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oxidized glutathione increases delta-subunit expressing epithelial sodium channel activity in xenopus laevis oocytes.epithelial sodium channels (enac) are heterotrimeric structures, made up of α, β, and γ subunits, and play an important role in maintaining fluid homeostasis. when δ-enac subunits are expressed in place of (or in addition to) the α-enac subunit alongside β- and γ- subunits, fundamental changes in the biophysical properties of enac can be observed. using human enac crna constructs and the xenopas laevis oocyte expression system, we show that oxidized glutathione (gssg) differently effects αβγ-ena ...202032656545
mambalgin-2 induces cell cycle arrest and apoptosis in glioma cells via interaction with asic1a.gliomas are fast growing and highly invasive brain tumors, characterized by tumor microenvironment acidification that drives glioma cell growth and migration. channels containing acid-sensing ion channel 1a subunit (asic1a) mediate amiloride-sensitive cation influx in late stage glioma cells, but not in normal astrocytes. thus, selective targeting of asic1a can be a perspective strategy for glioma treatment. here, asic1a expression in u251 mg and a172 glioma cells, but not in normal astrocytes, ...202032650495
transcriptomic analysis identifies early cellular and molecular events by which estrogen disrupts testis differentiation and causes feminization in xenopus laevis.extensive studies have shown that estrogenic endocrine-disrupting chemicals (edcs) can disrupt testis differentiation and even cause feminization in vertebrates. however, little is known about the mechanisms by which estrogenic edcs disrupt testis differentiation. here, we employed xenopus laevis, a model amphibian species sensitive to estrogenic edcs, to explore the molecular and cellular events by which 17β-estradiol (e2) disrupts testis differentiation and causes feminization. following water ...202032645606
altered glutaminase 1 activity during neurulation and its potential implications in neural tube defects.the neurulation process is regulated by a large amount of genetic and environmental factors that determine the establishment, folding, and fusion of the neural plate to form the neural tube, which develops into the main structure of the central nervous system. a recently described factor involved in this process is glutamate. through nmda ionotropic receptor, glutamate modifies intracellular ca2+ dynamics allowing the oriented cell migration and proliferation, essentials processes in neurulation ...202032636743
the histone h3-h4 tetramer is a copper reductase enzyme.eukaryotic histone h3-h4 tetramers contain a putative copper (cu2+) binding site at the h3-h3' dimerization interface with unknown function. the coincident emergence of eukaryotes with global oxygenation, which challenged cellular copper utilization, raised the possibility that histones may function in cellular copper homeostasis. we report that the recombinant xenopus laevis h3-h4 tetramer is an oxidoreductase enzyme that binds cu2+ and catalyzes its reduction to cu1+ in vitro. loss- and gain-o ...202032631887
heterologous expression of concatenated nicotinic ach receptors: pros and cons of subunit concatenation and recommendations for construct designs.concatenation of cys-loop receptor subunits is a commonly used technique to ensure experimental control of receptor assembly. however, we recently demonstrated that widely used constructs did not lead to the expression of uniform pools of ternary and more complex receptors. the aim was therefore to identify viable strategies for designing concatenated constructs that would allow strict control of resultant receptor pools.202032627170
relationship between oxygen consumption and neuronal activity in a defined neural circuit.neuronal computations related to sensory and motor activity along with the maintenance of spike discharge, synaptic transmission, and associated housekeeping are energetically demanding. the most efficient metabolic process to provide large amounts of energy equivalents is oxidative phosphorylation and thus dependent on o2 consumption. therefore, o2 levels in the brain are a critical parameter that influences neuronal function. measurements of o2 consumption have been used to estimate the cost o ...202032615976
comprehensive imaging of sensory-evoked activity of entire neurons within the awake developing brain using ultrafast aod-based random-access two-photon microscopy.determining how neurons transform synaptic input and encode information in action potential (ap) firing output is required for understanding dendritic integration, neural transforms and encoding. limitations in the speed of imaging 3d volumes of brain encompassing complex dendritic arbors in vivo using conventional galvanometer mirror-based laser-scanning microscopy has hampered fully capturing fluorescent sensors of activity throughout an individual neuron's entire complement of synaptic inputs ...202032612514
cofactor-enabled functional expression of fruit fly, honeybee, and bumblebee nicotinic receptors reveals picomolar neonicotinoid actions.the difficulty of achieving robust functional expression of insect nicotinic acetylcholine receptors (nachrs) has hampered our understanding of these important molecular targets of globally deployed neonicotinoid insecticides at a time when concerns have grown regarding the toxicity of this chemotype to insect pollinators. we show that thioredoxin-related transmembrane protein 3 (tmx3) is essential to enable robust expression in xenopus laevis oocytes of honeybee (apis mellifera) and bumblebee ( ...202032611810
disabled-2: a positive regulator of the early differentiation of myoblasts.dab2 is an adaptor protein and a tumor suppressor. our previous study has found that dab2 was expressed in early differentiating skeletal muscles in mouse embryos. in this study, we determined the role of dab2 in the skeletal muscle differentiation using c2c12 myoblasts in vitro and xenopus laevis embryos in vivo. the expression of dab2 was increased in c2c12 myoblasts during the formation of myotubes in vitro. knockdown of dab2 expression in c2c12 myoblasts resulted in a reduction of myotube fo ...202032607799
comparing the effect of triadimefon and its metabolite on male and female xenopus laevis: obstructed growth and gonad morphology.amphibians are the most endangered class of vertebrates. in this study, xenopus laevis frogs were exposed to 0, 1 and 10 mg/l of triadimefon or triadimenol. after 14 or 28 days of exposure, high levels of triadimefon or triadimenol obstructed the growth of frogs. however, low levels of triadimefon induced the growth of females after the longer period of exposure. we also found that the antioxidant enzyme activity and ldh levels in males were higher than those in females after 28-days exposure. i ...202032603964
the histone chaperone fact induces cas9 multi-turnover behavior and modifies genome manipulation in human cells.cas9 is a prokaryotic rna-guided dna endonuclease that binds substrates tightly in vitro but turns over rapidly when used to manipulate genomes in eukaryotic cells. little is known about the factors responsible for dislodging cas9 or how they influence genome engineering. unbiased detection through proximity labeling of transient protein interactions in cell-free xenopus laevis egg extract identified the dimeric histone chaperone facilitates chromatin transcription (fact) as an interactor of sub ...202032603710
