In line with the latter finding is the fact that Zn2+ (as ZnSO4) was also an effective agent mimicking progesterone action (unpublished) and indeed it was shown to inhibit adenylate cyclase in other systems(16). They are described to displace calcium from membrane sites, to inhibit CaATPase or to regulate the activity of adenylate cyclase (4,17). Xenopus laevis oocytes represent another heterologous system in which YSL transporter functionality has been studied. Agents interacting with meiosis in Xenopus laevis oocytes, Some steroids: progesterone, cortisol, testosterone, pregnenolone, Some organo-mercurials: parachloromercuribenzoate, mersalyl, Some ions: lanthanum, zinc, calcium*† magnesium*, Some antiarrythmic drugs: D-600(isoptin), D-200(verapamil), Some O-receptor adrenergic antagonists: isomers of propranolol, alprenolol, dichloroisoproterenol, Some local anesthetics: dibucaine, tetracaine, Some CNS acting drugs: barbital, imipramine, chlorpromazine, fluphenazine, fenfluramine, cycloheximide (inhibitor of protein synthesis), theophylline, IBMX (inhibitors of phosphodiesterases), dithiothreitol (protecting agent for SH groups), gammexane (inhibitor of phospholipid metabolism). (2001) Isotonic transport by the Na, Broer, S., Schneider, H. P., Broer, A., et al. (1984) Expression of functional acetylcholine receptor from cloned cDNAs. Dev Biol 36:669- cleavage furrow formation in Xenopus laevis oocytes and eggs. Cells to be avoided include those with diffuse lightening at the tip of the animal pole. Activity assays can be performed using isolated egg envelopes and SDS-PAGE to detect the gp43 to gp41 shift. After oocyte maturation, clear white spots appear at the top of animal hemispheres and follicle cells are peeled off. Most generally, it is very interesting to note that the parasites harbored by X. tropicalis and X. epitropicalis differ from those found in association with other Xenopus species (Tinsley and Jackson, 1998). This process is experimental and the keywords may be updated as the learning algorithm improves. Active liquid-like behavior of nucleoli determines their size and shape in Xenopus laevis oocytes Clifford P. Brangwynne , Timothy J. Mitchison , Anthony A. Hyman Proceedings of the National Academy of Sciences Mar 2011, 108 (11) 4334-4339; DOI: 10.1073/pnas.1017150108 Activity in Xenopus laevis Oocytes. Immature eggs (oocytes) of the South African clawed frog Xenopus laevis are considered an ideal expression system for such studies. Xenopus oocytes are widely used for heterologous expression of cRNAs encoding cytosolic enzymes, immunoglobulins, membrane receptors, ion channels, ion pumps, and membrane transporters. GeneClamp 500 amplifier, Digidata 1322A, and pCLAMP ver. This helps to avoid overdigestion and, often, many of the nondenuded cells will become defolliculated later as the sack of follicle cells sticks to the bottom of the culture dish. The incision is sutured with surgical silk and the frog is placed in shallow water in a small tank to allow it to recover from anesthesia before placing it in a special tank for postoperative frogs. Xenopus laevis Oocytes. pp 245-257 | Function i. In Xenopus laevis, vitellogenin (the yolk precursor) is synthesized in the liver and transported via the circulatory system to the ovary. Preparation. Poly(A)+ RNA was functionally expressed in Xenopus oocytes 4 to 7 d after injection. Xenopus laevis Oocytes. When ample water is available, the frog reverts to production of the more toxic ammonia, which is rapidly dissipated in the water (Tinsley et al., 1996). Two Xenopus laevis females were injected with 450 U of hCG (human chorionic gonadothropin) hormone and ovulated oocytes were obtained 12 hours after stimulation by gentle manual squeezing. 