Publications

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
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
nutrient restriction causes reversible g2 arrest in xenopus neural progenitors.	nutrient status affects brain development; however, the effects of nutrient availability on neural progenitor cell proliferation in vivo are poorly understood. without food, xenopus laevis tadpoles enter a period of stasis during which neural progenitor proliferation is drastically reduced, but resumes when food becomes available. here, we investigate how neural progenitors halt cell division in response to nutrient restriction and subsequently re-enter the cell cycle upon feeding. we demonstrat ...	2019	31649012
bioinformatics screening of genes specific for well-regenerating vertebrates reveals c-answer, a regulator of brain development and regeneration.	the molecular basis of higher regenerative capacity of cold-blooded animals comparing to warm-blooded ones is poorly understood. although this difference in regenerative capacities is commonly thought to be a result of restructuring of the same regulatory gene network, we hypothesized that it may be due to loss of some genes essential for regeneration. we describe here a bioinformatic method that allowed us to identify such genes. for investigation in depth we selected one of them encoding trans ...	2019	31644900
azi-medetomidine: synthesis and characterization of a novel α2 adrenergic photoaffinity ligand.	agonists at the α2 adrenergic receptor produce sedation, increase focus, provide analgesia, and induce centrally mediated hypotension and bradycardia, yet neither their dynamic interactions with adrenergic receptors nor their modulation of neuronal circuit activity is completely understood. photoaffinity ligands of α2 adrenergic agonists have the potential both to capture discrete moments of ligand-receptor interactions and to prolong naturalistic drug effects in discrete regions of tissue in vi ...	2019	31638765
nucleoplasmin is a limiting component in the scaling of nuclear size with cytoplasmic volume.	how nuclear size is regulated relative to cell size is a fundamental cell biological question. reductions in both cell and nuclear sizes during xenopus laevis embryogenesis provide a robust scaling system to study mechanisms of nuclear size regulation. to test if the volume of embryonic cytoplasm is limiting for nuclear growth, we encapsulated gastrula-stage embryonic cytoplasm and nuclei in droplets of defined volume using microfluidics. nuclei grew and reached new steady-state sizes as a funct ...	2019	31636119
n-glycosylation of trek-1/hk2p2.1 two-pore-domain potassium (k2p) channels.	mechanosensitive htrek-1 two-pore-domain potassium (hk2p2.1) channels give rise to background currents that control cellular excitability. recently, trek-1 currents have been linked to the regulation of cardiac rhythm as well as to hypertrophy and fibrosis. even though the pharmacological and biophysical characteristics of htrek-1 channels have been widely studied, relatively little is known about their posttranslational modifications. this study aimed to evaluate whether htrek-1 channels are n- ...	2019	31635148
an optimized screen reduces the number of ga transporters and provides insights into nitrate transporter 1/peptide transporter family substrate determinants.	based on recent in vitro data, a relatively large number of the plant nitrate transporter 1/peptide transporter family (npf) proteins have been suggested to function as gibberellic acid (ga) transporters. most ga transporting npf proteins also appear to transport other structurally unrelated phytohormones or metabolites. several of the gas used in previous in vitro assays are membrane permeable weak organic acids whose movement across membranes are influenced by the ph-sensitive ion-trap mechani ...	2019	31632416
kif2a scales meiotic spindle size in hymenochirus boettgeri.	size is a fundamental feature of biological systems that affects physiology at all levels. for example, the dynamic, microtubule-based spindle that mediates chromosome segregation scales to a wide range of cell sizes across different organisms and cell types. xenopus frog species possess a variety of egg and meiotic spindle sizes, and differences in activities or levels of microtubule-associated proteins in the egg cytoplasm between xenopus laevis and xenopus tropicalis have been shown to accoun ...	2019	31630945
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 of crucial residues in α-conotoxin ei inhibiting muscle nicotinic acetylcholine receptor.	α-conotoxins (α-ctxs) are small disulfide-rich peptides from venom of conus species that target nicotinic acetylcholine receptors (nachrs). the muscle-type nachrs have been recognized as a potential target for several diseases, such as myogenic disorders, muscle dystrophies, and myasthenia gravis. ei, an α4/7-ctx, mainly blocks α1β1δε nachrs and has an extra n-terminal extension of three amino acids. in this study, the alanine scanning (ala-scan) mutagenesis was applied in order to identify key ...	2019	31623211
popdc3 gene variants associate with a new form of limb girdle muscular dystrophy.	the popeye domain containing 3 (popdc3) gene encodes a membrane protein involved in cyclic adenosine monophosphate (camp) signaling. besides gastric cancer, no disease association has been described. we describe a new muscular dystrophy associated with this gene.	2019	31610034
