| threonine 67 is a key component in the coupling of the nss amino acid transporter kaat1. | | 2018 | 29409909 |
| molecular cloning, spatiotemporal and functional expression of gaba receptor subunits rdl1 and rdl2 of the rice stem borer chilo suppressalis. | insect γ-aminobutyric acid (gaba) receptor (gabar) is one of the major targets of insecticides. in the present study, cdnas (csrdl1a and csrdl2s) encoding the two isoforms of rdl subunits were cloned from the rice stem borer chilo suppressalis. transcripts of both genes demonstrated similar expression patterns in different tissues and developmental stages, although csrdl2s was ∼2-fold more abundant than csrdl1a throughout all development stages. to investigate the function of channels formed by ... | 2018 | 29408355 |
| tooth germ initiation patterns in a developing dentition: an in vivo study of xenopus laevis tadpoles. | the transparency of soft tissue in xenopus laevis tadpoles and the anterior-posterior orientation of their developing tooth germs in the upper jaw offer a unique opportunity for the in vivo charting of the first 15-20 days of the developing dentition. twenty-two x. laevis tadpoles were anesthetized daily and their mouths opened to record the first appearance, position, and development of tooth germs in the upper jaw. the initiation patterns revealed considerable variability between animals, and ... | 2018 | 29399866 |
| the phosphorylation site t613 in the β-subunit of rat epithelial na+ channel (enac) modulates channel inhibition by nedd4-2. | the epithelial na+ channel (enac) is a heteromeric channel composed of three subunits (α, β, γ). at the c-terminus of each subunit, a py-motif allows binding of the ubiquitin ligase nedd4-2 which plays a key role in promoting enac retrieval from the plasma membrane. phosphorylation of nedd4-2 by the serum and glucocorticoid-inducible kinase 1 (sgk1) reduces nedd4-2 binding to the py-motifs. in β and γenac, threonine residues (βt613, γt623) belong to an extracellular signal-regulated kinase (erk) ... | 2018 | 29397423 |
| a multichannel computer-driven system to raise aquatic embryos under selectable hypoxic conditions. | the formation of a functional cardiovascular system is an essential step in the early vertebrate embryo. nevertheless, the effect of hypoxia on the developmental program of organisms was studied rarely. in particular, this holds true for vertebrate embryos that depend on a functional placenta for proper development and had not been studied in this respect due to the obvious limitation. we established a protocol to culture aquatic embryos, which enabled us to culture a high number of xenopus embr ... | 2018 | 29392150 |
| stac3 enhances expression of human cav1.1 in xenopus oocytes and reveals gating pore currents in hypopp mutant channels. | mutations of cav1.1, the pore-forming subunit of the l-type ca2+ channel in skeletal muscle, are an established cause of hypokalemic periodic paralysis (hypopp). however, functional assessment of hypopp mutant channels has been hampered by difficulties in achieving sufficient plasma membrane expression in cells that are not of muscle origin. in this study, we show that coexpression of stac3 dramatically increases the expression of human cav1.1 (plus α2-δ1b and β1a subunits) at the plasma membran ... | 2018 | 29386226 |
| protein immunodepletion and complementation in xenopus laevis egg extracts. | the xenopus egg extract system has been widely used to study cell cycle events, including dna replication, nuclear envelope formation, spindle assembly, chromosome condensation and kinetochore formation. the functional roles of the proteins involved in these processes can be determined by immunodepleting a protein of interest from the extract. as immunodepletion may result in co-depletion of other proteins, the protein of interest can be added back to the extract to verify its function. addition ... | 2018 | 29382808 |
| quantitative proteomics after spinal cord injury (sci) in a regenerative and a nonregenerative stage in the frog xenopus laevis. | the capacity to regenerate the spinal cord after an injury is a coveted trait that only a limited group of nonmammalian organisms can achieve. in xenopus laevis, this capacity is only present during larval or tadpole stages, but is absent during postmetamorphic frog stages. this provides an excellent model for comparative studies between a regenerative and a nonregenerative stage to identify the cellular and molecular mechanisms that explain this difference in regenerative potential. here, we us ... | 2018 | 29358338 |