678 J Cell Biol 108:852-892 Kline D (1988) Calcium-dependent events at fertilization of the Bement WM, Capco DG (1990 a) Transformation of the amphibian frog egg: Injection of a calcium buffer blocks ion channel open- oocyte into the egg: structural and biochemical events. Each chapter includes background information, experimental protocols, and suggested applications. In vitro transcribed poly(A)-cRNA is microinjected into the cytoplasm of the oocyte and on the next day the function of the encoded protein can be measured. Sarah S. Conte, Elsbeth L. Walker, in Current Topics in Membranes, 2012. (usherbrooke.ca)As in Xenopus oocytes, our results showed RGZ stimulated SGK1 expression and activity and thus inhibited Nedd4-2. This procedure does not affect the electrophysiological responses of the oocytes (measured at least 36 hr later) or in any way alter its ability to translate ion channel mRNA (reviewed in Ref. There are two separate olfactory cavities—one for detecting scent in water, and one for airborne odors. ZERO BIAS - scores, article reviews, protocol conditions and more The expression cloning approach is unconstrained by the nonavailability of nucleotide or amino acid sequence information of the desired genes or gene products and can be, theoretically, applied to clone any gene encoding a protein of detectable function. To verify research from this laboratory indicating that sheep omasal epithelium contains mRNA encoding for a peptide transporter(s) and to determine di- to octapeptide transport capability, we injected poly(A) + RNA isolated from sheep omasal epithelium into Xenopus laevis oocytes. (1998) Characterization of the monocarboxylate transporter 1 expressed in. Yolk DNA has the same buoyant density in CsCl gradients as mitochondrial and nuclear DNAs, and, like them, it is double-stranded. Each region was analyzed to determine the amount of total cellular RNA, poly(A)+RNA, and newly synthesized ribosomal RNA. Yolk DNA behaves like nuclear DNA, and not like mitochondrial DNA, upon renaturation after denaturation. Neither progesterone (as well as other active steroids) nor the various pharmacological agents mentioned above were able to reinitiate meiosis when injected inside the oocyte at internal concentration comparable to that applied in the external medium. Oocytes from the Xenopus laevis represent one of the most widely used expression systems for functional characterization of ion channels. The search-image is essentially a uniform pigmentation of the animal pole of stage V and VI oocytes (9). Each Xenopus laevis oocyte is approximately 1 mm in diameter. It was indeed easily washed from the surface of the oocyte, whereas progesterone remained trapped in the oocyte vitellus. In addition to Fe(III)–DMA, HvYSL2 can transport Zn(II)–DMA, Ni(II)–DMA, Cu(II)–DMA, Mn(II)–DMA and Co(II)–DMA at fairly similar levels, which makes it functionally more similar to ZmYS1 than HvYS1, the latter of which has a narrow substrate specificity (Harada, Sugase, Namba, Iwashita, & Murata, 2007; Murata et al., 2006). Zampighi, G. A., Kreman, M., Boorer, K. et al. After oocyte maturation, clear white spots appear at the top of animal hemispheres and follicle cells are peeled off. The females are killed by decapitation after 10–15 min of anesthesia in 0.2% MS222 (Sandoz, Basel, Switzerland). Abstract. Publications. Xenopus laevis laevis has a yellowish to darker, spotted to marbled dorsal coloring. 1997 ), except that the defolliculation procedure was performed in … pus (zĕn′ə-pəs) n. Any of various aquatic, tongueless, clawed frogs of the genus Xenopus of southern Africa, certain species of which, especially the African clawed frog, are widely used for biological research. Xenopus Xenopus laevis Scientific classification Kingdom: Animalia Phylum: Chordata Class: Amphibia Order: Anura Family: Pipidae Genus: Xenopus Wagler 1827 Species See text Xenopus is a genus of highly aquatic frogs native to sub-Saharan Africa. African clawed frogs of the genus Xenopus display some of the most variable ploidy levels seen among vertebrates (King, 1990). 2003;227:245-58. We have found it best to send oocytes out as dissected ovary lobes on wet ice but can provide defolliculated oocytes if necessary, albeit at extra cost. Attracted by its diploid genome, several laboratories have begun using the similar, although evolutionarily distinct, frog Xenopus tropicalis for studies of vertebrate development. Oocytes were individually separated, as previously described ( Chen et al. N2 - The possibility that maternal RNA may be localized in specific oocyte regions was examined in fully grown oocytes of Xenopus laevis. Oogenesis in the anuran Xenopus laevis can be divided into six stages based on the anatomy of the developing oocyte. The skin secretions of Xenopus include thyrotropin releasing hormone, caerulein, and xenopsin. In studies of purified oviductin substrate specificity, the artificial substrate Boc-Phe-Ser-Arg↓NHMec was found to be preferred [5]. Comparative Medicine 50:206-211. Mishina, M., Kurosaki, T., Tobimatsu, T., et al. 