embryogenesis of marsupial frogs (hemiphractidae), and the changes that accompany terrestrial development in frogs.	the developmental adaptations of the marsupial frogs gastrotheca riobambae and flectonotus pygmaeus (hemiphractidae) are described and compared with frogs belonging to seven additional families. incubation of embryos by the mother in marsupial frogs is associated with changes in the anatomy and physiology of the female, modifications of oogenesis, and extraordinary changes in embryonic development. the comparison of early development reveals that gene expression is highly conserved. however, the ...	2019	31598865
identification of lysine histidine transporter 2 as an 1-aminocyclopropane carboxylic acid transporter in arabidopsis thaliana by transgenic complementation approach.	1-aminocyclopropane-1-carboxylic acid (acc), a biosynthetic precursor of ethylene, has long been proposed to act as a mobile messenger in higher plants. however, little is known about the transport system of acc. recently, our genetic characterization of an acc-resistant mutant with normal ethylene sensitivity revealed that lysine histidine transporter 1 (lht1) functions as a transporter of acc. as amino acid transporters might have broad substrate specificity, we hypothesized that other amino a ...	2019	31572413
electrophysiological studies revealed cam1-mediated regulation of the arabidopsis calcium channel cngc12.	the arabidopsis cyclic nucleotide-gated channel (cngc) family consists of 20 members, which have been reported to participate in various physiological processes, such as pathogen defense, development, and thermotolerance. although cngc11 and cngc12 have been identified a decade ago and their role in programmed cell death is well studied, their precise channel regulation has not been studied electrophysiologically. here, we determined the channel activities of cngc11 and cngc12 utilizing the two- ...	2019	31572412
in vitro reconstruction of xenopus oocyte ovulation.	progesterone is widely used to induce maturation of isolated fully grown oocytes of the african clawed frog, xenopus laevis. however, the hormone fails to release oocytes from the layer of surrounding follicle cells. here, we report that maturation and follicle rupture can be recapitulated in vitro by treating isolated follicular oocytes with progesterone and low doses of the matrix metalloproteinase (mmp), collagenase, which are ineffective in the absence of the steroid. using this in vitro ovu ...	2019	31561408
bap1 regulates epigenetic switch from pluripotency to differentiation in developmental lineages giving rise to bap1-mutant cancers.	the bap1 tumor suppressor is mutated in many human cancers such as uveal melanoma, leading to poor patient outcome. it remains unclear how bap1 functions in normal biology or how its loss promotes cancer progression. here, we show that bap1 is critical for commitment to ectoderm, mesoderm, and neural crest lineages during xenopus laevis development. bap1 loss causes transcriptional silencing and failure of h3k27ac to accumulate at promoters of key genes regulating pluripotency-to-commitment tran ...	2019	31555735
structural determinants underlying permeant discrimination of the cx43 hemichannel.	connexin (cx) gap junction channels comprise two hemichannels in neighboring cells, and their permeability is well-described, but permeabilities of the single cx hemichannel remain largely unresolved. moreover, determination of isoform-specific cx hemichannel permeability is challenging because of concurrent expression of other channels with similar permeability profiles and inhibitor sensitivities. the mammalian cx hemichannels cx30 and cx43 are gated by extracellular divalent cations, removal ...	2019	31554662
emodepside has sex-dependent immobilizing effects on adult brugia malayi due to a differentially spliced binding pocket in the rck1 region of the slo-1 k channel.	filariae are parasitic nematodes that are transmitted to their definitive host as third-stage larvae by arthropod vectors like mosquitoes. filariae cause diseases including: lymphatic filariasis with distressing and disturbing symptoms like elephantiasis; and river blindness. filarial diseases affect millions of people in 73 countries throughout the topics and sub-tropics. the drugs available for mass drug administration, (ivermectin, albendazole and diethylcarbamazine), are ineffective against ...	2019	31553770
αd-conotoxins in species of the eastern pacific: the case of conus princeps from mexico.	conus snails produce venoms containing numerous peptides such as the α-conotoxins (α-ctxs), which are well-known nicotinic acetylcholine receptor (nachr) antagonists. thirty-eight chromatographic fractions from conus princeps venom extract were isolated by rp-hplc. the biological activities of 37 fractions (0.07 µg/µl) were assayed by two-electrode voltage clamp on human α7 nachrs expressed in xenopus laevis oocytes. fractions f7 and f16 notably inhibited the response elicited by acetylcholine b ...	2019	31336928