active forces shape the metaphase spindle through a mechanical instability.the metaphase spindle is a dynamic structure orchestrating chromosome segregation during cell division. recently, soft matter approaches have shown that the spindle behaves as an active liquid crystal. still, it remains unclear how active force generation contributes to its characteristic spindle-like shape. here we combine theory and experiments to show that molecular motor-driven forces shape the structure through a barreling-type instability. we test our physical model by titrating dynein act ...202032601228
a turripeptide from polystira nobilis venom inhibits human α3β2 and α7 nicotinic acetylcholine receptors.almost all marine snails within superfamily conoidea produce venoms containing numerous neuroactive peptides. most toxins characterized from members of this superfamily are produced by species belonging to family conidae. these toxins (conotoxins) affect diverse membrane proteins, such as voltage- and ligand-gated ion channels, including nicotinic acetylcholine receptors (nachrs). family turridae has been considerably less studied than their conidae counterpart and, therefore, turrid toxins (tur ...202032592834
organizing the oocyte: rna localization meets phase separation.rna localization is a key biological strategy for organizing the cytoplasm and generating both cellular and developmental polarity. during rna localization, rnas are targeted asymmetrically to specific subcellular destinations, resulting in spatially and temporally restricted gene expression through local protein synthesis. first discovered in oocytes and embryos, rna localization is now recognized as a significant regulatory strategy for diverse rnas, both coding and non-coding, in a wide range ...202032591084
contribution of monocarboxylate transporter 6 to the pharmacokinetics and pharmacodynamics of bumetanide in mice.bumetanide, a sulfamyl loop diuretic, is used for the treatment of edema in association with congestive heart failure. being a polar, anionic compound at physiologic ph, bumetanide uptake and efflux into different tissues is largely transporter-mediated. of note, organic anion transporters (slc22a) have been extensively studied in terms of their importance in transporting bumetanide to its primary site of action in the kidney. the contribution of one of the less-studied bumetanide transporters, ...202032587098
functional analysis of the osnpf4.5 nitrate transporter reveals a conserved mycorrhizal pathway of nitrogen acquisition in plants.low availability of nitrogen (n) is often a major limiting factor to crop yield in most nutrient-poor soils. arbuscular mycorrhizal (am) fungi are beneficial symbionts of most land plants that enhance plant nutrient uptake, particularly of phosphate. a growing number of reports point to the substantially increased n accumulation in many mycorrhizal plants; however, the contribution of am symbiosis to plant n nutrition and the mechanisms underlying the am-mediated n acquisition are still in the e ...202032586957
acute toxicity of fluazinam to aquatic organisms and its bioaccumulation in brachydanio rerio.fluazinam (fzn) is a dinitroaniline fungicide. to evaluate the environmental risk of fzn in aquatic environments and ascertain the potential danger to typical aquatic organisms in china, the acute toxicity of fzn to representative aquatic organisms, including brachydanio rerio, chlorella vulgaris beij., daphnia magna straus, and xenopus laevis, was measured, and its bioaccumulation properties in brachydanio rerio were further investigated. the results showed that the acute toxicity of fzn to bra ...202032583109
electromechanical coupling of the kv1.1 voltage-gated k+ channel is fine-tuned by the simplest amino acid residue in the s4-s5 linker.investigating the shaker-related k+ channel kv1.1, the dysfunction of which is responsible for episodic ataxia 1 (ea1), at the functional and molecular level provides valuable understandings on normal channel dynamics, structural correlates underlying voltage-gating, and disease-causing mechanisms. most studies focused on apparently functional amino acid residues composing voltage-gated k+ channels, neglecting the simplest ones. glycine at position 311 of kv1.1 is highly conserved both evolution ...202032577860
polo-like kinase 1 (plk1) is a positive regulator of dna replication in the xenopus in vitro system.polo-like kinase 1 (plk1) is a cell cycle kinase essential for mitosis progression, but also important for checkpoint recovery and adaptation in response to dna damage and replication stress. however, although plk1 is expressed in s phase, little is known about its function during unperturbed dna replication. using xenopus laevis egg extracts, mimicking early embryonic replication, we demonstrate that plk1 is simultaneously recruited to chromatin with pre-replication proteins where it accumulate ...202032573322
molecular regulation of α3β4 nicotinic acetylcholine receptors by lupeol in cardiovascular system.cardiovascular disease (cvd) occurs globally and has a high mortality rate. the highest risk factor for developing cvd is high blood pressure. currently, natural products are emerging for the treatment of hypertension to avoid the side effects of drugs. among existing natural products, lupeol is known to be effective against hypertension in animal experiments. however, there exists no study regarding the molecular physiological evidence against the effects of lupeol. consequently, we investigate ...202032570692
three host plant volatiles, hexanal, lauric acid, and tetradecane, are detected by an antenna-biased expressed odorant receptor 27 in the dark black chafer holotrichia parallela.insects rely on olfaction to locate their host plants by antennae in complex chemical environments. odorant receptor (or) genes are thought to play a crucial role in the process. ors function together with odorant coreceptors to determine the specificity and sensitivity of olfactory reception. the dark black chafer, holotrichia parallela motschulsky (coleoptera: scarabaeidae), is a destructive underground pest. to understand the molecular basis of h. parallela olfactory reception, an olfactory-b ...202032551589
periodic albinism of a widely used albino mutant of xenopus laevis caused by deletion of two exons in the hermansky-pudlak syndrome type 4 gene.the periodic albino mutant of xenopus laevis is a recessive mutant, in which reduced amounts of melanin appear in the retinal pigment epithelium (rpe) and in melanophores at the late embryonic stage, after which both rpe and melanophores gradually depigment. three types of pigment cells (melanophores, iridophores, and xanthophores) have been reported to be affected in this albino. however, the causative gene of the periodic albinism remains unknown. hermansky-pudlak syndrome (hps) is an autosoma ...202033147376
disease-associated hcn4 v759i variant is not sufficient to impair cardiac pacemaking.the hyperpolarization-activated cation current if is a key determinant for cardiac pacemaker activity. it is conducted by subunits of the hyperpolarization-activated cyclic nucleotide-gated (hcn) channel family, of which hcn4 is predominant in mammalian heart. both loss-of-function and gain-of-function mutations of the hcn4 gene are associated with sinus node dysfunction in humans; however, their functional impact is not fully understood yet. here, we sought to characterize a hcn4 v759i variant ...202033095298
using an aquatic model, xenopus laevis, to uncover the role of chromodomain 1 in craniofacial disorders.the chromodomain family member chromodomain 1 (chd1) has been shown to have numerous critical molecular functions including transcriptional regulation, splicing, and dna repair. complete loss of function of this gene is not compatible with life. on the other hand, missense and copy number variants of chd1 can result in intellectual disabilities and craniofacial malformations in human patients including cleft palate and pilarowski-bjornsson syndrome. we have used the aquatic developmental model o ...202032918369