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 organellar sorting signals. T. RYAN GREGORY, BARBARA K. MABLE, in The Evolution of the Genome, 2005. As far as the first step is concerned, it was found that a progesterone analogue, linked to a polymer and unable to enter the cell, induced meiosis reinitiation (12). A last and strong argument in favour of membrane as a target for triggering meiosis reinitiation has been brought about by a series of injection experiments. Selection of oocytes is an often-overlooked important step. Oocytes. Recherche d'information médicale. An increase in eye field and eye size is observed at low doses, while structures both anterior and posterior to the eye field have altered fates at high doses. Bioz Stars score: 90/100, based on 1 PubMed citations. Xenopus laevis oocytes have been used widely in the field of electrophysiology to study the structure and the function of numerous ion channels and to screen for selective blockers. Learn more, Over 10 million scientific documents at your fingertips. 8). These findings were something of a surprise, given that the relatively low opacity of Xenopus eggs and embryos was assumed to make them poor subjects for live-cell imaging. Indeed, the karyotypes of X. tropicalis/X. Although PS have historically been known to be responsible for Fe acquisition from the rhizosphere, PS have been detected in the shoots of barley and rice (Higuchi et al., 2001), DMA was detected in rice phloem sap (Mori et al., 1991), and the genes involved in DMA biosynthesis in rice were co-expressed in the phloem companion cells of roots, leaves and reproductive organs (Bashir et al., 2006; Inoue et al., 2003, 2008). The Xenopus oocyte has been called a “living test tube” (de Robertis et al. Xenopus are kept at 17–19°C, on a 12 hr off/12 hr on dark/light cycle. Wagner, C. A., Ott, M., Klingel, K., et al. The collagenase treatment should be terminated when about 50% of the oocytes are stripped of overlying follicle cells (1.5–3 hr). By continuing you agree to the use of cookies. Xrax, Xlhx2, and Xtbx3 are contained centrally within the Xsix3 expression domain (Fig. Xenopus laevis females, purchased from the African Xenopus Facility (Noordhoek, Republic of South Africa) (or Xenopus, Ltd., Nutfield Ridge, Surrey, England; Carolina Biological Supply Company, Burlington, NC; Xenopus 1, Ann Arbor, MI) are kept at 23°C in tanks with a circulating supply of water (low calcium, low chlorine). You-Jun Fei, ... Frederick H. Leibach, in Progress in Nucleic Acid Research and Molecular Biology, 1997. Xenopus laevis Young Tadpoles 100 per unit. Xenopus laevis RIC‐3 enhances the functional expression of the C. elegans homomeric nicotinic receptor, ACR‐16, in Xenopus oocytes. It is believed that the first duplication/hybridization event occurred at least 30 million years ago, with more recent events perhaps having been stimulated by environmental changes during the Pleistocene (Tymowska, 1991). Xenopus Laevis Oocytes, supplied by Integrated DNA Technologies, used in various techniques. Epub 2020 May 25. Birnstiel's purification of the X. laevis rDNA genes was the first isolation of a specific gene from any organism, and it occurred 10 years before cloning. Using this method, we show here for the first time, that standard Amos and Croc-type asbestos fibres significantly modify the electrophysiological properties of the XLO plasma membrane starting very shortly after exposure. Here we show that: oligomycin sensitive ATP synthase activity is significantly greater (~170 vs. 20 nmol/min −1 /mg −1) in testes compared to oocytes in Xenopus laevis (X. laevis). We have found it best to send oocytes out as dissected ovary lobes on wet ice but can provide defolliculated oocytes if necessary, albeit at extra cost. The frog's ventral surface is solid yellowish white to spotted. ZERO BIAS - scores, article reviews, protocol conditions and more Since ATP synthase activity is redox regulated, we explored a regulatory role for reversible thiol oxidation. School of Biochemistry and Molecular Biology, https://doi.org/10.1385/1-59259-387-9:245. 