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identification and functional characterization of the chloride channel gene, gsclc-c2 from wild soybean.the anionic toxicity of plants under salt stress is mainly caused by chloride (cl-). thus cl- influx, transport and their regulatory mechanisms should be one of the most important aspects of plant salt tolerance studies, but are often sidelined by the focus on sodium (na+) toxicity and its associated adaptations. plant chloride channels (clcs) are transport proteins for anions including cl- and nitrate (no3-), and are critical for nutrition uptake and transport, adjustment of cellular turgor, st ...201930935372
more than just a bandage: closing the gap between injury and appendage regeneration.the remarkable regenerative capabilities of amphibians have captured the attention of biologists for centuries. the frogs xenopus laevis and xenopus tropicalis undergo temporally restricted regenerative healing of appendage amputations and spinal cord truncations, injuries that are both devastating and relatively common in human patients. rapidly expanding technological innovations have led to a resurgence of interest in defining the factors that enable regenerative healing, and in coupling thes ...201930800076
the wnt inhibitor dkk1 is required for maintaining the normal cardiac differentiation program in xenopus laevis.wnt proteins can activate different intracellular signaling pathways. these pathways need to be tightly regulated for proper cardiogenesis. the canonical wnt/β-catenin inhibitor dkk1 has been shown to be sufficient to trigger cardiogenesis in gain-of-function experiments performed in multiple model systems. loss-of-function studies however did not reveal any fundamental function for dkk1 during cardiogenesis. using xenopus laevis as a model we here show for the first time that dkk1 is required f ...201930797757
using xenopus laevis oocytes to functionally characterize plant transporters.functionally characterizing plant membrane transport proteins is challenging. typically, heterologous systems are used to study them. immature eggs (oocytes) of the south african clawed frog xenopus laevis are considered an ideal expression system for such studies. these large oocytes have a low number of endogenous transport systems in their plasma membranes and highly express foreign mrna; the oocyte plasma membrane is the default destination of integral membrane proteins that lack recognized ...201930707001
anillin regulates epithelial cell mechanics by structuring the medial-apical actomyosin network.cellular forces sculpt organisms during development, while misregulation of cellular mechanics can promote disease. here, we investigate how the actomyosin scaffold protein anillin contributes to epithelial mechanics in xenopus laevis embryos. increased mechanosensitive recruitment of vinculin to cell-cell junctions when anillin is overexpressed suggested that anillin promotes junctional tension. however, junctional laser ablation unexpectedly showed that junctions recoil faster when anillin is ...201930702429
a microarray-based comparative analysis of gene expression profiles in thyroid glands in amphibian metamorphosis: differences in effects between chemical exposure and food restriction.tadpoles during metamorphosis are sensitive to chemical exposure as shown in the amphibian metamorphosis assay, which is a method to detect effects of chemicals on the functions of hypothalamus-pituitary-thyroid axis. the present study reports existence of different modes of action between pyriproxyfen (pyr) and 6-propyl-2-thiouracil (ptu) under different feeding conditions based on gene expression profiles (transcriptomics) in the thyroid glands of tadpoles of the african clawed frog, xenopus l ...201930883854
effect of nucleosome assembly on alkylation by a dynamic electrophile.quinone methides are reactive electrophiles that are generated during metabolism of various drugs, natural products, and food additives. their chemical properties and cellular effects have been described previously, and now their response to packaging dna in a nucleosome core is described. a model bisquinone methide precursor (bisqmp) was selected based on its ability to form reversible adducts with guanine n7 that allow for their redistribution and transfer after quinone methide regeneration. a ...201930882212
dynamin binding protein is required for xenopus laevis kidney development.the adult human kidney contains over one million nephrons, with each nephron consisting of a tube containing segments that have specialized functions in nutrient and water absorption and waste excretion. the embryonic kidney of xenopus laevis consists of a single functional nephron composed of regions that are analogous to those found in the human nephron, making it a simple model for the study of nephrogenesis. the exocyst complex, which traffics proteins to the cell membrane in vesicles via cd ...201930863317
foxn3 is necessary for the development of the interatrial septum, the ventricular trabeculae and the muscles at the head/trunk interface in the african clawed frog, xenopus laevis (lissamphibia: anura: pipidae).fox genes are a large family of transcription factors that play diverse roles in the immune system, metabolism, cancer, cell cycle, and animal development. it has been shown that foxn3 is indispensable for normal craniofacial development in the mouse and the african clawed frog, xenopus laevis. morpholino-mediated knockdown of foxn3 in x. laevis delays overall development of early tadpole stages and causes eye defects, the absence of some cranial nerve branches, and malformations of the cranial ...201930859697
induction of a spindle-assembly-competent m phase in xenopus egg extracts.normal mitotic spindle assembly is a prerequisite for faithful chromosome segregation and unperturbed cell-cycle progression. precise functioning of the spindle machinery relies on conserved architectural features, such as focused poles, chromosome alignment at the metaphase plate, and proper spindle length. these morphological requirements can be achieved only within a compositionally distinct cytoplasm that results from cell-cycle-dependent regulation of specific protein levels and specific po ...201930930041
trace, machine learning of signal images for trace-sensitive mass spectrometry: a case study from single-cell metabolomics.recent developments in high-resolution mass spectrometry (hrms) technology enabled ultrasensitive detection of proteins, peptides, and metabolites in limited amounts of samples, even single cells. however, extraction of trace-abundance signals from complex data sets ( m/ z value, separation time, signal abundance) that result from ultrasensitive studies requires improved data processing algorithms. to bridge this gap, we here developed "trace", a software framework that incorporates machine lear ...201930929422
recovery of the xenopus laevis heart from ros-induced stress utilizes conserved pathways of cardiac regeneration.urodele amphibians and some fish are capable of regenerating up to a quarter of their heart tissue after cardiac injury. while many anuran amphibians like xenopus laevis are not capable of such feats, they are able to repair lesser levels of cardiac damage, such as that caused by oxidative stress, to a far greater degree than mammals. using an optogenetic stress induction model that utilizes the protein killerred, we have investigated the extent to which mechanisms of cardiac regeneration are co ...201930924142