reference gene validation for quantitative real-time pcr studies in amphibian kidney-derived a6 epithelial cells.	quantitative real-time polymerase chain reaction is a widely used technique that relies on reference genes for the normalisation of gene expression. these reference genes are constitutively expressed and must remain stable across all samples and treatments. stability of housekeeping genes may vary and must be optimised for a specific tissue, sample or cell line. here we present a study screening for possible reference gene candidates, eef1a1, rpl8, sub1.l, clta, h4 and odc1, in the xenopus laevi ...	2019	31333044
involvement of g-quadruplex regions in mammalian replication origin activity.	genome-wide studies of dna replication origins revealed that origins preferentially associate with an origin g-rich repeated element (ogre), potentially forming g-quadruplexes (g4). here, we functionally address their requirements for dna replication initiation in a series of independent approaches. deletion of the ogre/g4 sequence strongly decreased the corresponding origin activity. conversely, the insertion of an ogre/g4 element created a new replication origin. this element also promoted rep ...	2019	31332171
na3 glycan: a potential therapy for retinal pigment epithelial deficiency.	atrophic age-related macular degeneration (amd) is the most common type of amd, yet there is no united states food and drug administration (fda)-approved therapy. this disease is characterized by retinal pigment epithelial (rpe) insufficiency, primarily in the macula, which affects the structure and physiology of photoreceptors and ultimately, visual function. in this study, we evaluated the protective effects of a naturally derived small molecule glycan therapeutic-asialo-, tri-antennary comple ...	2019	31322324
structure, development, and functional morphology of the cement gland of the giant danio, devario malabaricus.	aquatic species in several clades possess cement glands producing adhesive secretions of various strengths. in vertebrates, transient adhesive organs have been extensively studied in xenopus laevis, other anurans, and in several fish species. however, the development of these structures is not fully understood.	2019	31310039
evaluating the role of fish as surrogates for amphibians in pesticide ecological risk assessment.	ecological risk of chemicals to aquatic-phase amphibians has historically been evaluated by comparing estimated environmental concentrations in surface water to surrogate toxicity data from fish species. despite their obvious similarities, there are biological disparities among fish and amphibians that could affect their exposure and response to chemicals. given the alarming decline in amphibians, in which anthropogenic pollutants play at least some role, investigating the risk of chemicals to a ...	2019	31299708
the many faces of xenopus: xenopus laevis as a model system to study wolf-hirschhorn syndrome.	wolf-hirschhorn syndrome (whs) is a rare developmental disorder characterized by intellectual disability and various physical malformations including craniofacial, skeletal, and cardiac defects. these phenotypes, as they involve structures that are derived from the cranial neural crest, suggest that whs may be associated with abnormalities in neural crest cell (ncc) migration. this syndrome is linked with assorted mutations on the short arm of chromosome 4, most notably the microdeletion of a cr ...	2019	31297068
phosphomimetic substitution at ser-33 of the chloroquine resistance transporter pfcrt reconstitutes drug responses in plasmodium falciparum.	the chloroquine resistance transporter pfcrt of the human malaria parasite plasmodium falciparum confers resistance to the former first-line antimalarial drug chloroquine, and it modulates the responsiveness to a wide range of quinoline and quinoline-like compounds. pfcrt is post-translationally modified by phosphorylation, palmitoylation, and, possibly, ubiquitination. however, the impact of these post-translational modifications on p. falciparum biology and, in particular, the drug resistance- ...	2019	31285265
assessing predator-prey interactions in a chemically altered aquatic environment: the effects of ddt on xenopus laevis and culex sp. larvae interactions and behaviour.	behavioural assays are used as a tool to understand ecotoxicological effects on organisms, but are often not applied in an ecologically relevant context. assessment of the effect of chemical contaminants on behaviours relating to fitness and trophic interactions for example, requires incorporating predator-prey interactions to create impact assessments. dichlorodiphenyltrichloroethane (ddt) is a controlled substance but is still regularly used as a form of mosquito control. there is little expli ...	2019	31278447
effects of cis-bifenthrin enantiomers on the growth, behavioral, biomarkers of oxidative damage and bioaccumulation in xenopus laevis.	chirality should be taken into consideration when assessing the effect of synthetic pyrethroids to aquatic environmental safety. in our study, 96 h acute toxicity assay showed that enantiomers of cis-bf had an addictive effect of toxicity on xenopus laevis and r-cis-bifenthrin(r-cis-bf) had higher acute toxicity than s-cis-bf. in chronic assay, r-cis-bf exerted more toxic effect on behavior and development of tadpoles than s-cis-bf, and there was also enantioselective effect of cis-bf on antioxi ...	2019	31276910