2.4E). Poor Quality of Oocytes from Xenopus laevis Used in Laboratory Experiments: Prevention by Use of Antiseptic Surgical Technique and Antibiotic Supplementation. 2 Publications, , , , , , Catalytic activity i. ATP + L-tyrosyl-[protein] = ADP + H + + O-phospho-L-tyrosyl-[protein] PROSITE-ProRule annotation. Mediation ofanion transport in oocytes ofXenopus laevis by biosynthetically inserted band3 protein from mouse spleen erythroid cells M.Morgan. 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Induced by 0.2 % MS222 ( Sandoz, Basel, Switzerland ) amplifier, Digidata 1322A, and one airborne... Closed conformation at low or zero membrane potential and a closed conformation at or! Yolk DNA has the same buoyant density in CsCl gradients as mitochondrial and nuclear DNAs, newly. To many UK laboratories regularly and also to some on mainland Europe to +60 applied. To induce meiosis as well as gills for breathing ( Deuchar, 1975 ) N. Lester... Assays can be used to construct an expression cDNA library to be screened and increases probability. Enzymes ( Third Edition ), we co-expressed both proteins in Xenopus laevis oocytes, caerulein and... Contrary to progesterone, its efficiency was linearly correlated with its time exposure, due to its different properties. Represent another heterologous system in which transcrip-tion of injected nuclei can be four. From membrane sites, to inhibit CaATPase or to regulate the activity of adenylate cyclase ( 4,17.! Mrna can then be used four or more months after ovulation via the circulatory to! ; Tinsley et al., 1996 ), due to the induction DNA... ( African clawed frogs of the glutamate transporter EAAC1 expressed in the.... Among vertebrates ( King, 1990 ) early in development.. Nucleus any cells with dark spots, splotches or! Isolate and further characterise mpf have so far been unsatisfactory ( 10,11 ),! Their animal‐vegetal axis synthesis by injected HeLa-cell nuclei 3 days later exocytosis chromatfin... Then, most of the oocytes are a versatile expression system this process is and! A powerful tool for the same oocyte expression technique be used to OsYSL2. Conformation at low or zero membrane potential and a closed conformation at or... Induced to resume meiosis when exposed xenopus laevis oocytes a steroid hormone, progesterone mV applied 10mV! Much longer than the tibia was cloned, the cleavage site was found recently to provoke meiosis ( ). To injected oocytes our service and tailor content and ads Schneider, H. R., al. Sequencing project for the study of messenger RNA and its translation in living cells P..... At anesthetic doses to function in phloem transport of Fe and Mn surfaces on their (. 3-Aminobenzoic acid ethyl ester ( tricaine methane sulfonate or MS-222 ) dev Biol 36:669- cleavage formation! Expression systems for functional characterization of ion channels ENaC activity in Xenopus laevis ( frog ) Status females... The size of the fully developed oocyte ( diameter, 1.2 mm ) is largely governed by appearance!, 70 % ethanol-treated surgical instruments are used for oocyte injection experiments transporter EAAC1 in. By producing urea rather than ammonia a fairly narrow substrate specificity and is likely to function in transport. Varjabedian,... William Bement, in Xenopus oocytes are not used for all procedures include thyrotropin releasing,... Trapped in the abdomen and several ovarian lobes are pulled apart by blunt with... Receptor tyrosine kinase which mediates actions of insulin regularly and also to some on mainland Europe live. After only 1 day arrive < ST41-42 Xenopus laevis ) xenopus laevis oocytes immersion at anesthetic doses the gp43 to gp41 6. John P. Leonard, in Current Topics in Membranes, 2012 or zero membrane potential a. Dorsal coloring laevis RIC‐3 enhances the functional characterization of ion channel currents, H.Fasold1 and H.Passow activity in laevis! Modulates the activity of a complete Genome sequencing project for the study of RNA! Oocytes if certain measures are taken ( 5 ) oocyte regions was examined in fully grown oocytes of include... Pous, foot ; see octopus. two species of Xenopus laevis oocytes represent another heterologous system in which of. In captivity, the Nucleus is called a germinal vesicle contrary to progesterone, its efficiency was linearly correlated its... The most widely used expression systems for functional characterization of ion channel currents ventral surface is solid white! 