acute consequences of a unilateral viiith nerve transection on vestibulo-ocular and optokinetic reflexes in xenopus laevis tadpoles.loss of peripheral vestibular function provokes severe impairments of gaze and posture stabilization in humans and animals. however, relatively little is known about the extent of the instantaneous deficits. this is mostly due to the fact that in humans a spontaneous loss often goes unnoticed initially and targeted lesions in animals are performed under deep anesthesia, which prevents immediate evaluation of behavioral deficits. here, we use isolated preparations of xenopus laevis tadpoles with ...202032915311
l-glutamic acid monosodium salt reduces the harmful effect of lithium on the development of xenopus laevis embryos.many xenobiotics in the environment affect the human body in various ways. among those xenobiotics, lithium chloride (li, licl) and monosodium glutamate (l-glutamic acid monosodium salt, msg) compounds affect the crucial processes of stem cell differentiation, cell proliferation, developmental gene expression, and overall development in animals. in this study, we aimed to examine the developmental effects of exposure to flavor enhancer msg and lici medicament on xenopus embryos using the frog em ...202032705564
uncoupling sodium channel dimers restores the phenotype of a pain-linked nav 1.7 channel mutation.the voltage-gated sodium channel nav 1.7 is essential for adequate perception of painful stimuli. mutations in the encoding gene, scn9a, cause various pain syndromes in humans. the hnav 1.7/a1632e channel mutant causes symptoms of erythromelalgia and paroxysmal extreme pain disorder (pepd), and its main gating change is a strongly enhanced persistent current. on the basis of recently published 3d structures of voltage-gated sodium channels, we investigated how the inactivation particle binds to ...202032663327
trpm6 and trpm7: novel players in cell intercalation during vertebrate embryonic development.a common theme in organogenesis is how the final structure of organs emerge from epithelial tube structures, with the formation of the neural tube being one of the best examples. two types of cell movements co-occur during neural tube closure involving the migration of cells toward the midline of the embryo (mediolateral intercalation or convergent extension) as well as the deep movement of cells from inside the embryo to the outside of the lateral side of the neural plate (radial intercalation) ...202032315468
effects of bisphenol a and its alternative bisphenol f on notch signaling and intestinal development: a novel signaling by which bisphenols disrupt vertebrate development.we previously found bisphenol a (bpa) alternative, bisphenol f (bpf) upregulated notch-related gene expression in intestines of the african clawed frog xenopus laevis, suggesting an agonistic action on notch signaling, a crucial signaling in multiple biological processes during development. here, we aimed to confirm the actions of bpa and bpf on notch signaling and to reveal their effects on intestinal development. using x. laevis, an excellent model for developmental biology, we found that 10-1 ...202032311622
modeling bainbridge-ropers syndrome in xenopus laevis embryos.the additional sex combs-like (asxl1-3) genes are linked to human neurodevelopmental disorders. the de novo truncating variants in asxl1-3 proteins serve as the genetic basis for severe neurodevelopmental diseases such as bohring-opitz, shashi-pena, and bainbridge-ropers syndromes, respectively. the phenotypes of these syndromes are similar but not identical, and include dramatic craniofacial defects, microcephaly, developmental delay, and severe intellectual disability, with a loss of speech an ...202032132929
hplc reveals novel features of nucleoside and nucleobase homeostasis, nucleoside metabolism and nucleoside transport.humans possess three members of the cation-coupled concentrative nucleoside transporter cnt (slc 28) family, hcnt1-3: hcnt1 is selective for pyrimidine nucleosides but also transports adenosine, hcnt2 transports purine nucleosides and uridine, and hcnt3 transports both pyrimidine and purine nucleosides. hcnt1/2 transport nucleosides using the transmembrane na+ electrochemical gradient, while hcnt3 is both na+- and h+-coupled. by producing recombinant hcnt3 in xenopus laevis oocytes, we have used ...202032126230
evaluation of the effects of low concentrations of bisphenol af on gonadal development using the xenopus laevis model: a finding of testicular differentiation inhibition coupled with feminization.developmental exposures to estrogenic chemicals possibly cause structural and functional abnormalities of reproductive organs in vertebrates. bisphenol af (bpaf), a bisphenol a (bpa) analogue, has been shown to have higher estrogenic activity than bpa, but little is known about the effects of bpaf on gonadal development, particularly gonadal differentiation. we aimed to determine whether low concentrations of bpaf could disrupt gonadal differentiation and subsequent development using xenopus lae ...202031991354
cfap43 modulates ciliary beating in mouse and xenopus.malfunctions of motile cilia cause a variety of developmental defects and diseases in humans and animal model organisms. defects include impaired mucociliary clearance of the airways, sperm immotility, hydrocephalus and organ laterality. here, we characterize the evolutionary conserved cfap43 gene by loss-of-function experiments in the mouse and the frog xenopus laevis. cfap43 is expressed in tissues carrying motile cilia and acts as a target gene of the transcription factor foxj1, which is esse ...202031884020
insights regarding skin regeneration in non-amniote vertebrates: skin regeneration without scar formation and potential step-up to a higher level of regeneration.skin wounds are among the most common injuries in animals and humans. vertebrate skin is composed of an epidermis and dermis. after a deep skin injury in mammals, the wound heals, but the dermis cannot regenerate. instead, collagenous scar tissue forms to fill the gap in the dermis, but the scar does not function like the dermis and often causes disfiguration. in contrast, in non-amniote vertebrates, including fish and amphibians, the dermis and skin derivatives are regenerated after a deep skin ...202031831357
impact of copper in xenopus laevis liver: histological damages and atp7b downregulation.copper is an essential micronutrient but its excess in the dietary can be toxic. both copper deficiency and abundance can occur in natural conditions and can lead to pathological dysfunctions. many of the toxic effects of copper, such as increased lipid peroxidation in cell membranes and dna damage, are due to its role in the generation of oxygen free radicals. copper is released into the environment by both natural sources and human activities and it can damage organisms and ecosystems. in the ...202031757510
modulation by neonicotinoids of honeybee α1/chicken β2 hybrid nicotinic acetylcholine receptors expressed in xenopus laevis oocytes.neonicotinoids targeting insect nicotinic acetylcholine (ach) receptors (insect nachrs) are used for crop protection, but there is a concern about adverse effects on pollinators such as honeybees (apis mellifera). thus, we investigated the agonist actions of neonicotinoids (imidacloprid, thiacloprid and clothianidin) on a. mellifera α1 (amα1)/chicken β2 hybrid nachrs in xenopus laevis oocytes according to the subunit stoichiometry of (amα1)3(β2)2 and (amα1)2(β2)3 using voltage-clamp electrophysi ...202032448414