neuroendocrine modulation of predator avoidance/prey capture tradeoffs: role of tectal npy2r receptors.	the optic tectum rapidly inhibits food intake when a visual threat is present. anatomical and electrophysiological evidence support a role for neuropeptide y (npy), originating from cells in the thalamus, in the tectal inhibition of prey capture. here we test the hypothesis that tectal npy receptor type 2 (npy2r) influences prey-capture and predator-avoidance responses in the african clawed frog, xenopus laevis. we tested two questions: 1) does tectal npy administration decrease food intake and ...	2019	31271760
impact of 4-aminopyridine on vestibulo-ocular reflex performance.	vestibulo-ocular reflexes (vor) are mediated by frequency-tuned pathways that separately transform the different dynamic and static aspects of head motion/position-related sensory signals into extraocular motor commands. voltage-dependent potassium conductances such as those formed by kv1.1 are important for the ability of vor circuit elements to encode highly transient motion components. here we describe the impact of the kv1.1 channel blocker 4-aminopyridine (4-ap) on spontaneous and motion-ev ...	2019	31270663
impacts of the synthetic androgen trenbolone on gonad differentiation and development - comparisons between three deeply diverged anuran families.	using a recently developed approach for testing endocrine disruptive chemicals (edcs) in amphibians, comprising synchronized tadpole exposure plus genetic and histological sexing of metamorphs in a flow-through-system, we tested the effects of 17β-trenbolone (tb), a widely used growth promoter in cattle farming, in three deeply diverged anuran families: the amphibian model species xenopus laevis (pipidae) and the non-models bufo(tes) viridis (bufonidae) and hyla arborea (hylidae). trenbolone was ...	2019	31270347
developmentally regulated gtp-binding protein 1 modulates ciliogenesis via an interaction with dishevelled.	cilia are critical for proper embryonic development and maintaining homeostasis. although extensively studied, there are still significant gaps regarding the proteins involved in regulating ciliogenesis. using the xenopus laevis embryo, we show that dishevelled (dvl), a key wnt signaling scaffold that is critical to proper ciliogenesis, interacts with drg1 (developmentally regulated gtp-binding protein 1). the loss of drg1 or disruption of the interaction with dvl reduces the length and number o ...	2019	31270137
phosphatidylinositol 4,5-bisphosphate (pip2) and ca2+ are both required to open the cl- channel tmem16a.	transmembrane member 16a (tmem16a) is a widely expressed ca2+-activated cl- channel with various physiological functions ranging from mucosal secretion to regulating smooth muscle contraction. understanding how tmem16a controls these physiological processes and how its dysregulation may cause disease requires a detailed understanding of how cellular processes and second messengers alter tmem16a channel gating. here we assessed the regulation of tmem16a gating by recording ca2+-evoked cl- current ...	2019	31266809
dyrk1a-related intellectual disability: a syndrome associated with congenital anomalies of the kidney and urinary tract.	haploinsufficiency of dyrk1a causes a recognizable clinical syndrome. the goal of this paper is to investigate congenital anomalies of the kidney and urinary tract (cakut) and genital defects (gd) in patients with dyrk1a variants.	2019	31263215
functional characterization of smn evolution in mouse models of sma.	spinal muscular atrophy (sma) is a monogenic neurodegenerative disorder and the leading genetic cause of infantile mortality. while several functions have been ascribed to the smn (survival motor neuron) protein, their specific contribution to the disease has yet to be fully elucidated. we hypothesized that some, but not all, smn homologues would rescue the sma phenotype in mouse models, thereby identifying disease-relevant domains. using aav9 to deliver smn homologs to sma mice, we identified a ...	2019	31263170
comparative analysis of p4ha1 and p4ha2 expression during xenopus laevis development.	collagen prolyl 4-hydroxylases (c-p4hs) are evolutionary conserved enzymes whose activity is essential for the correct folding of stable triple helical molecules of collagen and collagen-like proteins. they play crucial roles in embryo development, connective tissue functional organization, tumor growth and metastasis. despite the important function of these enzymes, little is known about their expression during vertebrate development. in this study, we determine and compare the previously undes ...	2019	31250915
transcriptome analysis of regeneration during xenopus laevis experimental twinning.	animal embryos have the remarkable property of self-organization. over 125 years ago, hans driesch separated the two blastomeres of sea urchin embryos and obtained twins, in what was the foundation of experimental embryology. since then, embryonic twinning has been obtained experimentally in many animals. in a recent study, we developed bisection methods that generate identical twins reliably from xenopus blastula embryos. in the present study, we have investigated the transcriptome of regenerat ...	2019	31250914