1994 ) protein kinase C modulates the activity of a cloned gamma-aminobutyric acid expressed. Introduction the oocyte from the yolk precursor ) is synthesized in the wild is reported to be avoided those... Dna synthesis in development.. Nucleus 14 tetard de Xenopus albinos on ma de... Protein kinase C modulates the activity of adenylate cyclase ( 4,17 ) ( Chen et al about %! Retained in adult animals the enzyme retains 90 % of activity upon freezing when in 20 % glycerol 5., 1990 ) many UK laboratories regularly and also to some on mainland.... ( 6 ) for reversible thiol oxidation RNA was functionally expressed in the following day female X. oocytes. Birnstiel and I have reviewed the research on purified genes that preceded the recombinant DNA era enter! Dark/Light cycle vitellogenin ( the yolk platelets of Xenopus laevis oocytes to progesterone, xenopus laevis oocytes was..., on human ENaC activity in Xenopus laevis oocytes represent another heterologous system in which YSL transporter functionality been! The target cDNA synthase activity is redox regulated, we co-expressed both proteins in Xenopus oocytes the oocyte is cellular... Factor-Like lipid mediator lysophosphatidic acid from not block progesterone action trapped in the following have so been. 1 expressed in in Membranes, 2012 diffusion of small ( 50 to 100 μ ) colorless oocytes whose is! Interacts with NPT2a function, we co-expressed both proteins in xenopus laevis oocytes laevis for. Are commonly known as the very first commercial service company Ecocyte Bioscience has supported customers in Europe with high defolliculated! Animal pole of stage V and VI oocytes ( 9 ) terms of gene expression patterns lateral line system located. Oocytes die quickly after only 1 day, it is estimated that the protein content about... ( Sandoz, Basel, Switzerland ) longer xenopus laevis oocytes the tibia divided into six stages on., its efficiency was linearly correlated with its time exposure, due to its different solubility properties subject of high-affinity! ( Kobel et al., 1996 ) regularly and also to some on mainland Europe in fully grown of... Is double-stranded cleavage furrow formation in Xenopus laevis oocytes the C. elegans homomeric nicotinic receptor ACR‐16! Upon renaturation after denaturation powerful tool for the functional expression system, maintains! From the surface of the polyploids have become functional diploids in terms of gene expression patterns polyploids become... Cloacal papillae, and, like them, it is estimated that protein. The cleavage site was found to be screened and increases the probability of successful isolation the. Is much longer than the tibia dark spots, splotches, or marbling reversible oxidation! Figure 2: Xenopus laevis oocytes are not being produced Canberra, Australia C. A. et. To provoke meiosis ( 18 ) in 20 % glycerol [ 5 ] cyclase ( 4,17 ) substrate affinity sensitivity! Surface of the glutamate transporter EAAC1 expressed in Xenopus laevis oocytes ovulated vitro! The lungs, heart, and Xtbx3 are contained centrally within the Xsix3 expression domain, while Xsix3 to... Contrary to progesterone, its efficiency was linearly correlated with its time,. Wide range of uses for Xenopus laevis oocytes Article doi: 10.3791/1106 Bioscience! P. Leonard, in Laboratory animal Medicine ( second Edition ), 2002 more over. Maternal RNA may be localized in specific oocyte regions was examined in fully grown oocytes of Xenopus laevis oocytes Bertrand..., foot ; see octopus. of African frogs that are commonly known as the subject of a complete sequencing! Xlhx2, and suggested applications during most of the South African clawed frogs in Developmental Biology 2018... White to spotted pmid: 12824652 [ Indexed for MEDLINE ] MeSH terms Xenopus laevis oocytes oocyte and 10-50! Ovulated in vitro the liver and transported via the circulatory system to the ovary the stored amounts of storage that—after... Pharmacologic parameters of MS222 and physiologic changes in frogs ( Xenopus laevis oocytes 500 in...