the mechanism of loop c-neonicotinoid interactions at insect nicotinic acetylcholine receptor α1 subunit predicts resistance emergence in pests.neonicotinoids selectively modulate insect nicotinic acetylcholine receptors (insect nachrs). studies have shown that serine with ability to form a hydrogen bond in loop c of some insect nachr α subunits and glutamate with a negative charge at the corresponding position in vertebrate nachrs may contribute to enhancing and reducing the neonicotinoid actions, respectively. however, there is no clear evidence what loop c properties underpin the target site actions of neonicotinoids. thus, we have i ...202032371996
effects of copper on the neuromasts of xenopus laevis.fish and aquatic amphibians possess neuromasts on the surface of their body that constitute the lateral line, a sensory system used to detect water displacement. copper is known to inactivate the neuromast organs of this system. copper-induced neuromast loss in african clawed frogs, xenopus laevis, was examined by exposing nieuwkoop-faber stage 54-55 larvae to copper concentrations of 0, 100, 200, 300, and 400 µg/l for 96 h, followed by an examination of neuromast counts, staining intensity, and ...202033180147
ecotoxicological assessment of commercial boron nitride nanotubes toward xenopus laevis tadpoles and host-associated gut microbiota.despite the growing interest for boron nitride nanotubes (bnnt) due to their unique properties, data on the evaluation of the environmental risk potential of this emerging engineered nanomaterial are currently lacking. therefore, the ecotoxicity of a commercial form of bnnt (containing tubes, hexagonal-boron nitride, and boron) was assessed in vivo toward larvae of the amphibian xenopus laevis. following the exposure, multiple endpoints were measured in the tadpoles as well as in bacterial commu ...202033171057
mechanisms activating latent functions of pip aquaporin water channels via the interaction between pip1 and pip2 proteins.plant plasma-membrane type pip aquaporins are classified into two groups, pip1s and pip2s. in this study, we focused on hvpip1; 2, a pip1 in barley (hordeum vulgare), to dissect the molecular mechanisms that evoke hvpip1-mediated water transport. no hvpip1; 2 protein was localized to the plasma membrane when expressed alone in xenopus laevis oocytes. in contrast, a chimeric hvpip1; 2 protein (hvpip1; 2_24nc), in which the n- and c-terminal regions were replaced with the corresponding regions fro ...202033169164
epigenetic regulation of replication origin assembly: a role for histone h1 and chromatin remodeling factors.during early embryonic development in several metazoans, accurate dna replication is ensured by high number of replication origins. this guarantees rapid genome duplication coordinated with fast cell divisions. in xenopus laevis embryos this program switches to one with a lower number of origins at a developmental stage known as mid-blastula transition (mbt) when cell cycle length increases and gene transcription starts. consistent with this regulation, somatic nuclei replicate poorly when trans ...202033165968
synthesis of glun2a-selective nmda receptor antagonists with an electron-rich aromatic b-ring.glutamatergic n-methyl-d-aspartate (nmda) receptors are heterotetrameric ion channels that can be comprised of different subunits. glun2a subunit-containing nmda receptors are associated with diseases like anxiety, depression, and schizophrenia. however, the exact contribution of these nmda receptor subtypes is still unclear. to understand better the role of the glun2a-containing receptors, novel ligands were designed. in co-crystallization with the isolated binding site, tcn-201 (1) and analogs ...202033162207
trim-away mediated knock down uncovers a new function for lbh during gastrulation of xenopus laevis.we previously identified the protein lbh as necessary for cranial neural crest (cnc) cell migration in xenopus through the use of morpholinos. however, lbh is a maternally deposited protein and morpholinos achieve knockdowns through prevention of translation. in order to investigate the role of lbh in earlier embryonic events, we employed the new technique "trim-away" to degrade this maternally deposited protein. trim-away utilizes the e3 ubiquitin ligase trim21 to degrade proteins targeted with ...202033159936
kunitz-type peptides from the sea anemone heteractis crispa demonstrate potassium channel blocking and anti-inflammatory activities.the kunitz/bpti peptide family includes unique representatives demonstrating various biological activities. electrophysiological screening of peptides hcrg1 and hcrg2 from the sea anemone heteractis crispa on six kv1.x channel isoforms and insect shaker ir channel expressed in xenopus laevis oocytes revealed their potassium channels blocking activity. hcrg1 and hcrg2 appear to be the first kunitz-type peptides from sea anemones blocking kv1.3 with ic50 of 40.7 and 29.7 nm, respectively. in addit ...202033158163
development of antimicrobial peptides from amphibians.since the discovery of magainins from the skin secretions of the african toad xenopus laevis by michael zasloff in 1987, an increasing number of antimicrobial peptides (amps) has been identified in different anuran species and studied in detail [...].202033158031
antimicrobial peptide induced-stress renders staphylococcus aureus susceptible to toxic nucleoside analogs.cationic antimicrobial peptides (amps) are active immune effectors of multicellular organisms and are also considered as new antimicrobial drug candidates. one of the problems encountered when developing amps as drugs is the difficulty of reaching sufficient killing concentrations under physiological conditions. here, using pexiganan, a cationic peptide derived from a host defense peptide of the african clawed frog and the first amp developed into an antibacterial drug, we studied whether sub-le ...202033133056
nicotinic acetylcholine receptors in the synganglion of the tick ixodes ricinus: functional characterization using membrane microtransplantation.nicotinic acetylcholine receptors are an important class of excitatory receptors in the central nervous system of arthropods. in the ticks ixodes ricinus, the functional and pharmacological properties of nicotinic receptors located in their neurons are still unknown. the objective of this study was to characterize the pharmacological properties of tick nicotinic receptors using membrane microtransplantation in xenopus laevis oocytes and two-electrodes voltage clamp method. the membranes microtra ...202033120248
observation of nucleic acids inside living human cells by in-cell nmr spectroscopy.the intracellular environment is highly crowded with biomacromolecules such as proteins and nucleic acids. under such conditions, the structural and biophysical features of nucleic acids have been thought to be different from those in vitro. to obtain high-resolution structural information on nucleic acids in living cells, the in-cell nmr method is a unique tool. following the first in-cell nmr measurement of nucleic acids in 2009, several interesting insights were obtained using xenopus laevis ...202033110737