data demonstrating distinct embryonic developmental defects induced by bisphenol a alternatives.	embryos of xenopus laevis (african clawed frog) were exposed to the widespread environmental plasticizers bisphenol af (bpaf; 0.003-3 μm), bisphenol a (bpa; 1-50 μm), or 17β-estradiol (e2; 10 μm) from just after fertilization through 96 hours of development. the potencies and cellular and morphological effects were compared across chemical treatments and controls. the embryos were staged, counted and imaged, and time-lapse movies collected, on an inverted stereomicroscope and camera. the data sh ...	2019	31249853
an extracellular acidic cleft confers profound h+-sensitivity to epithelial sodium channels containing the δ-subunit in xenopus laevis.	the limited sodium availability of freshwater and terrestrial environments was a major physiological challenge during vertebrate evolution. the epithelial sodium channel (enac) is present in the apical membrane of sodium-absorbing vertebrate epithelia and evolved as part of a machinery for efficient sodium conservation. enac belongs to the degenerin/enac protein family and is the only member that opens without an external stimulus. we hypothesized that enac evolved from a proton-activated sodium ...	2019	31248986
commentary on classic paper "gimlich, r.l., gerhart, j.c., 1984. early cellular interactions promote embryonic axis formation in xenopus laevis. dev biol 104, 117-130."		2019	31235010
catalyst-free click pegylation reveals substantial mitochondrial atp synthase sub-unit alpha oxidation before and after fertilisation.	using non-reducing western blotting to assess protein thiol redox state is challenging because most reduced and oxidised forms migrate at the same molecular weight and are, therefore, indistinguishable. while copper catalysed click chemistry can be used to ligate a polyethylene glycol (peg) moiety termed click pegylation to mass shift the reduced or oxidised form as desired, the potential for copper catalysed auto-oxidation is problematic. here we define a catalyst-free trans-cyclooctene-methylt ...	2019	31234016
cardiotoxicity in african clawed frog (xenopus laevis) sub-chronically exposed to environmentally relevant atrazine concentrations: implications for species survival.	the toxic effects of different atrazine concentrations on tadpoles and adult male african clawed frogs (xenopus laevis) were assessed in a controlled laboratory environment following 90 days' exposure. the aim was to elucidate the danger of atrazine exposure on the cardiac tissue relative to its critical function of rhythmic contractility, fundamental for optimal blood circulation and homeostasis. tadpoles and adult frogs were exposed to 0 μg/l (control), 0.01 μg l-1, 200 μg l-1 and 500 μg l-1 c ...	2019	31203168
peia-5466: a novel peptide antagonist containing non-natural amino acids that selectively targets α3β2 nicotinic acetylcholine receptors.	pharmacologically distinguishing α3β2 nicotinic acetylcholine receptors (nachrs) from closely related subtypes, particularly α6β2, has been challenging due to the lack of subtype-selective ligands. we created analogs of α-conotoxin (α-ctx) peia to identify ligand-receptor interactions that could be exploited to selectively increase potency and selectivity for α3β2 nachrs. a series of peia analogs were synthesized by replacing amino acid residues in the second disulfide loop with standard or nons ...	2019	31194549
single cell proteomics by data-independent acquisition to study embryonic asymmetry in xenopus laevis.	techniques that allow single cell analysis are gaining widespread attention, and most of these studies utilize genomics-based approaches. while nanofluidic technologies have enabled mass spectrometric analysis of single cells, these measurements have been limited to metabolomics and lipidomic studies. single cell proteomics has the potential to improve our understanding of intercellular heterogeneity. however, this approach has faced challenges including limited sample availability, as well as a ...	2019	31194517
injection of mrna isolated from trophozoites of giardia intestinalis induces expression of three types of chloride currents in xenopus laevis oocytes.	giardia lamblia is one of the most important worldwide causes of intestinal infections, yet little is known about its cellular physiology, especially the diversity of ionic channels that this parasite expresses. in this work, we show that injection of mrna isolated from trophozoites of giardia, into xenopus laevis oocytes, induces expression of three types of chloride currents (here referred to as icl-g1, icl-g2, and icl-g3), which have different biophysical and pharmacological properties. icl-g ...	2019	31187589
the effect of xenopus laevis egg extracts with/without brg1 on the development of preimplantation cloned mouse embryos.	summarymuch effort has been devoted to improving the efficiency of animal cloning. the aim of this study was to investigate the effect of brg1 contained in xenopus egg extracts on the development of cloned mouse embryos. the results showed that mouse nih/3t3 cells were able to express pluripotent genes after treatment with egg extracts, indicating that the egg extracts contained reprogramming factors. after co-injection of xenopus egg extracts and single mouse cumulus cells into enucleated mouse ...	2019	31182178
