Publications

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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
evaluating potential distribution of high-risk aquatic invasive species in the water garden and aquarium trade at a global scale based on current established populations.	aquatic non-native invasive species are commonly traded in the worldwide water garden and aquarium markets, and some of these species pose major threats to the economy, the environment, and human health. understanding the potential suitable habitat for these species at a global scale and at regional scales can inform risk assessments and predict future potential establishment. typically, global habitat suitability models are fit for freshwater species with only climate variables, which provides ...	2019	30428498
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
spindle assembly in egg extracts of the marsabit clawed frog, xenopus borealis.	egg extracts of the african clawed frog xenopus laevis have provided a cell-free system instrumental in elucidating events of the cell cycle, including mechanisms of spindle assembly. comparison with extracts from the diploid western clawed frog, xenopus tropicalis, which is smaller at the organism, cellular and subcellular levels, has enabled the identification of spindle size scaling factors. we set out to characterize the marsabit clawed frog, xenopus borealis, which is intermediate in size b ...	2018	29573195
cell cycles during early steps of amphibian embryogenesis: a review.	the published data on cell cycles during the initial (pregastrular) period of embryonic development in representatives of the class amphibia have been critically discussed. we have also used the literature data on ontogenetic diversity of these animals. the relatively small eggs of two principal model species for amphibian embryology, the mexican axolotl and the african clawed frog, undergo the extensive series of rapid synchronous cleavage divisions, after which the midblastula transition (mbt) ...	2018	30240720
the tmem16a channel mediates the fast polyspermy block in xenopus laevis.	in externally fertilizing animals, such as sea urchins and frogs, prolonged depolarization of the egg immediately after fertilization inhibits the entry of additional sperm-a phenomenon known as the fast block to polyspermy. in the african clawed frog xenopus laevis, this depolarization is driven by ca2+-activated cl- efflux. although the prominent ca2+-activated cl- currents generated in immature x. laevis oocytes are mediated by x. laevis transmembrane protein 16a (xtmem16a) channels, little i ...	2018	30012842
skin regeneration of amphibians: a novel model for skin regeneration as adults.	adult mammals do not regenerate the dermis of the skin but form a scar after a deep skin injury. since a scar causes serious medical problems, skin regeneration, instead of formation of a scar, has been strongly desired from a clinical point of view. recent studies have suggested multiple origins of myofibroblasts, which are scar-forming cells in skin wound healing of mammals. while amphibians have skin structures that are basically common to mammals as tetrapods, both urodele and anuran amphibi ...	2018	29947057