ursodeoxycholic acid inhibits uptake and vasoconstrictor effects of taurocholate in human placenta.intrahepatic cholestasis of pregnancy (icp) causes increased transfer of maternal bile acids to the fetus and an increased incidence of sudden fetal death. treatment includes ursodeoxycholic acid (udca), but it is not clear if udca protects the fetus. this study explores the placental transport of the bile acid taurocholate (tc) by the organic anion-transporting polypeptide, (oatp)4a1, its effects on the placental proteome and vascular function, and how these are modified by udca. various method ...201930922127
xenopus laevis as a bioindicator of endocrine disruptors in the region of central chile.one of the direct causes of biodiversity loss is environmental pollution resulting from the use of chemicals. different kinds of chemicals, such as persistent organic pollutants and some heavy metals, can be endocrine disruptors, which act at low doses over a long period of time and have a negative effect on the reproductive and thyroid system in vertebrates worldwide. research on the effects of endocrine disruptors and the use of bioindicators in neotropical ecosystems where pressure on biodive ...201931422435
changes in ca2+ removal can mask the effects of geometry during ip3r mediated ca2+ signals.calcium (ca2+) signals are ubiquitous. most intracellular ca2+ signals involve the release of ca2+ from the endoplasmic reticulum (er) through inositol 1,4,5-trisphosphate receptors (ip3rs). the non-uniform spatial organization of ip3rs and the fact that their individual openings are coupled via cytosolic ca2+ are key factors for the variety of spatio-temporal distributions of the cytosolic [ca2+] and the versatility of the signals. in this paper we combine experiments performed in untreated and ...201931417423
gaining insights in the nutritional metabolism of amphibians: analyzing body nutrient profiles of the african clawed frog, xenopus laevis.whole bodies of xenopus laevis (n = 19) were analysed for chemical composition and morphometrics. the nutrient profile (macronutrients, amino acids, fatty acids and minerals) was evaluated by sex; interactions among variables with body weights and lengths, and comparisons made with different species of marine and fresh water fish. significant differences were found in morphometric measurements, water content, several minerals and fatty acids between sexes of x. laevis. amino acid profiles differ ...201931410305
novel vectors for functional interrogation of xenopus orfeome coding sequences.the current xenopus orfeome contains ~10,250 validated, full-length cdna sequences without stop codons from xenopus laevis and ~3,970 from xenopus tropicalis cloned into gateway-compatible entry vectors. to increase the utility of the orfeome, we have constructed the gateway-compatible destination vectors pdxtp and pdxtr, which in combination can control the spatial and temporal expression of any open reading frame (orf). pdxtp receives a promoter/enhancer of interest, which controls the spatial ...201931403250
comparative embryonic spatio-temporal expression profile map of the xenopus p2x receptor family.p2x receptors are atp-gated cations channels formed by the homo or hetero-trimeric association from the seven cloned subunits (p2x1-7). p2x receptors are widely distributed in different organs and cell types throughout the body including the nervous system and are involved in a large variety of physiological but also pathological processes in adult mammals. however, their expression and function during embryogenesis remain poorly understood. here, we report the cloning and the comparative expres ...201931402854
identification of shaker k+ channel family members in rosaceae and a functional exploration of pbrkat1.pbrkat1, which is inhibited by external na+ in xenopus laevis oocytes, is characterized as encoding a typical inward rectifying channel that is mainly expressed in guard cells. potassium (k+) is the most abundant cation in plant cells necessary for plant growth and development. the uptake and transport of k+ are mainly completed through transporters and channels, and the shaker family genes are the most studied k+ channels in plants. however, there is far less information about this family in ro ...201931523779
radiographic and ultrasonographic appearance of pneumonia in a frog.a 12-year-old female african clawed frog (xenopus laevis) displayed lethargy and anorexia for 1 week. radiographs detected a moderately reduced volume of aerated lung with lobulated margins with the left lung predominantly affected. transcelomic ultrasound revealed marked consolidation of the left lung. postmortem examination confirmed suppurative and histiocytic pneumonia, worse in the left lung, caused by mycobacterium chelonae. given that amphibian pulmonary consolidation and celomic effusion ...201931392794
polyamine biosynthesis in xenopus laevis: the xlazin2/xlodc2 gene encodes a lysine/ornithine decarboxylase.ornithine decarboxylase (odc) is a key enzyme in the biosynthesis of polyamines, organic cations that are implicated in many cellular processes. the enzyme is regulated at the post-translational level by an unusual system that includes antizymes (azs) and antizyme inhibitors (azins). most studies on this complex regulatory mechanism have been focused on human and rodent cells, showing that azins (azin1 and azin2) are homologues of odc but devoid of enzymatic activity. little is known about xenop ...201931509528
increasing nitroxide lifetime in cells to enable in-cell protein structure and dynamics measurements by electron spin resonance spectroscopy.there is increasing evidence that the stability, structure, dynamics, and function of many proteins differ in cells versus in vitro. the determination of protein structure and dynamics within the native cellular environment may lead to better understanding of protein behavior. electron spin resonance (esr) has emerged as a technique that can report on protein structure and dynamics within cells. nitroxide based spin labels are capable of reporting on protein dynamics, structure, and backbone fle ...201930550988
dual cationic-anionic profiling of metabolites in a single identified cell in a live xenopus laevis embryo by microprobe ce-esi-ms.in situ capillary microsampling with capillary electrophoresis (ce) electrospray ionization (esi) mass spectrometry (ms) enabled the characterization of cationic metabolites in single cells in complex tissues and organisms. for deeper coverage of the metabolome and metabolic networks, analytical approaches are needed that provide complementary detection for anionic metabolites, ideally using the same instrumentation. described here is one such approach that enables sequential cationic and anioni ...201930542678
a xenopus tadpole alternative model to study innate-like t cell-mediated anti-mycobacterial immunity.owing to the high incidence of multi-drug resistance and challenges posed by the complex and long duration of treatments, mycobacterium tuberculosis (mtb) infections remain a significant clinical burden, which would benefit from development of novel immuno-therapeutic-based treatment strategies. among early immune effectors, invariant or innate-like (i)t cells are attracting attention because of their potential regulatory activity, which can shape anti-mycobacterial immune responses. unlike conv ...201930521838