dspe-peg modification of α-conotoxin txid.	in order to improve stability of a peptide marine drug lead, α-conotoxin txid, we synthesized and modified txid at the n-terminal with dspe-peg-nhs by a nucleophilic substitution reaction to prepare the dspe-peg-txid for the first time. the reaction conditions, including solvent, ratio, ph, and reaction time, were optimized systematically and the optimal one was reacted in dimethyl formamide at ph 8.2 with triethylamine at room temperature for 120 h. the in vitro stabilities in serum, simulated ...	2019	31181805
ecotoxicity of nanomaterials in amphibians: a critical review.	nanomaterials (nms) have been used in a growing number of commercial products, and their rapid expansion could lead to their release into the aquatic environments. however, there is limited knowledge about the impact of nms in the biota, especially the amphibians. the present study revised the historical use of amphibian species as a model system for nanoecotoxicological studies and summarized the data available in the scientific literature about the genotoxic, mutagenic, histopathological, embr ...	2019	31181520
disassembly of actin and keratin networks by aurora b kinase at the midplane of cleaving xenopus laevis eggs.	the large length scale of xenopus laevis eggs facilitates observation of bulk cytoplasm dynamics far from the cortex during cytokinesis. the first furrow ingresses through the egg midplane, which is demarcated by chromosomal passenger complex (cpc) localized on microtubule bundles at the boundary between asters. using an extract system, we found that local kinase activity of the aurora b kinase (aurkb) subunit of the cpc caused disassembly of f-actin and keratin between asters and local softenin ...	2019	31178324
organic anion-transporting polypeptide 1a4-mediated heterogeneous distribution of sulforhodamine-101 in rat hepatic lobules.	it has been known that organic anion-transporting polypeptides (oatps) involve hepatic transports several organic anionic compounds and drugs. this study aimed to investigate sulforhodamine-101 (sr-101) distribution in the rat liver, determine the molecules responsible for the distribution, and delineate the manner of distribution. after intravenous sr-101 administration, its distribution in frozen rat hepatic sections was examined. sr-101-derived signals were detected in regions around the hepa ...	2019	31174976
a sclerocornea-associated rad21 variant induces corneal stroma disorganization.	sclerocornea is a cornea opacification disorder. disorganized corneal stroma fibrils are observed in patients' cornea. previously we identified a rad21c1348t variant that is associated with a peripheral sclerocornea pedigree. to explore whether this rad21 variant can induce sclerocornea-related phenotype, and to investigate the possible mechanisms of such phenotype, the orthologous rad21 wild-type and variant mrnas were injected into xenopus laevis embryos and the developed eyes were subjected f ...	2019	31173765
ism1 regulates nodal signaling and asymmetric organ morphogenesis during development.	isthmin1 (ism1) was originally identified as a fibroblast group factor expressed in xenopus laevis embryonic brain, but its biological functions remain unclear. the spatiotemporal distribution of ism1, with high expression in the anterior primitive streak of the chick embryo and the anterior mesendoderm of the mouse embryo, suggested that ism1 may regulate signaling by the nodal subfamily of tgb-β cytokines that control embryo patterning. we report that ism1 is an inhibitor of nodal signaling. i ...	2019	31171630
mortality, teratogenicity and growth inhibition of three glyphosate formulations using frog embryo teratogenesis assay-xenopus.	ample evidence around the world exists suggesting a link between exposure to glyphosate, toxicity and perturbed physiological functions in non-target organisms. although glyphosate formulations are widely used for weed and alien plant management, their ecotoxicological information remain scanty. using the 96-hour frog embryo teratogenesis assay-xenopus protocol, embryotoxicity and teratogenicity of three glyphosate-based formulations were assessed. embryos of xenopus laevis were exposed to round ...	2019	31168868
impacts of the mhc class i-like xnc10 and innate-like t cells on tumor tolerance and rejection in the amphibian xenopus.	the conditions that lead to antitumor or protumor functions of natural killer t (nkt) cells against mammalian tumors are only partially understood. therefore, insights into the evolutionary conservation of nkt and their analogs-innate-like t (it) cells-may reveal factors that contribute to tumor eradication. as such, we investigated the amphibian xenopus laevis it cells and interacting mhc class i-like (xnc or mhc1b.l) genes against ff-2 thymic lymphoid tumors. upon ff-2 intraperitoneal transpla ...	2019	31155639
the direct permeation of nanoparticles through the plasma membrane transiently modifies its properties.	the exposure to metal nanoparticles (nps) has increased with their widespread use in industry, research and medicine. it is well known that nps may enter cells and that this mechanism is crucial to exert both the therapeutic and toxicity effects. the main cellular entrance route is endocytosis-based, however, recent experimental studies, have reported that nps can also enter the cell crossing directly the plasma membrane, it is thus important to investigate this alternative internalization mecha ...	2019	31150635