high affinity na+ transport by wheat hkt1;5 is blocked by k.the wheat sodium transporters tmhkt1;5-a and tahkt1;5-d are encoded by genes underlying the major shoot na+ exclusion loci nax2 and kna1 from triticum monococcum (tm) and triticum aestivum (ta), respectively. in contrast to hkt2 transporters that have been shown to exhibit high affinity k+-dependent na+ transport, hkt1 proteins have, with one exception, only been shown to catalyze low affinity na+ transport and no k+ transport. here, using heterologous expression in xenopus laevis oocytes we unc ...202033103046
x-box-binding protein 1 is required for pancreatic development in xenopus laevis.x-box-binding protein 1 (xbp1) is a protein containing the basic leucine zipper structure. it belongs to the camp-response element binding protein (creb)/activating transcription factor transcription factor family. as the main transcription factor, spliced xbp1 (xbp1s) participates in many physiological and pathological processes and plays an important role in embryonic development. previous studies showed that xbp1-knockout mice died because of pancreatic exocrine function deficiency, indicatin ...202033098302
sclerostin inhibits wnt signaling through tandem interaction with two lrp6 ectodomains.low-density lipoprotein receptor-related protein 6 (lrp6) is a coreceptor of the β-catenin-dependent wnt signaling pathway. the lrp6 ectodomain binds wnt proteins, as well as wnt inhibitors such as sclerostin (sost), which negatively regulates wnt signaling in osteocytes. although lrp6 ectodomain 1 (e1) is known to interact with sost, several unresolved questions remain, such as the reason why sost binds to lrp6 e1e2 with higher affinity than to the e1 domain alone. here, we present the crystal ...202033097721
rad21 is involved in corneal stroma development by regulating neural crest migration.previously, we identified rad21r450c from a peripheral sclerocornea pedigree. injection of this rad21 variant mrna into xenopus laevis embryos disrupted the organization of corneal stroma fibrils. to understand the mechanisms of rad21-mediated corneal stroma defects, gene expression and chromosome conformation analysis were performed using cells from family members affected by peripheral sclerocornea. both gene expression and chromosome conformation of cell adhesion genes were affected in cells ...202033096935
phosphoproteomic analysis of xenopus laevis reveals expression and phosphorylation of hypoxia-inducible pfkfb3 during dehydration.xenopus laevis tolerate dehydration when their environments evaporate during summer months. protein phosphorylation has previously shown to regulate important adaptations in x. laevis, including the transition to anaerobic metabolism. we therefore performed phosphoproteomic analysis of x. laevis to further elucidate the cellular and metabolic responses to dehydration. phosphoproteins were enriched in cellular functions and pathways related to glycolysis/gluconeogenesis, the tca cycle, and protei ...202033083755
derivation of proliferative islet1-positive cells during metamorphosis and wound response in xenopus.in mammalian hearts, cardiomyocytes retain a transient capacity to proliferate and regenerate following injury before birth, whereas they lose proliferative capacity immediately after birth. it has also been known that cardiac progenitor cells including islet1-positive cells do not contribute to the cardiac repair and regeneration in mammals. in contrast, hearts of zebrafish, amphibians and reptiles maintain a regenerative ability throughout life. here, we analyzed proliferative capacity of card ...202033070205
non-junctional role of cadherin3 in cell migration and contact inhibition of locomotion via domain-dependent, opposing regulation of rac1.classical cadherins are well-known adhesion molecules responsible for physically connecting neighboring cells and signaling this cell-cell contact. recent studies have suggested novel signaling roles for "non-junctional" cadherins (njcads); however, the function of cadherin signaling independent of cell-cell contacts remains unknown. in this study, mesendodermal cells and tissues from gastrula stage xenopus laevis embryos demonstrate that deletion of extracellular domains of cadherin3 (cdh3; for ...202033060598
scorpion toxin meunatxα-1 sensitizes primary nociceptors by selective modulation of voltage-gated sodium channels.venoms are a rich source of highly specific toxins, which allow the identification of novel therapeutic targets. we have now applied high content screening (hcs) microscopy to identify toxins that modulate pain sensitization signaling in primary sensory neurons of rat and elucidated the underlying mechanism. a set of venoms and fractions thereof were analyzed for their ability to activate type ii protein kinase a (pka-ii) and extracellular signal-regulated kinases (erk1/2). we identified meunatx ...202033051988
glutamate, d-(-)-2-amino-5-phosphonopentanoic acid, and n-methyl-d-aspartate do not directly modulate glycine receptors.replication studies play an essential role in corroborating research findings and ensuring that subsequent experimental works are interpreted correctly. a previously published paper indicated that the neurotransmitter glutamate, along with the compounds n-methyl-d-aspartate (nmda) and d-(-)-2-amino-5-phosphonopentanoic acid (ap5), acts as positive allosteric modulators of inhibitory glycine receptors. the paper further suggested that this form of modulation would play a role in setting the spina ...202033051383
whole-brain calcium imaging in larval xenopus.sensory systems detect environmental stimuli and transform them into electrical activity patterns interpretable by the central nervous system. en route to higher brain centers, the initial sensory input is successively transformed by interposed secondary processing centers. mapping the neuronal activity patterns at all of those stages is essential to understand sensory information processing. larval xenopus laevis is very well-suited for whole-brain imaging of neuronal activity. this is mainly d ...202033037078
elucidating the framework for specification and determination of the embryonic retina.how cell determination is regulated remains a major unsolved problem in developmental biology. the early embryonic rudiments of many tissues and organs are difficult or impossible to identify, isolate and study at the time when determination occurs. we have examined the commitment process leading to retina formation in xenopus laevis, where presumptive eye tissue can be identified and studied to assay its biological properties during the events leading up to determination. we find that for the r ...202033031807
microtubule-dependent pushing forces contribute to long-distance aster movement and centration in xenopus laevis egg extracts.during interphase of the eukaryotic cell cycle, the microtubule (mt) cytoskeleton serves as both a supportive scaffold for organelles and an arborized system of tracks for intracellular transport. at the onset of mitosis, the position of the astral mt network, specifically its center, determines the eventual location of the spindle apparatus and ultimately the cytokinetic furrow. positioning of the mt aster often results in its movement to the center of a cell, even in large blastomeres hundreds ...202033026931
cross-talk between p2x and nmda receptors.purinergic p2x receptors (p2x) are atp-gated ion channels widely expressed in the cns. while the direct contribution of p2x to synaptic transmission is uncertain, p2x reportedly affect n-methyl-d-aspartate receptor (nmdar) activity, which has given rise to competing theories on the role of p2x in the modulation of synapses. however, p2x have also been shown to participate in receptor cross-talk: an interaction where one receptor (e.g., p2x2) directly influences the activity of another (e.g., nic ...202033003406