lysine demethylase 3a in craniofacial and neural development during xenopus embryogenesis.epigenetic modifier lysine demethylase 3a (kdm3a) specifically demethylates mono‑ and di‑methylated ninth lysine of histone 3 and belongs to the jumonji domain‑containing group of demethylases. kdm3a serves roles during various biological and pathophysiological processes, including spermatogenesis and metabolism, determination of sex, androgen receptor‑mediated transcription and embryonic carcinoma cell differentiation. in the present study, physiological functions of kdm3a were evaluated during ...201930569092
ospht1;3 mediates uptake, translocation, and remobilization of phosphate under extremely low phosphate regimes.plant roots rely on inorganic orthophosphate (pi) transporters to acquire soluble pi from soil solutions that exists at micromolar levels in natural ecosystems. here, we functionally characterized a rice (oryza sativa) pi transporter, os phosphate transporter-1;3 (ospht1;3), that mediates pi uptake, translocation, and remobilization. ospht1;3 was directly regulated by os phosphate starvation response-2 and, in response to pi starvation, showed enhanced expression in young leaf blades and shoot b ...201930567970
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
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
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
class a scavenger receptors mediate extracellular dsrna sensing, leading to downstream antiviral gene expression in a novel american toad cell line, bufotad.viral double-stranded (ds)rna is a potent pathogen-associated molecular pattern (pamp), capable of inducing a strong antiviral state within the cell, protecting the cell from virus infection. in mammals and fish, sensing extracellular dsrna is mediated by cell-surface class a scavenger receptors (sr-as). currently, very little is known about sr-as in amphibians, including: sequence, expression patterns and function. to this end, sr-a expression and function was studied in a novel american toad ( ...201930452932
proteolytic activation of bmps: analysis of cleavage in xenopus oocytes and embryos.bone morphogenetic proteins (bmps) are synthesized as inactive precursors that are cleaved to generate active ligands, along with prodomain fragments that can modulate growth factor activity. here we provide three protocols that can be used to examine the process of proteolytic activation of bmps. the first protocol describes how to generate radiolabeled bmp precursor proteins in xenopus oocytes and then analyze the time course of precursor cleavage by recombinant enzymes in vitro. the second pr ...201930414129
radiobiological characteristics of descendant progeny of fish and amphibian cells that survive the initial ionizing radiation dose.to evaluate the development of delayed lethal mutations, the production of medium borne lethal bystander signals, and the acquirement of radiosensitive or radioresistant traits in distant descendant progeny of fish and amphibian cells surviving ionizing radiation materials and methods: american eel brain endothelial cells (eelb) and african clawed frog epithelial cells (a6) were initially irradiated with gamma rays at 0.5 gy or 2 gy. ionizing radiation (ir)-surviving cells were grown for 27 popu ...201930530089
microtransplantation of human brain receptors into oocytes to tackle key questions in drug discovery.it is important in drug discovery to demonstrate that activity of novel drugs found by screening on recombinant receptors translates to activity on native human receptors in brain areas affected by disease. in this review, we summarise the development and use of the microtransplantation technique. native receptors are reconstituted from human brain tissues into oocytes from the frog xenopus laevis where they can be functionally assessed. oocytes microtransplanted with hippocampal tissue from an ...201930395928
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
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
comprehensive analysis of formin localization in xenopus epithelial cells.reorganization of the actin cytoskeleton is crucial for cellular processes, including cytokinesis and cell-cell junction remodeling. formins are conserved processive actin-polymerizing machines that regulate actin dynamics by nucleating, elongating, and bundling linear actin filaments. because the formin family is large, with at least 15 members in vertebrates, there have not been any comprehensive studies examining formin localization and function within a common cell type. here, we characteriz ...201930379611
anticipation of food intake induces phosphorylation switch to regulate basolateral amino acid transporter lat4 (slc43a2) function.amino acid absorption requires luminal uptake into and subsequent basolateral efflux out of epithelial cells, with the latter step being critical to regulate the intracellular concentration of the amino acids. the basolateral essential neutral amino acid uniporter lat4 (slc43a2) has been suggested to drive the net efflux of non-essential and cationic amino acids via parallel amino acid antiporters by recycling some of their substrates; its deletion has been shown to cause defective postnatal gro ...201930379325
a modified tripeptide motif of rs1 (rsc1a1) down-regulates exocytotic pathways of human na+-d-glucose cotransporters sglt1, sglt2, and glucose sensor sglt3 in the presence of glucose.a domain of protein rs1 (rsc1a1) called rs1-reg down-regulates the plasma membrane abundance of na+-d-glucose cotransporter sglt1 by blocking the exocytotic pathway at the trans-golgi. this effect is blunted by intracellular glucose but prevails when serine in a qsp (gln-ser-pro) motif is replaced by glutamate [rs1-reg(s20e)]. rs1-reg binds to ornithine decarboxylase (odc) and inhibits odc in a glucose-dependent manner. because the odc inhibitor difluoromethylornithine (dfmo) acts like rs1-reg(s ...201930355744
functional studies of transcriptional cofactors via microinjection-mediated gene editing in xenopus.the anuran xenopus laevis has been studied for decades as a model for vertebrate cell and developmental biology. more recently, the highly related species xenopus tropicalis has offered the opportunity to carry out genetic studies due to its diploid genome as compared to the pseudo-tetraploid xenopus laevis. amphibians undergo a biphasic development: embryogenesis to produce a free-living tadpoles and subsequent metamorphosis to transform the tadpole to a frog. this second phase mimics the so-ca ...201930353533
expression of the hormonal fgf co-receptor klotho beta in the xenopus laevis model.klotho beta (klb), a single-pass transmembrane protein, has been described as a co-receptor for endocrine fgfs, such as fgf15/19 and fgf21, to regulate critical metabolic processes in multiple organs and tissues in adult mice. however, its function during early embryonic development remains largely unknown. in this paper, we evaluated for the first time the expression of klb mrna during early development of xenopus laevis by rt-pcr and whole mount in situ hybridization. rt-pcr experiments showed ...201930259590