the plus maze and scototaxis test are not valid behavioral assays for anxiety assessment in the south african clawed frog.	there are no behavioral models for testing anxiety in amphibians, a group of animals widely used for developmental, ecotoxicological, and genetic research. we aimed to validate two common rodent paradigms, the plus maze and the scototaxis test, for use in the aquatic african clawed frog (xenopus laevis). we predicted: (a) that frogs would prefer the dark, vs. light, portions of the testing arenas (face validity), (b) that this behavior could be altered with acute administration of anxio-selectiv ...	2019	31144017
acclimation temperature effects on locomotor traits in adult aquatic anurans (x. tropicalis and x. laevis) from different latitudes: possible implications for climate change.	climate change is in part responsible for the 70% decline in amphibian species numbers worldwide. although temperature is expected to impact whole-organism performance in ectotherms, reversible thermal acclimation has been suggested as a mechanism that may buffer responses to abrupt temperature changes. here, we test for an effect of acclimation on locomotor performance traits (jump force and stamina) in adults of two predominantly aquatic and closely related frog species from different climatic ...	2019	31139411
using the xenopus developmental eye regrowth system to distinguish the role of developmental versus regenerative mechanisms.	a longstanding challenge in regeneration biology is to understand the role of developmental mechanisms in restoring lost or damaged tissues and organs. as these body structures were built during embryogenesis, it is not surprising that a number of developmental mechanisms are also active during regeneration. however, it remains unclear whether developmental mechanisms act similarly or differently during regeneration as compared to development. since regeneration is studied in the context of matu ...	2019	31139088
preserving genome integrity during the early embryonic dna replication cycles.	during the very early stages of embryonic development chromosome replication occurs under rather challenging conditions, including a very short cell cycle, absence of transcription, a relaxed dna damage response and, in certain animal species, a highly contracted s-phase. this raises the puzzling question of how the genome can be faithfully replicated in such a peculiar metabolic context. recent studies have provided new insights into this issue, and unveiled that embryos are prone to accumulate ...	2019	31137726
growth at cold temperature increases the number of motor neurons to optimize locomotor function.	during vertebrate development, spinal neurons differentiate and connect to generate a system that performs sensorimotor functions critical for survival. spontaneous ca2+ activity regulates different aspects of spinal neuron differentiation. it is unclear whether environmental factors can modulate this ca2+ activity in developing spinal neurons to alter their specialization and ultimately adjust sensorimotor behavior to fit the environment. here, we show that growing xenopus laevis embryos at col ...	2019	31130453
genome wide decrease of dna replication eye density at the midblastula transition of xenopus laevis.	during the first rapid divisions of early development in many species, the dna:cytoplasm ratio increases until the midblastula transition (mbt) when transcription resumes and cell cycles lengthen. s phase is very rapid in early embryos, about 20-30 times faster than in differentiated cells. using a combination of dna fiber studies and a xenopus laevis embryonic in vitro replication system, we show that s phase slows down shortly after the mbt owing to a genome wide decrease of replication eye de ...	2019	31130065
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
nucleotide receptor p2ry4 is required for head formation via induction and maintenance of head organizer in xenopus laevis.	vertebrates have unique head structures that are mainly composed of the central nervous system, the neural crest, and placode cells. these head structures are brought about initially by the neural induction between the organizer and the prospective neuroectoderm at early gastrula stage. purinergic receptors are activated by nucleotides released from cells and influence intracellular signaling pathways, such as phospholipase c and adenylate cyclase signaling pathways. as p2y receptor is vertebrat ...	2019	30069871
design, synthesis, and pharmacological evaluation of novel β2/3 subunit-selective γ-aminobutyric acid type a (gabaa) receptor modulators.	subunit-selective modulation of γ-aminobutyric acid type a receptors (gabaar) is considered to exert fewer side effects compared to unselective clinically used drugs. here, the β2/3 subunit-selective gabaar modulators valerenic acid (va) and loreclezole (lor) guided the synthesis of novel subunit-selective ligands with simplified structures. we studied their effects on gabaars expressed in xenopus laevis oocytes using two-microelectrode voltage clamp technique. five compounds showed significantl ...	2019	30289721