dna content contributes to nuclear size control in xenopus laevis.cells adapt to drastic changes in genome quantity during evolution and cell division by adjusting the nuclear size to exert genomic functions. however, the mechanism by which dna content within the nucleus contributes to controlling the nuclear size remains unclear. here, we experimentally evaluated the effects of dna content by utilizing cell-free xenopus egg extracts and imaging of in vivo embryos. upon manipulation of dna content while maintaining cytoplasmic effects constant, both plateau si ...202032997613
torc1 selectively regulates synaptic maturation and input convergence in the developing visual system.newly synthesized proteins support the development of functional neural circuits and previous work has suggested that dysregulated translation mediates certain forms of autism spectrum disorder (asd). here, we investigated the role of target of rapamycin complex 1 (torc1) in synaptic and dendritic development in vivo in the retinotectal system of xenopus laevis tadpoles. we found that torc1 signaling regulates dendritic growth and branching and that acute over-activation of torc1 by rheb overexp ...202032996262
a survey of barley pip aquaporin ionic conductance reveals ca2+-sensitive hvpip2;8 na+ and k+ conductance.some plasma membrane intrinsic protein (pip) aquaporins can facilitate ion transport. here we report that one of the 12 barley pips (pip1 and pip2) tested, hvpip2;8, facilitated cation transport when expressed in xenopus laevis oocytes. hvpip2;8-associated ion currents were detected with na+ and k+, but not cs+, rb+, or li+, and was inhibited by ba2+, ca2+, and cd2+ and to a lesser extent mg2+, which also interacted with ca2+. currents were reduced in the presence of k+, cs+, rb+, or li+ relativ ...202032992595
inferring a complete genotype-phenotype map from a small number of measured phenotypes.understanding evolution requires detailed knowledge of genotype-phenotype maps; however, it can be a herculean task to measure every phenotype in a combinatorial map. we have developed a computational strategy to predict the missing phenotypes from an incomplete, combinatorial genotype-phenotype map. as a test case, we used an incomplete genotype-phenotype dataset previously generated for the malaria parasite's 'chloroquine resistance transporter' (pfcrt). wild-type pfcrt (pfcrt3d7) lacks signif ...202032991585
the mechanism of nmda receptor hyperexcitation in high pressure helium and hyperbaric oxygen.professional divers exposed to pressures greater than 1.1 mpa may suffer from the high pressure neurological syndrome (hpns). divers who use closed-circuit breathing apparatus face the risk of cns hyperbaric oxygen toxicity (hbotox). both syndromes are characterized by reversible cns hyperexcitability, accompanied by cognitive and motor deficits. previous studies have demonstrated that the hyperexcitability of hpns is induced mainly by nmda receptors (nmdars). in our recent studies, we demonstra ...202032982789
in-cell nmr spectroscopy of functional riboswitch aptamers in eukaryotic cells.we report here the in-cell nmr-spectroscopic observation of the binding of the cognate ligand 2'-deoxyguanosine to the aptamer domain of the bacterial 2'-deoxyguanosine-sensing riboswitch in eukaryotic cells, namely xenopus laevis oocytes and in human hela cells. the riboswitch is sufficiently stable in both cell types to allow for detection of binding of the ligand to the riboswitch. most importantly, we show that the binding mode established by in vitro characterization of this prokaryotic rib ...202032975353
design, synthesis, and in vitro evaluation of p2x7 antagonists.the p2x7 receptor is a promising target for the treatment of various diseases due to its significant role in inflammation and immune cell signaling. this work describes the design, synthesis, and in vitro evaluation of a series of novel derivatives bearing diverse scaffolds as potent p2x7 antagonists. our approach was based on structural modifications of reported (adamantan-1-yl)methylbenzamides able to inhibit the receptor activation. the adamantane moieties and the amide bond were replaced, an ...202032964578
endoparasites infecting exotic captive amphibian pet and zoo animals (anura, caudata) in germany.alongside exotic reptiles, amphibians, such as toads, frogs, salamanders, and newts, are nowadays considered popular pets worldwide. as reported for other exotic pet animals, amphibians are known to harbor numerous gastrointestinal parasites. nonetheless, very little data are available on captive amphibian parasitic diseases. in this study, we applied direct saline fecal smears (dsfs) to examine in total 161 stool samples from 41 different amphibian species belonging to the orders anura and caud ...202032960371
amiodarone bioconcentration and suppression of metamorphosis in xenopus.trace concentrations of a number of pharmaceutically active compounds have been detected in the aquatic environment in many countries, where they are thought to have the potential to exert adverse effects on non-target organisms. amiodarone (amd) is one such high-risk compound commonly used in general hospitals. amd is known to alter normal thyroid hormone (th) function, although little information is available regarding the specific mechanism by which this disruption occurs. anuran tadpole meta ...202032956954
aquaporin expression in the alimentary canal of the honey bee apis mellifera l. (hymenoptera: apidae) and functional characterization of am_eglp 1.aquaporins (aqp) are a family of plasma membrane proteins responsible for water transport through cell membranes. they are differentially expressed in different parts of the alimentary canal of insects where they regulate water transport. these proteins have been studied in detail in some insects, but few data are available for aquaporins of the honey bee, apis mellifera. we used quantitative pcr to study the expression of six putative aquaporin genes in forager honey bees. we found differential ...202032956406
do muscle contractile properties drive differences in locomotor performance in invasive populations of xenopus laevis in france?jumping and swimming are key locomotor traits in frogs intimately linked to survival and dispersal. french populations of the frog xenopus laevis from the invasion front are known to possess greater terrestrial locomotor endurance. here, we tested whether individuals from the invasion front show differences in their muscle physiology that may underlie the observed whole-organism performance differences. we measured muscle contractile properties of the isolated gastrocnemius muscle in vitro, incl ...202032955613
effect of 158 herbal remedies on human trpv1 and the two-pore domain potassium channels kcnk2, 3 and 9.herbal medicines are used to treat a broad number of maladies. however, the pharmacological profile of most remedies is poorly understood. we investigated the effect of herbal remedies from kampo, traditional chinese medicine (tcm) and other phytotherapies on human two-pore domain potassium channels (kcnk channels; trek-1, task-1 and task-3) as well as the human trpv1 channel. kcnk channels are responsible for the background potassium current of excitable cells, thus essential for the maintenanc ...202032953560
exposure impacts of environmentally relevant concentrations of a glufosinate ammonium herbicide formulation on larval development and thyroid histology of xenopus laevis.thyroid hormones play critical roles in body growth and development as well as reproduction. they also influence the activities of a wider variety of tissues and biological functions, such as osmoregulation, metabolism, and especially metamorphosis in organisms, such as frogs. these complex activities of thyroid hormones are prone to disruption by agricultural pesticides, often leading to modulation of growth and the reproductive system in particular. these substances include glufosinate ammoniu ...202032948887