| a model for investigating developmental eye repair in xenopus laevis. | vertebrate eye development is complex and requires early interactions between neuroectoderm and surface ectoderm during embryogenesis. in the african clawed frog, xenopus laevis, individual eye tissues such as the retina and lens can undergo regeneration. however, it has been reported that removal of either the specified eye field at the neurula stage or the eye during tadpole stage does not induce replacement. here we describe a model for investigating xenopus developmental eye repair. we found ... | 2018 | 29357285 |
| molecular characterization and tissue expression profiles of prepro-vasoactive intestinal peptide in the chinese alligator (alligator sinensis) during the active and hibernating periods. | the chinese alligator (alligator sinensis), a freshwater crocodilian endemic to china, is one of the most endangered crocodilian species; up to this date, very little is known about the endocrine regulation of its metabolic activities during different physiological states. in this study, we characterized the structure of the prepro-vasoactive intestinal peptide in chinese alligator (prepro-cavip) for the first time and examined its expression profiles in various tissues during the active and hib ... | 2017 | 29356375 |
| micrornas associated with early neural crest development in xenopus laevis. | the neural crest (nc) is a class of transitory stem cell-like cells unique to vertebrate embryos. nc cells arise within the dorsal neural tube where they undergo an epithelial to mesenchymal transition in order to migrate and differentiate throughout the developing embryo. the derivative cell types give rise to multiple tissues, including the craniofacial skeleton, peripheral nervous system and skin pigment cells. several well-studied gene regulatory networks underpin nc development, which when ... | 2018 | 29347911 |
| invasive american bullfrogs and african clawed frogs in south america: high suitability of occurrence in biodiversity hotspots. | fabiana g. barbosa, camila both, and miguel b. araújo (2017) invasion of protected areas by non-native species is currently one of the main threats to global biodiversity. using an ensemble of bioclimatic envelope models we quantify the degree of exposure of south american protected areas to invasion by two invasive amphibian species. we focus on protected areas that coincide with global biodiversity hotspots. the species modeled, lithobates catesbeianus and xenopus laevis, have been reported to ... | 2017 | 31966227 |
| [morphomechanical factors in gastrulation process and differentiation of embryonic tissue of xenopus laevis]. | effect of mechanical stretch on the differentiation of axial anlages and chordin gene expressionwas studied in sandwich explants prepared from embryonic tissues of xenopus laevis at the early gastrula stagein two variants: with dissected or intact dorso-medial region. in the first case, convergent cell movementswere suppressed and properly organized axial organs (notochord and somites) were almost completely absent.however, they developed if the explants of such type were artificially stretched ... | 2018 | 30272924 |
| [role of mechano-dependent cell movements in the establishment of spatial organization of axial rudiments in xenopus laevis embryos]. | trajectories of individual cell movements and patterns of differentiation in the axial rudiments insuprablastoporal areas (sba) in whole embryos of xenopus laevis artificially stretched in the transverse directionup to 120–200% from the initial length at the early gastrula stage were mapped. we observed the impairmentof anisotropic cell movements of longitudinal stretching and latero-medial convergence inherent forsba. axial rudiments occurred in all cases, but their location was completely impa ... | 2018 | 30272919 |
| biometric data assessment on xenopus laeis tadpoles. | | 2016 | 30701053 |
| structural heterogeneity of cnga1 channels revealed by electrophysiology and single-molecule force spectroscopy. | the determination at atomic resolution of the three-dimensional molecular structure of membrane proteins such as receptors and several ion channels has been a major breakthrough in structural biology. the molecular structure of several members of the superfamily of voltage-gated ionic channels such as k+ and na+ is now available. however, despite several attempts, the molecular structure at atomic resolution of the full cyclic nucleotide-gated (cng) ion channel, although a member of the same sup ... | 2016 | 31457189 |
| [geometry of movement of the outer surface of the embryo during xenopus gastrulation]. | the surface of xenopus laevis embryos was marked with carbon particles, after which the locationof mark groups was recorded by time-lapse video imaging and subsequent image analysis until their disappearancein the depth of gastric invagination. measuring the distances between individually identifiablemarks whose size is smaller than the size of a single cell makes it possible to quantitatively analyze the geometryof collective cell movement without any external coordinate system. during the dors ... | 2018 | 30272406 |