comparisons of socs mrna and protein levels in xenopus provide insights into optic nerve regenerative success.	in vertebrates from fishes to mammals, optic nerve injury induces increased expression ofsuppressor of cytokine signaling 3(socs3) mrna, a modulator of cytokine signaling that is known to inhibit cns axon regeneration. unlike amniotes, however, anamniotes successfully regenerate optic axons, despite this increase. to address this seeming paradox, we examined the socs3 response to optic nerve injury in the frog,xenopus laevis, at both the mrna and protein levels. far from being only transiently i ...	2019	30315759
lymphocyte deficiency induced by sublethal irradiation in xenopus.	in many studies of diseases affecting amphibians, it is important to determine to what extent lymphocyte-mediated defenses are involved. for example, in studies of the nature of the immune response of xenopus laevis to the amphibian chytrid fungus, batrachochytrium dendrobatidis, it was essential to determine if mucosal antimicrobial peptides or lymphocyte-mediated immunity was most important for resistance to this skin pathogen. in this protocol, we describe a method for sublethal irradiation t ...	2019	30104411
mass spectrometry-based absolute quantification of single xenopus embryo proteomes.	early xenopus development is characterized by a poor correlation between global mrna and protein abundances due to maternal mrna and protein loading. therefore, proteome profiling is necessary to study gene expression dynamics during early xenopus development. in contrast to mammals, single xenopus eggs and embryos contain enough protein to allow identification and quantification of thousands of proteins using mass spectrometry-based proteomics. in addition to investigating developmental process ...	2019	30104410
regulation of melanopsin signaling: key interactions of the nonvisual photopigment.	melanopsin is a g protein-coupled receptor with a peak sensitivity in the blue part of the spectrum, which plays a key role in nonvisual light-mediated signaling. recently, its importance in forming visual pathway as well as its role in blood vessels photorelaxation was also revealed. melanopsin was discovered in 1998 in xenopus leavis. since then, the melanopsin presence was demonstrated across the species. the existence of two melanopsin genes (opn4m and opn4x) as well as melanopsin isoforms r ...	2019	30102761
expression cloning human and rat renal cortex na/pi cotransporters: behind the scenes in the murer laboratory.	in the pre-genomic era, the cloning of a cdna represented a significant achievement, particularly if the gene of interest encoded a membrane protein. at the time, molecular probes such as partial peptide sequences, suitable nucleic acid sequences, or antibodies were unavailable for most proteins and the "sodium-phosphate transporter" was no exception. in contrast, brush-border membrane vesicles and epithelial cell culture experiments had established a reliable set of functional hallmarks that de ...	2019	30175377
high-affinity k+ transporters from a halophyte, sporobolus virginicus, mediate both k+ and na+ transport in transgenic arabidopsis, x. laevis oocytes and yeast.	class ii high-affinity potassium transporters (hkts) have been proposed to mediate na+-k+ co-transport in plants, as well as na+ and k+ homeostasis under k+-starved and saline environments. we identified class ii hkts, namely svhkt2;1 and svhkt2;2 (svhkts), from the halophytic turf grass, sporobolus virginicus. svhkt2;2 expression in s. virginicus was up-regulated by nacl treatment, while svhkt2;1 expression was assumed to be up-regulated by k+ starvation and down-regulated by nacl treatment. lo ...	2019	30325438
generation and analysis of xenopus laevis models of retinal degeneration using crispr/cas9.	xenopus laevis have proven to be a useful system for rapid generation and analysis of transgenic models of human retinal disease. however, experimental approaches in this system were limited by lack of a robust knockdown or knockout technology. here we describe a protocol for generation of cas9-edited x. laevis embryos. the technique introduces point mutations into the genome of x. laevis resulting in in-frame and out-of-frame insertions and deletions that allow modeling of both dominant and rec ...	2019	30324446
a modified tripeptide motif of rs1 (rsc1a1) down-regulates exocytotic pathways of human na+-d-glucose cotransporters sglt1, sglt2, and glucose sensor sglt3 in the presence of glucose.	a domain of protein rs1 (rsc1a1) called rs1-reg down-regulates the plasma membrane abundance of na+-d-glucose cotransporter sglt1 by blocking the exocytotic pathway at the trans-golgi. this effect is blunted by intracellular glucose but prevails when serine in a qsp (gln-ser-pro) motif is replaced by glutamate [rs1-reg(s20e)]. rs1-reg binds to ornithine decarboxylase (odc) and inhibits odc in a glucose-dependent manner. because the odc inhibitor difluoromethylornithine (dfmo) acts like rs1-reg(s ...	2019	30355744
functional studies of transcriptional cofactors via microinjection-mediated gene editing in xenopus.	the anuran xenopus laevis has been studied for decades as a model for vertebrate cell and developmental biology. more recently, the highly related species xenopus tropicalis has offered the opportunity to carry out genetic studies due to its diploid genome as compared to the pseudo-tetraploid xenopus laevis. amphibians undergo a biphasic development: embryogenesis to produce a free-living tadpoles and subsequent metamorphosis to transform the tadpole to a frog. this second phase mimics the so-ca ...	2019	30353533