an integrated approach to assess the sublethal effects of colloidal gold nanorods in tadpoles of xenopus laevis.gold nanorods (aunr) have been explored for many applications, including innovative nanomedicines, which also might contribute to its increase in the environment, namely due to inadequate disposable of wastes into aquatic environments. early-life stages of amphibians are usually aquatic and sensitive to chemical contamination. accordingly, this study aimed to determine the sublethal effects of ctab functionalized aunr on xenopus laevis tadpoles. as such, tadpoles were exposed to serial concentra ...202032947686
sorafenib activity and disposition in liver cancer does not depend on organic cation transporter 1.systemic therapy of advanced hepatocellular carcinoma (hcc) with the small-molecule multikinase inhibitor sorafenib is associated with large interindividual pharmacokinetic variability and unpredictable side effects potentially requiring dose reduction or treatment termination. organic cation transporter (oct1; gene slc22a1) has been proposed as a clinical biomarker of hcc response. because proof is lacking that oct1 transports sorafenib, we used a combinatorial approach to define how oct1 contr ...202031350763
the hkt transporter hvhkt1;5 negatively regulates salt tolerance.maintaining low intracellular na+ concentrations is an essential physiological strategy in salt stress tolerance in most cereal crops. here, we characterized a member of the high-affinity k+ transporter (hkt) family in barley (hordeum vulgare), hvhkt1;5, which negatively regulates salt tolerance and has different functions from its homology in other cereal crops. hvhkt1;5 encodes a plasma membrane protein localized to root stele cells, particularly in xylem parenchyma cells adjacent to the xylem ...202031690708
simple method to characterize the ciliary proteome of multiciliated cells.motile cilia of multiciliated epithelial cells have important roles in animal development and cell homeostasis. although several studies have identified and reported proteins localized in this complex organelle and the related immotile primary cilia from various cell types, it is still challenging to isolate high quantities of ciliary proteins for proteomic analysis. in this study, african clawed frog (xenopus laevis) embryos, which have many multiciliated cells in the epidermis, were treated wi ...202031689115
complement c1q subunit molecules from xenopus laevis possess conserved function in c1q-immunoglobulin interaction.complement component 1q (c1q), together with c1r and c1s to form c1, recognize and bind immune complex to initiate the classical complement pathway. in this study, c1q subunit molecules (xlc1qa, xlc1qb, xlc1qc) were cloned and analyzed from xenopus laevis (x. laevis). the open reading frame (orf) of xlc1qa is 819 bp of nucleotide sequence encoding 272 amino acids, the orf of xlc1qb is 711 bp encoding 236 aa, and the xlc1qc is consists of 732 bp encoding 243 aa. the deduced amino acid sequences c ...202031678076
pannexin 1 activation and inhibition is permeant-selective.the large-pore channel pannexin 1 (panx1) is expressed in many cell types and can open upon different, yet not fully established, stimuli. panx1 permeability is often inferred from channel permeability to fluorescent dyes, but it is currently unknown whether dye permeability translates to permeability to other molecules. cell shrinkage and c-terminal cleavage led to a panx1 open-state with increased permeability to atomic ions (current), but did not alter ethidium uptake. panx1 inhibitors affect ...202031698505
biochemical responses revealed in an amphibian species after exposure to a forgotten contaminant: an integrated biomarker assessment.vanadium is a metal whose toxicity towards terrestrial and aquatic species has been under-reported to date.. the biochemical responses of vanadium in amphibian species have not been determined. to establish the effects of vanadium (v) on exposed adult xenopus laevis, acute and chronic exposures were conducted, and biomarker analyses were performed on liver and muscle tissues from exposed frogs. biomarkers of exposure, such as acetylcholinesterase (ache) and metallothioneins (mt), were analysed. ...202031629886
extracellular lysine 38 plays a crucial role in ph-dependent transport via human monocarboxylate transporter 1.human monocarboxylate transporters (hmcts) are expressed in many tissues and mediate the transport of various substrates across the plasma membrane. among hmcts, hmct1-4 cotransport h+ with monocarboxylates such as pyruvate and l-lactate, implying that these proteins recognize both substrate and h+. however, the mechanism of translocation, and particularly that of hmct1 ph-dependent transport, remains largely unknown. this study aimed at identifying residues involved in the ph dependence of hmct ...202031593685
cytosolic gaba inhibits anion transport by wheat almt1.anion transport by aluminium-activated malate transporter (almt) proteins is negatively regulated by gamma-aminobutyric acid (gaba), which increases in concentration during stress. here, the interaction between gaba and wheat (triticum aestivum, ta) taalmt1 heterologously-expressed in xenopus laevis oocytes was investigated. gaba inhibited anion transport by taalmt1 in membrane patches from the cytosolic, not extracellular membrane face, via a reduction in open probability (npopen ), not an inhi ...202031591723
morpholino studies in xenopus brain development.antisense morpholino oligonucleotides (mos) have become a valuable method to knockdown protein levels, to block with mrna splicing and to interfere with mirna function. mos are widely used to alter gene expression in development of xenopus and zebrafish, where they are typically injected into the fertilized egg or blastomeres. here we present methods to use electroporation to target delivery of mos to the central nervous system of xenopus laevis or xenopus tropicalis tadpoles. briefly, mo electr ...202031552666
odontomas in frogs.odontomas are variably differentiated, hamartoma-like proliferations of odontogenic epithelium, pulp ectomesenchyme (odontoblasts), and dental matrix. frogs are polyphyodont and homodont. their teeth also differ from mammals in that they are restricted to the upper jaw in adults and lack a periodontal ligament and cementum, attaching directly to the underlying bone. odontomas were identified in an african clawed frog (xenopus laevis), a false tomato frog (dyscophus guineti), and a tomato frog of ...202031551010
smooth muscle in cardiac chambers is common in turtles and extensive in the emydid turtle, trachemys scripta.a prominent layer of smooth muscle lining the luminal side of the atria of freshwater turtles (emydidae) was described more than a century ago. we recently demonstrated that this smooth muscle provides a previously unrecognized mechanism to change cardiac output in the emydid red-eared slider (trachemys scripta) that possibly contributes to their tremendous diving capacity. the purpose of the present immunohistochemical study was firstly to screen major groups of vertebrates for the presence of ...202031509333