| [secreted protein noggin4 participates in the formation of forebrain structures in xenopus laevis by inhibitingthe wnt/beta-catenin signaling pathway]. | noggin proteins are important regulators of the early development of the vertebrate neural system.previously, it has been traditionally thought that vertebrates have only one noggin gene (noggin1), whosemain function is the inhibition of bmp signaling pathway during the formation of dorsoventral polarity inembryos. then other proteins of this family were discovered, and the studies of noggin2 protein showed thatnoggin proteins also participate in the modulation of nodal/activin and wnt/beta-cate ... | 2018 | 30272399 |
| a matter of the heart: the african clawed frog xenopus as a model for studying vertebrate cardiogenesis and congenital heart defects. | the african clawed frog, xenopus, is a valuable non-mammalian model organism to investigate vertebrate heart development and to explore the underlying molecular mechanisms of human congenital heart defects (chds). in this review, we outline the similarities between xenopus and mammalian cardiogenesis, and provide an overview of well-studied cardiac genes in xenopus, which have been associated with congenital heart conditions. additionally, we highlight advantages of modeling candidate genes deri ... | 2016 | 29367567 |
| effect of ginsenosides on the desflurane modulation in the recombinant serotonin type 3a receptor expressed in xenopus laevis oocytes. | postoperative nausea and vomiting (ponv) is the most frequent and discomforting side effect following general anesthesia. most volatile anesthetics have a potent effect on serotonin (5-hydroxydtryptamine, 5-ht) type 3 receptor mediating ponv, and their antagonists have been currently used effectively to prevent and/or reduce the incidence and severity of ponv. the authors reported previously that ginsenosides have inhibitory effect on 5-ht3a receptor. in this study we intended to elucidate the i ... | 2009 | 30625810 |
| amino acid residues involved in agonist binding and its linking to channel gating, proximal to transmembrane domain of 5-ht3a receptor for halothane modulation. | the 5-hydroxytryptamine type 3 (5-ht3) receptor is a member of the cys-loop superfamily of ligand-gated ion channels (lgics) and modulated by pharmacologic relevant concentrations of volatile anesthetics or n-alcohols like most receptors of lgics. the goal of this study was to reveal whether the site-directed single mutations of e-106, f-107 and r-222 in 5-ht3 receptor may affect the anesthetic modulation of halothane known as positive modulator. | 2009 | 30625697 |
| comparative toxicity of ammonium and nitrate compounds to pacific treefrog and african clawed frog tadpoles. | the effects of ammonium nitrate, ammonium chloride, ammonium sulfate, and sodium nitrate on survival and growth of pacific treefrog (pseudacris regilla [baird and girard]) and african clawed frog (xenopus laevis [daudin]) tadpoles were determined in static-renewal tests. the 10-d ammonium nitrate and ammonium sulfate lc50s for p. regilla were 55.2 and 89.7 mg/l nh4 -n, respectively. the 10-d lc50s for x. laevis for the three ammonium compounds ranged from 45 to 64 μg/l nh4 - n. the 10-d sodium n ... | 1999 | 29857645 |
| progress toward identifying causes of maldevelopment induced in xenopus by pond water and sediment extracts from minnesota, usa. | in previously conducted laboratory studies with the south african clawed frog (xenopus laevis), pond water and sediment samples collected from various sites in minnesota, usa, were demonstrated to have the potential to induce a variety of developmental abnormalities, including early embryo-larval maldevelopment, abnormal limb development, and disruption of metamorphosis. the results of exposure of x. laevis to suspect pond water and sediment samples supported the hypothesis that these samples we ... | 1999 | 29857636 |
| testicular and androgen dependence of skin gland morphology in the anurans, xenopus laevis and rana pipiens. | in anuran amphibians, there is increasing evidence that exocrine glands dispersed throughout the general integument are secondary sex characters (ssc). following the recent discovery of sexually dimorphic "breeding glands" in the dorsum of male rana pipiens, we studied the effects of castration and testosterone treatment on the dorsal skin glands of male xenopus laevis and r. pipiens to determine whether the dorsal breeding glands, or any other dorsal skin glands, are androgen dependent. the dor ... | 1993 | 29865448 |