high-affinity k+ transporters from a halophyte, sporobolus virginicus, mediate both k+ and na+ transport in transgenic arabidopsis, x. laevis oocytes and yeast.class ii high-affinity potassium transporters (hkts) have been proposed to mediate na+-k+ co-transport in plants, as well as na+ and k+ homeostasis under k+-starved and saline environments. we identified class ii hkts, namely svhkt2;1 and svhkt2;2 (svhkts), from the halophytic turf grass, sporobolus virginicus. svhkt2;2 expression in s. virginicus was up-regulated by nacl treatment, while svhkt2;1 expression was assumed to be up-regulated by k+ starvation and down-regulated by nacl treatment. lo ...201930325438
generation and analysis of xenopus laevis models of retinal degeneration using crispr/cas9.xenopus laevis have proven to be a useful system for rapid generation and analysis of transgenic models of human retinal disease. however, experimental approaches in this system were limited by lack of a robust knockdown or knockout technology. here we describe a protocol for generation of cas9-edited x. laevis embryos. the technique introduces point mutations into the genome of x. laevis resulting in in-frame and out-of-frame insertions and deletions that allow modeling of both dominant and rec ...201930324446
design, synthesis, and pharmacological evaluation of novel β2/3 subunit-selective γ-aminobutyric acid type a (gabaa) receptor modulators.subunit-selective modulation of γ-aminobutyric acid type a receptors (gabaar) is considered to exert fewer side effects compared to unselective clinically used drugs. here, the β2/3 subunit-selective gabaar modulators valerenic acid (va) and loreclezole (lor) guided the synthesis of novel subunit-selective ligands with simplified structures. we studied their effects on gabaars expressed in xenopus laevis oocytes using two-microelectrode voltage clamp technique. five compounds showed significantl ...201930289721
lymphocyte deficiency induced by sublethal irradiation in xenopus.in many studies of diseases affecting amphibians, it is important to determine to what extent lymphocyte-mediated defenses are involved. for example, in studies of the nature of the immune response of xenopus laevis to the amphibian chytrid fungus, batrachochytrium dendrobatidis, it was essential to determine if mucosal antimicrobial peptides or lymphocyte-mediated immunity was most important for resistance to this skin pathogen. in this protocol, we describe a method for sublethal irradiation t ...201930104411
expression cloning human and rat renal cortex na/pi cotransporters: behind the scenes in the murer laboratory.in the pre-genomic era, the cloning of a cdna represented a significant achievement, particularly if the gene of interest encoded a membrane protein. at the time, molecular probes such as partial peptide sequences, suitable nucleic acid sequences, or antibodies were unavailable for most proteins and the "sodium-phosphate transporter" was no exception. in contrast, brush-border membrane vesicles and epithelial cell culture experiments had established a reliable set of functional hallmarks that de ...201930175377
mass spectrometry-based absolute quantification of single xenopus embryo proteomes.early xenopus development is characterized by a poor correlation between global mrna and protein abundances due to maternal mrna and protein loading. therefore, proteome profiling is necessary to study gene expression dynamics during early xenopus development. in contrast to mammals, single xenopus eggs and embryos contain enough protein to allow identification and quantification of thousands of proteins using mass spectrometry-based proteomics. in addition to investigating developmental process ...201930104410
regulation of melanopsin signaling: key interactions of the nonvisual photopigment.melanopsin is a g protein-coupled receptor with a peak sensitivity in the blue part of the spectrum, which plays a key role in nonvisual light-mediated signaling. recently, its importance in forming visual pathway as well as its role in blood vessels photorelaxation was also revealed. melanopsin was discovered in 1998 in xenopus leavis. since then, the melanopsin presence was demonstrated across the species. the existence of two melanopsin genes (opn4m and opn4x) as well as melanopsin isoforms r ...201930102761
assessing antibody responses to pathogens or model antigens in xenopus by enzyme-linked immunosorbent assay (elisa).xenopus laevis-specific monoclonal antibodies recognize igm and igy antibodies not only from x. laevis but also x. tropicalis as well as a variety of amphibian species including ranidae, bufonidae, and even some salamanders. these reagents are very useful to assess antibody responses from the serum or other animal secretions (e.g., peritoneal fluid). we present here an enzyme-linked immunosorbent assay (elisa) optimized for amphibians that permits users to detect and titrate the presence of each ...201930042135
copper uptake mechanism of arabidopsis thaliana high-affinity copt transporters.copper (cu) is an essential plant micronutrient. under scarcity, cu2+ is reduced to cu+ and taken up through specific high-affinity transporters (copts). in arabidopsis, the copt family consists of six members, either located at the plasma membrane (copt1, copt2, and copt6) or in internal membranes (copt3 and copt5). cu uptake by copt proteins has been mainly assessed through complementation studies in corresponding yeast mutants, but the mechanism of this transport has not been elucidated. to t ...201930043153
following endocrine-disrupting effects on gene expression in xenopus laevis.endocrine-disrupting chemicals (edcs), found in all categories of chemicals, are suspected to be a cause of declining well-being and human health, both as single molecules and as mixtures. it is therefore necessary to develop high throughput methods to assess the endocrine-disrupting potential of multiple chemicals currently on the market that are as yet untested. an advantage of in vivo chemical screening is that it provides a full spectrum of physiological impacts exerted by a given chemical. ...201930042138
bile acids inhibit human purinergic receptor p2x4 in a heterologous expression system.we recently demonstrated that bile acids, especially tauro-deoxycholic acid (t-dca), modify the function of the acid-sensing ion channel asic1a and other members of the epithelial sodium channel (enac)/degenerin (deg) ion channel family. surprisingly, asic1 shares a high degree of structural similarity with the purinergic receptor p2x4, a nonselective cation channel transiently activated by atp. p2x4 is abundantly expressed in the apical membrane of bile duct epithelial cells and is therefore ex ...201930988062
pacap-38 and pacap(6-38) degranulate rat meningeal mast cells via the orphan mrgb3-receptor.infusion of pituitary adenylate cyclase activating peptide-38 (pacap-38) provokes migraine attacks in migraineurs and headache in non-migraineurs. adverse events like long-lasting flushing and heat sensation can be terminated with oral antihistamine treatment, indicating the involvement of mast cell activation after pacap-infusion. degranulation of rat peritoneal mast cells was provoked by several isoforms of pacap via previously unknown receptor pharmacology. the effect might thus be mediated e ...201930983973
