fe/l concentration ra ... | 2020 | 31718350 |
| cell type-specific transcriptome analysis unveils secreted signaling molecule genes expressed in apical epithelial cap during appendage regeneration. | wound epidermis (we) and the apical epithelial cap (aec) are believed to trigger regeneration of amputated appendages such as limb and tail in amphibians by producing certain secreted signaling molecules. to date, however, only limited information about the molecular signatures of these epidermal structures is available. here we used a transgenic xenopus laevis line harboring the enhanced green fluorescent protein (egfp) gene under control of an es1 gene regulatory sequence to isolate we/aec cel ... | 2019 | 31713234 |
| toward decoding bioelectric events in xenopus embryogenesis: new methodology for tracking interplay between calcium and resting potentials in vivo. | although chemical signaling during embryogenesis is readily addressed by a plethora of available techniques, the developmental functions of ionic signaling are still poorly understood. it is increasingly realized that bioelectric events in nonneural cells are critical for pattern regulation, but their study has been hampered by difficulties in monitoring and manipulating them in vivo. recent developments in visualizing electrical signaling dynamics in the field of neuroscience have facilitated f ... | 2020 | 31711960 |
| arabidopsis pic30 encodes a major facilitator superfamily transporter responsible for the uptake of picolinate herbicides. | picloram is an auxinic herbicide that is widely used for controlling broad leaf weeds. however, its mechanism of transport into plants is poorly understood. in a genetic screen for picloram resistance, we identified three arabidopsis mutant alleles of pic30 (picloram resistant30) that are specifically resistant to picolinates, but not to other auxins. pic30 is a previously uncharacterized gene that encodes a major facilitator superfamily (mfs) transporter. similar to most members of mfs, pic30 c ... | 2020 | 31710151 |
| serotonin and mucxs release by small secretory cells depend on xpod, a ssc specific marker gene. | mucus secretion and ciliary motility are hallmarks for muco-ciliary epithelia (mce). both, mammalian airways as well as the less complex epidermis of xenopus embryos show cilia-driven mucus flow to protect the organism against harmful effects by exogenous pathogens or pollutants. four cell types set up the epidermal mce in xenopus. multi-ciliated cells (mccs) generate an anterior to posterior flow of mucus. ion secreting cells (iscs) are characterized by the expression of ion transporters, presu ... | 2020 | 31705622 |
| repression of inappropriate gene expression in the vertebrate embryonic ectoderm. | during vertebrate embryogenesis, precise regulation of gene expression is crucial for proper cell fate determination. much of what we know about vertebrate development has been gleaned from experiments performed on embryos of the amphibian xenopus laevis; this review will focus primarily on studies of this model organism. an early critical step during vertebrate development is the formation of the three primary germ layers-ectoderm, mesoderm, and endoderm-which emerge during the process of gastr ... | 2019 | 31698780 |
| pannexin 1 activation and inhibition is permeant-selective. | the large-pore channel pannexin 1 (panx1) is expressed in many cell types and can open upon different, yet not fully established, stimuli. panx1 permeability is often inferred from channel permeability to fluorescent dyes, but it is currently unknown whether dye permeability translates to permeability to other molecules. cell shrinkage and c-terminal cleavage led to a panx1 open-state with increased permeability to atomic ions (current), but did not alter ethidium uptake. panx1 inhibitors affect ... | 2020 | 31698505 |
| the role of nitric oxide during embryonic wound healing. | the study of the mechanisms controlling wound healing is an attractive area within the field of biology, with it having a potentially significant impact on the health sector given the current medical burden associated with healing in the elderly population. healing is a complex process and includes many steps that are regulated by coding and noncoding rnas, proteins and other molecules. nitric oxide (no) is one of these small molecule regulators and its function has already been associated with ... | 2019 | 31694542 |
| trpc1 as the missing link between the bmp and ca2+ signalling pathways during neural specification in amphibians. | in amphibians, the inhibition of bone morphogenetic protein (bmp) in the dorsal ectoderm has been proposed to be responsible for the first step of neural specification, called neural induction. we previously demonstrated that in xenopus laevis embryos, the bmp signalling antagonist, noggin, triggers an influx of ca2+ through voltage-dependent l-type ca2+ channels (ltccs), mainly via cav1.2, and we showed that this influx constitutes a necessary and sufficient signal for triggering the expression ... | 2019 | 31690785 |