| development of the ethmoidal structures of the endocranium in the anuran pipa pipa. | investigation of eight developmental stages by means of serial sections and subsequent graphic or wax model reconstructions, as well as by means of cleared-and-stained and dissected material, revealed that the ethmoidal endocranium in pipa pipa consists in early states of a single horizontal ethmoid plate lacking labial cartilages. later in the course of development, structures comparable with those in other anurans appear, though modified and of reduced size. these adult structures arise from t ... | 1989 | 29865644 |
| ultrastructural changes in the connective tissue of the gastric region during the metamorphosis of xenopus laevis. | development of the gastric connective tissue of xenopus laevis during metamorphosis was investigated by electron microscopy. throughout the larval period to stage 60, the layer of connective tissue underlying the gastric epithelium consists of immature fibroblasts surrounded by a sparse extracellular matrix. at the beginning of the transition from the larval to the adult epithelial form, at about stage 60, extensive changes occur in the connective tissue. the number of cells suddenly increses an ... | 1989 | 29865622 |
| regenerative response of amputated forelimbs of xenopus laevis froglets to partial denervation. | xenopus laevis froglet forelimbs normally respond to amputational injury by forming a heteromorphic cartilaginous rod-shaped outgrowth. however, partial denervation of a forelimb by ablation of the n. radialis or the n. ulnaris, followed in 2 days by amputation through the mid radius-ulna, results in a size deficiency of the regenerative outgrowth 14 and 21 days postamputation. the decreasing quantity of forelimb innervation, as a result of partial denervation by 55 or 45%, apparently has a grad ... | 1987 | 29921109 |
| fine structure of oviducal epithelium of xenopus laevis in relation to its role in secreting egg envelopes. | during passage through the oviduct, the egg of xenopus laevis acquires the following substances or envelopes: electron-dense particles in the vitelline coat, the prefertilization layer in and around the vitelline coat, and four layers of jelly. both gross anatomical observation and light and scanning or transmission electron microscopic observations of various levels of oviduct revealed that the first two are produced in the pars recta 1 and 2 portions, and that jelly layers 1-4 are added in the ... | 1985 | 29976012 |
| fiber type composition and postmetamorphic growth of anuran hindlimb muscles. | fiber type composition distinguished by the level of succinic dehydrogenase, mean fiber diameter, and fiber number were determined for the gracilis major and sartorius in ontogenetic series of the anurans rana pipiens, bufo americanus, and xenopus laevis to characterize muscle composition and mode of muscle growth. a correlation can be made between the respective locomotor mode of these anurans, their activity physiology, and the fiber type composition of the propulsive muscles. r. pipiens and x ... | 1981 | 30119589 |
| development of the urostyle during metamorphosis in five species of anurans. | normal development of the urostyle is described during late stages of metamorphosis in five species of anurans: xenopus laevis (daudin), bufo americanus holbrook, pseudacris triseriata (wied), hyla chrysoscelis cope, and rana pipiens schreber. the developing urostyle of all five species is composed of essentially the same cartilaginous elements: one pair of basidorsals above the notochord and the subtended hypochord. among the five species there is variation in such details as the number of spin ... | 1979 | 30200677 |
| time-lapse cinemicrographic analysis of superficial cell behavior during and prior to gastrulation in xenopus laevis. | time-lapse cinemicrography was used to show what changes in the number, size, shape, arrangement and what movements of apices of superficial cells occur during epiboly, extension, convergence and blastopore formation in the blastula or gastrula of xenopus laevis. epiboly of the animal region occurs by apical expansion of superficial cells at a nearly constant rate from the midblastula to the midgastrula stage. egression of deep cells into the superficial layer does not occur. extension of the do ... | 1978 | 30235909 |
| xenopus laevis. | | 1949 | 18210578 |
| some improvements in the keeping and rearing of xenopus laevis. | | 1949 | 18124543 |
| hormonal studies in xenopus laevis daudin. | | 1949 | 18124957 |
| report on breeding success with xenopus laevis daudin. | | 1948 | 18885271 |
| diagnosis of pregnancy in the xenopus laevis frog. | | 1948 | 18894470 |
| breeding success in xenopus laevis daudin. | | 1948 | 18916776 |
| possible use of the batracian xenopus laevis in the control of mosquito larvae; various interactions to be expected. | | 1945 | 21015076 |