molecular markers for corneal epithelial cells in larval vs. adult xenopus frogs.corneal epithelial stem cells (cescs) and their proliferative progeny, the transit amplifying cells (tacs), are responsible for maintaining the integrity and transparency of the cornea. these stem cells (scs) are widely used in corneal transplants and ocular surface reconstruction. molecular markers are essential to identify, isolate and enrich for these cells, yet no definitive cesc marker has been established. an extensive literature survey shows variability in the expression of putative cesc ...201930981716
molecular and functional characterization of a short-type peptidoglycan recognition protein, pgrp-s in the amphibian xenopus laevis.peptidoglycan recognition proteins (pgrps) are a family of pattern recognition receptors (prrs) involved in host antibacterial responses, and their functions have been characterized in most invertebrate and vertebrate animals. however, little information is available regarding the function of frog pgrps. in this study, a short-type pgrp (termed xl-pgrp-s) gene was identified in the african clawed frog, xenopus laevis. the predicted protein of xl-pgrp-s contains several structural features known ...201930980872
autophagy in xenopus laevis rod photoreceptors is independently regulated by phototransduction and misfolded rhop23h.we previously reported autophagic structures in rod photoreceptors expressing a misfolding rho (rhodopsin) mutant (rhop23h), suggesting that autophagy may play a role in degrading the mutant rho and/or be involved in photoreceptor cell death. to further examine autophagy in normal and diseased rods, we generated transgenic xenopus laevis tadpoles expressing the dually fluorescent autophagy marker mrfp-egfp-lc3 in rods, which changes from green to yellow and finally red as autophagic structures d ...201930975014
optoelectronic control of single cells using organic photocapacitors.optical control of the electrophysiology of single cells can be a powerful tool for biomedical research and technology. here, we report organic electrolytic photocapacitors (oepcs), devices that function as extracellular capacitive electrodes for stimulating cells. oepcs consist of transparent conductor layers covered with a donor-acceptor bilayer of organic photoconductors. this device produces an open-circuit voltage in a physiological solution of 330 mv upon illumination using light in a tiss ...201930972364
thermal reduction of graphene oxide mitigates its in vivo genotoxicity toward xenopus laevis tadpoles.the worldwide increase of graphene family materials raises the question of the potential consequences resulting from their release in the environment and future consequences on ecosystem health, especially in the aquatic environment in which they are likely to accumulate. thus, there is a need to evaluate the biological and ecological risk but also to find innovative solutions leading to the production of safer materials. this work focuses on the evaluation of functional group-safety relationshi ...201930970633
n-glycosylation-dependent regulation of hk2p17.1 currents.two pore-domain potassium (k2p) channels mediate potassium background currents that stabilize the resting membrane potential and facilitate action potential repolarization. in the human heart, hk2p17.1 channels are predominantly expressed in the atria and purkinje cells. reduced atrial hk2p17.1 protein levels were described in patients with atrial fibrillation or heart failure. genetic alterations in hk2p17.1 were associated with cardiac conduction disorders. little is known about posttranslatio ...201930969900
modeling congenital kidney diseases in xenopus laevis.congenital anomalies of the kidney and urinary tract (cakut) occur in ∼1/500 live births and are a leading cause of pediatric kidney failure. with an average wait time of 3-5 years for a kidney transplant, the need is high for the development of new strategies aimed at reducing the incidence of cakut and preserving renal function. next-generation sequencing has uncovered a significant number of putative causal genes, but a simple and efficient model system to examine the function of cakut genes ...201930967415
critical role of an mhc class i-like/innate-like t cell immune surveillance system in host defense against ranavirus (frog virus 3) infection.besides the central role of classical major histocompatibility complex (mhc) class ia-restricted conventional cluster of differentiation 8 (cd8) t cells in antiviral host immune response, the amphibian xenopuslaevis critically rely on mhc class i-like (mhc1b10.1.l or xnc10)-restricted innate-like (i)t cells (ivα6 t cells) to control infection by the ranavirus frog virus 3 (fv3). to complement and extend our previous reverse genetic studies showing that ivα6 t cells are required for tadpole survi ...201930959883
is normalized hindlimb length measurement in assessment of thyroid disruption in the amphibian metamorphosis assay relevant?the amphibian metamorphosis assay represents an oecd level 3 and edsp tier 1 ecotoxicity test assessing thyroid activity of chemicals in african clawed frog (xenopus laevis). to evaluate the effectiveness of snout-vent length (svl) normalization of hindlimb length (hll), correlation between the hll and svl or body weight was evaluated in the control groups of 10 individual studies from three laboratories. two studies required separate analysis of the nieuwkoop-faber (nf) stage ≤60 and >60 animal ...201930957914
loss of function of kmt2d, a gene mutated in kabuki syndrome, affects heart development in xenopus laevis.kabuki syndrome is a haploinsufficient congenital multi-organ malformation syndrome, which frequently includes severe heart defects. mutations in the histone h3k4 methyltransferase kmt2d have been identified as the main cause of kabuki syndrome, however, the role of kmt2d in heart development remains to be characterized.201930980591
antimicrobial peptides of multicellular organisms: my perspective.antimicrobial peptides of multicellular organisms were first characterized in the 1980s by investigators who felt that known systems of immunity could not explain what they observed: the resistance to bacterial infection of a cecropia moth pupa lacking antibodies or lymphocytes (cecropins (steiner 1981)), the potent microbicidal activity of neutrophils from a rabbit (defensins (selsted et al. 1985)), and the healing of a wound on the skin of the african clawed frog without infection in a non-ste ...201930980349
mitotic replisome disassembly depends on traip ubiquitin ligase activity.we have shown previously that the process of replication machinery (replisome) disassembly at the termination of dna replication forks in the s-phase is driven through polyubiquitylation of one of the replicative helicase subunits (mcm7) by cul2lrr1 ubiquitin ligase. interestingly, upon inhibition of this pathway in caenorhabditis elegans embryos, the replisomes retained on chromatin were unloaded in the subsequent mitosis. here, we show that this mitotic replisome disassembly pathway exists in ...201930979826
evaluation of cyclic luciferin as a substrate for luminescence measurements in in vitro and in vivo applications.bioluminescence imaging (bli) is a powerful tool for cell tracking, monitoring of gene delivery and expression in small laboratory animals. an alternative luciferase (luc) substrate cyclic luciferin (cycluc) was recently advanced for bli applications as providing a stronger, more stable signal at significantly lower doses than the classical substrate d-luciferin (d-luc) increasing sensitivity of luc detection 10 to 100 times. we evaluated benefits of using cycluc in in vivo studies in mice injec ...201930979501