| the hkt transporter hvhkt1;5 negatively regulates salt tolerance. | maintaining low intracellular na+ concentrations is an essential physiological strategy in salt stress tolerance in most cereal crops. here, we characterized a member of the high-affinity k+ transporter (hkt) family in barley (hordeum vulgare), hvhkt1;5, which negatively regulates salt tolerance and has different functions from its homology in other cereal crops. hvhkt1;5 encodes a plasma membrane protein localized to root stele cells, particularly in xylem parenchyma cells adjacent to the xylem ... | 2020 | 31690708 |
| simple method to characterize the ciliary proteome of multiciliated cells. | motile cilia of multiciliated epithelial cells have important roles in animal development and cell homeostasis. although several studies have identified and reported proteins localized in this complex organelle and the related immotile primary cilia from various cell types, it is still challenging to isolate high quantities of ciliary proteins for proteomic analysis. in this study, african clawed frog (xenopus laevis) embryos, which have many multiciliated cells in the epidermis, were treated wi ... | 2020 | 31689115 |
| complement c1q subunit molecules from xenopus laevis possess conserved function in c1q-immunoglobulin interaction. | complement component 1q (c1q), together with c1r and c1s to form c1, recognize and bind immune complex to initiate the classical complement pathway. in this study, c1q subunit molecules (xlc1qa, xlc1qb, xlc1qc) were cloned and analyzed from xenopus laevis (x. laevis). the open reading frame (orf) of xlc1qa is 819 bp of nucleotide sequence encoding 272 amino acids, the orf of xlc1qb is 711 bp encoding 236 aa, and the xlc1qc is consists of 732 bp encoding 243 aa. the deduced amino acid sequences c ... | 2020 | 31678076 |
| spontaneous emergence of cell-like organization in xenopus egg extracts. | every daughter cell inherits two things from its mother: genetic information and a spatially organized complement of macromolecular complexes and organelles. the extent to which de novo self-organization, as opposed to inheritance of an already organized state, can suffice to yield functional cells is uncertain. we used xenopus laevis egg extracts to show that homogenized interphase egg cytoplasm self-organizes over the course of ~30 minutes into compartments 300 to 400 micrometers in length tha ... | 2019 | 31672897 |
| single-cell proteomics in complex tissues using microprobe capillary electrophoresis mass spectrometry. | direct measurement of proteins produced by single cells promises to expand our understanding of molecular cell-to-cell differences (heterogeneity) and their contribution to normal and impaired development. high-resolution mass spectrometry (hrms) is the modern technology of choice for the label-free identification and quantification of proteins, albeit usually in large populations of cells. recent advances in microscale sample collection and processing, separation, and ionization have extended t ... | 2019 | 31668233 |
| identification and characterisation of two high-affinity glucose transporters from the spoilage yeast brettanomyces bruxellensis. | the yeast brettanomyces bruxellensis (syn. dekkera bruxellensis) is an emerging and undesirable contaminant in industrial low-sugar ethanol fermentations that employ the yeast saccharomyces cerevisiae. high-affinity glucose import in b. bruxellensis has been proposed to be the mechanism by which this yeast can outcompete s. cerevisiae. the present study describes the characterization of two b. bruxellensis genes (bht1 and bht3) believed to encode putative high-affinity glucose transporters. in v ... | 2019 | 31665273 |
| identification and characterization of the atlantic salmon peptide transporter 1a. | peptide transporter 1 (pept1) mediates the uptake of dietary di-/tripeptides in vertebrates. however, in teleost fish gut, more than one pept1-type transporter might operate, because of teleost-specific whole gen(om)e duplication event(s) that occurred during evolution. here, we describe a novel teleost di-/tripeptide transporter, i.e., the atlantic salmon (salmo salar) peptide transporter 1a [pept1a; or solute carrier family 15 member 1a (slc15a1a)], which is a paralog (77% similarity and 64% i ... | 2020 | 31664857 |
| fluorescence lifetime imaging reveals heterogeneous functional distribution of egfp expressed in xenopus oocytes. | the oocytes from xenopus laevis are well known for their polarity, presenting a distinct animal and vegetal pole. other heterogeneities are less known. to study the heterogeneity of the xenopus oocyte, we expressed egfp and analyzed the protein distribution with fluorescence lifetime microscopy. the vegetal pole exhibited higher levels of fluorescence, than the animal pole. however, the fluorescence lifetimes between the two areas were indistinguishable, suggesting similar environments. in contr ... | 2019 | 31658452 |