the expression of key guidance genes at a forebrain axon turning point is maintained by distinct fgfr isoforms but a common downstream signal transduction mechanism.during development the axons of neurons grow toward and locate their synaptic partners to form functional neural circuits. axons do so by reading a map of guidance cues expressed by surrounding tissues. guidance cues are expressed at a precise space and time, but how guidance cue expression is regulated, and in a coordinated manner, is poorly understood. semaphorins (semas) and slits are families of molecular ligands that guide axons. we showed previously that fibroblast growth factor (fgf) sign ...202030993182
coexposure to environmental concentrations of cis-bifenthrin and graphene oxide: adverse effects on the nervous system during metamorphic development of xenopus laevis.despite the great concerns associated with the combined biological effects of nanoparticles and insecticides, the current understanding of the corresponding ecological risks remains limited. xenopus laevis (x. laevis) tadpoles were exposed to various concentrations of typical pyrethroid (cis-bifenthrin; cis-bf), either alone or in combination with graphene oxide (go), for 21 days. the presence of go resulted in increased bioconcentration of cis-bf and a higher 1s-enantiomer fraction. exposure to ...202031425913
leishmania heme uptake involves lmflvcrb, a novel porphyrin transporter essential for the parasite.leishmaniasis comprises a group of neglected diseases caused by the protozoan parasite leishmania spp. as is the case for other trypanosomatid parasites, leishmania is auxotrophic for heme and must scavenge this essential compound from its human host. in mammals, the slc transporter flvcr2 mediates heme import across the plasma membrane. herein we identify and characterize leishmania major flvcrb (lmflvcrb), the first member of the flvcr family studied in a non-metazoan organism. this protein lo ...202031372684
adverse effects of fly ashes used as immobilizing agents for highly metal-contaminated soils on xenopus laevis oocytes survival and maturation-a study performed in the north of france with field soil extracts.amphibians are now recognized as the most endangered group. one of this decline causes is the degradation of their habitat through direct contamination of water, soil leaching, or runoff from surrounding contaminated soils and environments. in the north of france, the extensive industrial activities resulted in massive soil contamination by metal compounds. mineral amendments were added to soils to decrease trace metal mobility. because of the large areas to be treated, the use of inexpensive in ...202030875069
effects of glyphosate and a commercial formulation roundup® exposures on maturation of xenopus laevis oocytes.pesticides are often found at high concentrations in small ponds near agricultural field where amphibians are used to live and reproduce. even if there are many studies on the impacts of phytopharmaceutical active ingredients in amphibian toxicology, only a few are interested in the earlier steps of their life cycle. while their populations are highly threatened with extinction. the aim of this work is to characterize the effects of glyphosate and its commercial formulation roundup® gt max on th ...202030835066
lin28b increases neural crest cell migration and leads to transformation of trunk sympathoadrenal precursors.the rna-binding protein lin28b regulates developmental timing and determines stem cell identity by suppressing the let-7 family of micrornas. postembryonic reactivation of lin28b impairs cell commitment to differentiation, prompting their transformation. in this study, we assessed the extent to which ectopic lin28b expression modulates the physiological behavior of neural crest cells (ncc) and governs their transformation in the trunk region of developing embryos. we provide evidence that the ov ...202031601998
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 ...201931598865
enhanced visual experience rehabilitates the injured brain in xenopus tadpoles in an nmdar-dependent manner.traumatic brain injuries introduce functional and structural circuit deficits that must be repaired for an organism to regain function. we developed an injury model in which xenopus laevis tadpoles are given a penetrating stab wound that damages the optic tectal circuit and impairs visuomotor behavior. in tadpoles, as in other systems, injury induces neurogenesis. the newly generated neurons are thought to integrate into the existing circuit; however, whether they integrate via the same mechanis ...201930517041
sr 57227a is a partial agonist/partial antagonist of 5-ht3 receptor and inhibits subsequent 5-ht- or sr 57227a-induced 5-ht3 receptor current.the serotonin (5-hydroxytryptamine) type 3 (5-ht3) receptors are transmembrane ligand-gated ion channels. although several 5-ht3 receptor agonists have been used as preclinical tools, sr 57227a is the most commonly used 5-ht3 receptor agonist with the ability to cross the blood brain barrier. however, the precise pharmacological profile of sr 57227a remains unclear. therefore, we examined the pharmacological profile of sr 57227a at the 5-ht3a and 5-ht3ab receptors. we microinjected xenopus laevi ...201930509492
involvement of epigenetic modifications in thyroid hormone-dependent formation of adult intestinal stem cells during amphibian metamorphosis.amphibian metamorphosis has long been used as model to study postembryonic development in vertebrates, a period around birth in mammals when many organs/tissues mature into their adult forms and is characterized by peak levels of plasma thyroid hormone (t3). of particular interest is the remodeling of the intestine during metamorphosis. in the highly-related anurans xenopus laevis and xenopus tropicalis, this remodeling process involves larval epithelial cell death and de novo formation of adult ...201930472386
solid lipid nanoparticles for the delivery of anti-microbial oligonucleotides.novel alternatives to antibiotics are urgently needed for the successful treatment of antimicrobial resistant (amr) infections. experimental antibacterial oligonucleotide therapeutics, such as transcription factor decoys (tfd), are a promising approach to circumvent amr. however, the therapeutic potential of tfd is contingent upon the development of carriers that afford efficient dna protection against nucleases and delivery of dna to the target infection site. as a carrier for tfd, here we pres ...201930468838
expression pattern and histone acetylation of energy metabolic genes in xenopus laevis liver in response to diet statuses.amphibians can survive without food for relatively longer periods by reducing the locomotor activity and metabolic rate and can recover quickly with refeeding from a dormant state. to clarify the molecular mechanism underlying this survival strategy, we investigated serum biochemical parameters, the transcript levels of energy metabolic genes, and global and gene-specific histone modifications in the liver of adult male xenopus laevis, which were fed, fasted, or refed after fasting. glucose, tri ...201930460762
how thyroid hormones and their inhibitors affect cartilage growth and shape in the frog xenopus laevis.understanding how skeleton changes shape in ontogeny is fundamental to understanding how its shape diversifies in phylogeny. amphibians pose a special case because their jaw and throat skeleton consists of cartilages that are dramatically reshaped midway through life to support new feeding and breathing styles. although amphibian metamorphosis is commonly studied by immersing larvae in thyroid hormones (th), how individual cartilages respond to th is poorly understood. this study documents the e ...201930456781
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