in vivo and in vitro quantitative analysis of neural crest cell migration.the neural crest is an embryonic cell population induced at the border of the neural plate from where it delaminates and migrates long distances across the embryo. due to its extraordinary migratory capabilities, the neural crest has become a powerful system to study cellular and molecular aspects of collective and single cell migration both in vivo and in vitro. here we provide detailed protocols used to perform quantitative analysis of molecular and cellular aspects of xenopus laevis neural cr ...201930977071
hybrid-type and two-tetrad antiparallel telomere dna g-quadruplex structures in living human cells.although the telomeric sequence has been reported to form various g-quadruplex topologies in vitro and in xenopus laevis oocytes, in living human cells, the topology of telomeric dna g-quadruplex remains a challenge. to investigate the human telomeric dna g-quadruplex in a more realistic human cell environment, in the present study, we demonstrated that the telomeric dna sequence can form two hybrid-type and two-tetrad antiparallel g-quadruplex structures by in-cell 19f nmr in living human cells ...201930976813
pyrophosphate stimulates the phosphate-sodium symporter of trypanosoma brucei acidocalcisomes and saccharomyces cerevisiae vacuoles.inorganic pyrophosphate (ppi) is a by-product of biosynthetic reactions and has bioenergetic and regulatory roles in a variety of cells. here we show that ppi and other pyrophosphate-containing compounds, including polyphosphate (polyp), can stimulate sodium-dependent depolarization of the membrane potential and pi conductance in xenopus oocytes expressing a saccharomyces cerevisiae or trypanosoma brucei na+/pi symporter. ppi is not taken up by xenopus oocytes, and deletion of the tbpho91 spx do ...201930944211
new roles for wnt and bmp signaling in neural anteroposterior patterning.during amphibian development, neural patterning occurs via a two-step process. spemann's organizer secretes bmp antagonists that induce anterior neural tissue. a subsequent caudalizing step re-specifies anterior fated cells to posterior fates such as hindbrain and spinal cord. the neural patterning paradigm suggests that a canonical wnt-signaling gradient acts along the anteroposterior axis to pattern the nervous system. wnt activity is highest in the posterior, inducing spinal cord, at intermed ...201930936121
microsampling capillary electrophoresis mass spectrometry enables single-cell proteomics in complex tissues: developing cell clones in live xenopus laevis and zebrafish embryos.label-free single-cell proteomics by mass spectrometry (ms) is currently incompatible with complex tissues without requiring cell culturing, single-cell dissection, or tissue dissociation. we here report the first example of label-free single-cell ms-based proteomics directly in single cells in live vertebrate embryos. our approach integrates optically guided in situ subcellular capillary microsampling, one-pot extraction-digestion of the collected proteins, peptide separation by capillary elect ...201930827088
the c-terminus of the retinal homeobox (rax) gene product modulates transcription in a context-dependent manner.the evolutionarily conserved retinal homeobox (rax) transcription factor is essential for normal eye development in all vertebrates. despite rax's biologic significance, the molecular mechanisms underlying rax molecular function as a transcriptional regulator are poorly defined. the rax gene encodes a conserved octapeptide motif (op) near the n-terminus and several conserved regions in the c-terminus of unknown function, including the orthopedia, aristaless, rax (oar) domain and the rx domain. t ...201930820152
conditional demyelination and remyelination in a transgenic xenopus laevis.multiple sclerosis (ms) is the first cause of acquired disability progression in the young adult. pathology of ms associates inflammation, demyelination, and neurodegeneration. the development of immunotherapies, by reducing the relapse rate, has profoundly impacted short-term prognosis and patients' quality of life. these anti-inflammatory medications, however, have not proven to be sufficient to prevent long-term disability progression, resulting from axonal transection and neuronal damage, co ...201930820903
latrophilin2 is involved in neural crest cell migration and placode patterning in xenopus laevis.latrophilin2 (lphn2) is an adhesion-class of g protein-coupled receptor with an unknown function in development. here, we show that xenopus laevis lphn2 (xlphn2) is involved in the migration and differentiation of neural crest (nc) cells and placode patterning in xenopus laevis embryos. although xlphn2 mrna was detected throughout embryogenesis, it was expressed more abundantly in the placode region. morpholino antisense oligonucleotide-mediated knockdown of xlphn2 caused abnormal migration of n ...201930919913
regulation of na+-k+-cl- cotransporter type 2 by the with no lysine kinase-dependent signaling pathway.na+-k+-cl- cotransporter type 2 (nkcc2) is confined to the apical membrane of the thick ascending limb of henle, where it reabsorbs a substantial fraction of the ultrafiltered nacl load. it is expressed along this nephron segment as three main splice variants (called nkcc2a, nkcc2b, and nkcc2f) that differ in residue composition along their second transmembrane domain and first intracellular cytosolic connecting segment (cs2). nkcc2 is known to be activated by cell shrinkage and intracellular [c ...201930917032
agr2-interacting prod1-like protein tfp4 from xenopus laevis is necessary for early forebrain and eye development as well as for the tadpole appendage regeneration.the agr family genes, ag1, agr2, and agr3, encode for the thioredoxin domain containing secreted proteins and are specific only for vertebrates. these proteins are attracting increasing attention due to their involvement in many physiological and pathological processes, including exocrine secretion, cancer, regeneration of the body appendages, and the early brain development. at the same time, the mode by which agrs regulate intracellular processes are poorly understood. despite that the recepto ...201930912273
xmap215 promotes microtubule-f-actin interactions to regulate growth cone microtubules during axon guidance in xenopuslaevis.it has long been established that neuronal growth cone navigation depends on changes in microtubule (mt) and f-actin architecture downstream of guidance cues. however, the mechanisms by which mts and f-actin are dually coordinated remain a fundamentally unresolved question. here, we report that the well-characterized mt polymerase, xmap215 (also known as ckap5), plays an important role in mediating mt-f-actin interaction within the growth cone. we demonstrate that xmap215 regulates mt-f-actin al ...201930890650
mechanical force induces phosphorylation-mediated signaling that underlies tissue response and robustness in xenopus embryos.mechanical forces are essential drivers of numerous biological processes, notably during development. although it is well recognized that cells sense and adapt to mechanical forces, the signal transduction pathways that underlie mechanosensing have remained elusive. here, we investigate the impact of mechanical centrifugation force on phosphorylation-mediated signaling in xenopus embryos. by monitoring temporal phosphoproteome and proteome alterations in response to force, we discover and valida ...201930852251
a unique role of thyroid hormone receptor β in regulating notochord resorption during xenopus metamorphosis.tail resorption during anuran metamorphosis is perhaps the most dramatic tissue transformation that occurs during vertebrate development. earlier studies in highly related anuran species xenopus laevis and xenopus tropicalis have shown that thyroid hormone (t3) receptor (tr) plays a necessary and sufficient role to mediate the causative effect of t3 on metamorphosis. of the two known tr genes in vertebrates, trα is highly expressed during both premetamorphosis and metamorphosis while trβ express ...201930851299
distinctive single-channel properties of α4β2-nicotinic acetylcholine receptor isoforms.central nervous system nicotinic acetylcholine receptors (nachr) are predominantly of the α4β2 subtype. two isoforms exist, with high or low agonist sensitivity (hs-(α4β2)2β2- and ls-(α4β2)2α4-nachr). both isoforms exhibit similar macroscopic potency and efficacy values at low acetylcholine (ach) concentrations, mediated by a common pair of high-affinity α4(+)/(-)β2 subunit binding interfaces. however ls-(α4β2)2α4-nachr also respond to higher concentrations of ach, acting at a third α4(+)/(-)α4 ...201930845161
evolution of the rho guanine nucleotide exchange factors kalirin and trio and their gene expression in xenopus development.guanine nucleotide exchange factors (gefs) activate rho gtpases by accelerating their gdp/gtp exchange. trio and its paralog kalirin (kalrn) are unique members of the rho-gefs that harbor three catalytic domains: two functional gef domains and a serine/threonine kinase domain. the n-terminal gef domain activates rac1 and rhog gtpases, while the c-terminal gef domain acts specifically on rhoa. trio and kalrn have an evolutionary conserved function in morphogenetic processes including neuronal dev ...201930844509
electrophysiological changes during early steps of retinitis pigmentosa.the rhodopsin mutation p23h is responsible for a significant portion of autosomal-dominant retinitis pigmentosa, a disorder characterized by rod photoreceptor death. the mechanisms of toxicity remain unclear; previous studies implicate destabilization of p23h rhodopsin during light exposure, causing decreased endoplasmic reticulum (er) exit and er stress responses. here, we probed phototransduction in xenopus laevis rods expressing bovine p23h rhodopsin, in which retinal degeneration is inducibl ...201930840038
menthol acts as a positive allosteric modulator on nematode levamisole sensitive nicotinic acetylcholine receptors.the ongoing and widespread emergence of resistance to the existing anti-nematodal pharmacopeia has made it imperative to develop new anthelminthic agents. historically, plants have been important sources of therapeutic compounds and offer an alternative to synthetic drugs. monoterpenoids are phytochemicals that have been shown to produce acute toxic effects in insects and nematodes. previous studies have shown nicotinic acetylcholine receptors (nachrs) to be possible targets for naturally occurr ...201930682641
fluorescent analogues of bekm-1 with high and specific activity against the herg channel.peptidic toxins that target specifically mammalian channels and receptors can be found in the venom of animals. these toxins are rarely used directly as tools for biochemical experiments, and need to be modified via the attachment of chemical groups (e.g., radioactive or fluorescent moieties). ideally, such modifications should maintain the toxin specificity and affinity for its target. with the goal of obtaining fluorescent derivatives of bekm-1, a toxin from the scorpion species buthus eupeus ...201932550567
characterization of xenopus laevis guanine deaminase reveals new insights for its expression and function in the embryonic kidney.the mammalian guanine deaminase (gda), called cypin, is important for proper neural development, by regulating dendritic arborization through modulation of microtubule (mt) dynamics. additionally, cypin can promote mt assembly in vitro. however, it has never been tested whether cypin (or other gda orthologs) binds to mts or modulates mt dynamics. here, we address these questions and characterize xenopus laevis gda (gda) for the first time during embryonic development.201930682232
comparison the sensitivity of amphibian metamorphosis assays with nf 48 stage and nf 51 stage xenopus laevis tadpoles.the amphibian metamorphosis assay (ama) was proposed by the organization for economic cooperation and development (oecd) to screen thyroid disruptors of vertebrate species. the general experimental design of the ama exposes nieuwkoop and faber (nf) stage 51 xenopus laevis tadpoles to test chemical concentrations for 21 d. however, recent studies demonstrated that thyroid gland began to function after nf stage 45 in x. laevis. thus, in this study, we initiated exposure with nf stage 48 tadpoles w ...201930732517
oscillating aquaporin phosphorylation and 14-3-3 proteins mediate the circadian regulation of leaf hydraulics.the circadian clock regulates plant tissue hydraulics to synchronize water supply with environmental cycles and thereby optimize growth. the circadian fluctuations in aquaporin transcript abundance suggest that aquaporin water channels play a role in these processes. here, we show that hydraulic conductivity (kros) of arabidopsis (arabidopsis thaliana) rosettes displays a genuine circadian rhythmicity with a peak around midday. combined immunological and proteomic approaches revealed that phosph ...201930674691
non-acylated wnts can promote signaling.wnts are a family of 19 extracellular ligands that regulate cell fate, proliferation, and migration during metazoan embryogenesis and throughout adulthood. wnts are acylated post-translationally at a conserved serine and bind the extracellular cysteine-rich domain (crd) of frizzled (fzd) seven-pass transmembrane receptors. although crystal structures suggest that acylation is essential for wnt binding to fzds, we show here that several wnts can promote signaling in xenopus laevis and danio rerio ...201930673610
analysis of long non-coding rna involved in atrazine-induced testicular degeneration of xenopus laevis.long non-coding rna (lncrna) plays a critical role in male germline development. atrazine (az) as an environmental endocrine disrupting chemical (edcs) can induce male reproductive toxicity in amphibians. our previous studies demonstrated that az can alter gene and circular rna (circrna) expression of damaged testes in xenopus laevis (x. laevis). we furthered to investigate the lncrna expression profiling in the testis of x. laevis. over 3559 lncrnas were detected by lncrna sequencing. az induce ...201930675760
effect of the flavonoid hesperidin on glucose and fructose transport, sucrase activity and glycaemic response to orange juice in a crossover trial on healthy volunteers.although polyphenols inhibit glucose absorption and transport in vitro, it is uncertain whether this activity is sufficient to attenuate glycaemic response in vivo. we examined this using orange juice, which contains high levels of hesperidin. we first used a combination of in vitro assays to evaluate the potential effect of hesperidin and other orange juice components on intestinal sugar absorption and then tested whether this translated to an effect in healthy volunteers. hesperidin attenuated ...201930670104
whole-cell photoacoustic sensor based on pigment relocalization.photoacoustic (optoacoustic) imaging can extract molecular information with deeper tissue penetration than possible by fluorescence microscopy techniques. however, there is currently still a lack of robust genetically controlled contrast agents and molecular sensors that can dynamically detect biological analytes of interest with photoacoustics. in a biomimetic approach, we took inspiration from cuttlefish who can change their color by relocalizing pigment-filled organelles in so-called chromato ...201930663315
x-linked α-thalassemia with mental retardation is downstream of protein kinase a in the meiotic cell cycle signaling cascade in xenopus oocytes and is dynamically regulated in response to dna damage†.x-linked α-thalassemia with mental retardation (atrx) is a chromatin remodeling protein that belongs to the switch/sucrose non-fermentable (swi2/snf2) family of helicase/atpases. during meiosis, atrx is necessary for heterochromatin formation and maintenance of chromosome stability in order to ensure proper assembly of the metaphase ii spindle. previously, we established atrx as a novel progesterone regulated protein during bovine meiotic maturation, in addition to being dynamically regulated in ...201930649195
the electrical block to polyspermy induced by an intracellular ca2+ increase at fertilization of the clawed frogs, xenopus laevis and xenopus tropicalis.polyspermy blocking, to ensure monospermic fertilization, is necessary for normal diploid development in most animals. we have demonstrated here that monospermy in the clawed frog, xenopus tropicalis, as well as in x. laevis, is ensured by a fast, electrical block to polyspermy on the egg plasma membrane after the entry of the first sperm, which is mediated by the positive-going fertilization potential. an intracellular ca2+ concentration ([ca2+ ]i ) at the sperm entry site was propagated as a c ...201930648313
rho flares repair local tight junction leaks.tight junctions contribute to epithelial barrier function by selectively regulating the quantity and type of molecules that cross the paracellular barrier. experimental approaches to evaluate the effectiveness of tight junctions are typically global, tissue-scale measures. here, we introduce zinc-based ultrasensitive microscopic barrier assay (znumba), which we used in xenopus laevis embryos to visualize short-lived, local breaches in epithelial barrier function. these breaches, or leaks, occur ...201930773490
activity and intracellular localization of senescence-associated β-galactosidase in aging xenopus oocytes and eggs.senescence-associated β-galactosidase (sa-β-gal) serves as a marker of senescence in aging somatic cells. however, little is known about sa-β-gal dynamics in aging gamete cells. to address this issue, here we investigated activity and intracellular localization of sa-β-gal in freshly obtained and aging oocytes and eggs of the african clawed frog xenopus laevis. data base mining revealed the presence of several homologous β-galactosidase sequences in the annotated xenopus genome. some of them wer ...201930769028
xenopus oocytes as a heterologous expression system for analysis of tight junction proteins.claudins (cldns) represent the largest family of transmembrane tight junction (tj) proteins, determining organ-specific epithelial barrier properties. because methods for the analysis of multiple cldn interaction are limited, we have established the heterologous xenopus laevis oocyte expression system for tj protein assembly and interaction analysis. oocytes were injected with crna encoding human cldn-1, -2, or -3 or with a combination of these and were incubated in pairs for interaction analysi ...201930645152
insemination or phosphatidic acid induces an outwardly spiraling disk of elevated ca2+ to produce the ca2+ wave during xenopus laevis fertilization.during xenopus fertilization, the initial intracellular calcium ((ca2+)i) release at the sperm-egg binding site (hot spot) has not been described without the use of inhibitors, nor related to underlying er structure. without inhibitors, we now report that sperm induce an initial hot spot after sperm addition to xenopus eggs that was ~25 µm. this area is consistent with the size of er patches and clusters of ip3 receptors that have enhanced activity. furthermore, we find a new mechanism for the f ...201930641042
on the mechanism of the electrophysiological changes and membrane lesions induced by asbestos fiber exposure in xenopus laevis oocytes.the so-called amphibole asbestos fibers are enriched with mineral iron ions, able to stimulate ros production. we recently reported that crocidolite asbestos was able to interact with the cell membranes of xenopus laevis oocytes, to alter their electrical membrane properties. here, we found that applied iron ions (fe3+) or h2o2 (for ros generation) mimicked these effects, suggesting that at least one effect of iron-containing asbestos fiber exposure was mediated by ros production. furthermore, c ...201930765791
wgddetector: a pipeline for detecting whole genome duplication events using the genome or transcriptome annotations.with the availability of well-assembled genomes of a growing number of organisms, identifying the bioinformatic basis of whole genome duplication (wgd) is a growing field of genomics. the most extant software for detecting footprints of wgds has been restricted to a well-assembled genome. however, the massive poor quality genomes and the more accessible transcriptomes have been largely ignored, and in theoretically they are also likely to contribute to detect wgd using ds based method. here, to ...201930760221
reinterpretation of the substrate specificity of the voltage-sensing phosphatase during dimerization.voltage-sensing phosphatases (vsps) cleave both 3- and 5-phosphates from inositol phospholipids in response to membrane depolarization. when low concentrations of ciona intestinalis vsp are expressed in xenopus laevis oocytes, the 5-phosphatase reaction can be observed during large membrane depolarizations. when higher concentrations are expressed, the 5-phosphatase activity is observed with smaller depolarizations, and the 3-phosphatase activity is revealed with strong depolarization. here we a ...201930622132
ensa and arpp19 differentially control cell cycle progression and development.greatwall (gwl) is an essential kinase that indirectly controls pp2a-b55, the phosphatase counterbalancing cyclin b/cdk1 activity during mitosis. in xenopus laevis egg extracts, gwl-mediated phosphorylation of overexpressed arpp19 and ensa turns them into potent pp2a-b55 inhibitors. it has been shown that the gwl/ensa/pp2a-b55 axis contributes to the control of dna replication, but little is known about the role of arpp19 in cell division. by using conditional knockout mouse models, we investiga ...201930626720
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