Disease relevance of Larva

• In APV- or MK801/NMDA-treated tadpoles, labeled ganglion cells covered 17% and 10% of the retinal area, respectively [1].
• Progressive deletion constructs of both the promoters have been made using a PCR based approach and the basal promoter activities studied in Xenopus tadpole cell line (XTC), Xenopus adult kidney fibroblast cell line (A6), human hepatoma cell line (HepG2), normal rat kidney cell line (NRK), and Chinese hamster ovary cell line (CHO) [2].
• Hypercapnia induced a massive transfer of HCO3- equivalents and Ca2+ from the tadpoles to the environment, which lasted some 4-6 h [3].
• Chronic hypoxia in tadpoles produced little change in whole blood P50, and no significant change in any other blood variable [4].
• On the other hand, RH-5849 showed no acute toxicity to tadpoles during the 96 h exposure even it was saturated in the test solutions [5].

Psychiatry related information on Larva

• A vasopressin receptor antagonist (d(CH2)5[Tyr(Me)2]AVP administered ip or icv) significantly increased locomotor activity in tadpoles, compared to controls [6].
• Towards understanding the ontogeny of energy balance regulation in vertebrates we analyzed the responses of corticotropin-releasing factor (CRF) and corticosterone to food deprivation in the Western spadefoot toad (Spea hammondii) at three developmental stages: premetamorphic tadpole, prometamorphic tadpole, and juvenile [7].

High impact information on Larva

• WDR5 is essential for vertebrate development, in that WDR5-depleted X. laevis tadpoles exhibit a variety of developmental defects and abnormal spatial Hox gene expression [8].
• Niazi and Saxena first observed that vitamin A has an inhibitory and modifying influence on tail regeneration in Bufo andersonii tadpoles [9].
• We have now determined the sequence of the alpha- and beta-globin chains of coelacanth haemoglobin and compared them with all known haemoglobins of bony and cartilaginous fish as well as those of tadpoles and adult amphibians [10].
• Our results indicate that thyroxine, the hormone which causes metamorphosis in the frog Xenopus laevis, can induce precociously in a pre-metamorphic tadpole the ipsilateral retinothalamic projection, a retinofugal pathway which normally develops during metamorphosis [11].
• Increase in binding capacity for triiodothyronine in tadpole tail nuclei during metamorphosis [12].

Chemical compound and disease context of Larva

• In the Xenopus tadpole there are three different serotonin-containing amacrine cells: large, brightly fluorescent (LB), and small, dimly fluorescent (SD) cells in the inner nuclear layer and displaced (DIS) cells in the ganglion cell layer [13].
• An intraperitoneal (ip) injection of arginine vasotocin (AVT) in tadpoles (stages V, X, or XVII) produced an immediate and dose-dependent inhibition of locomotor activity [6].
• Addition of NMA or glutamate to a bath containing an in vitro tadpole spinal cord preparation elicited ventral root motor activity characteristic of swimming, but without a rostrocaudal phase lag [14].
• Daily treatment with either ovine prolactin (oPRL) or ovine growth hormone (oGH) prevented the weight loss and the increase in extracellular [Na+] that occurred when tadpoles were transferred to 18 degrees C. Neither propylthiouracil (PTU) nor arginine vasotocin (AVT) were effective in countering temperature-induced weight loss in tadpoles [15].
• The acute toxicity of technical-grade glyphosate acid, glyphosate isopropylamine, and three glyphosate formulations was determined for adults of one species and tadpoles of four species of southwestern Australian frogs in 48-h static/renewal tests [16].

Biological context of Larva

• Thyroid hormone induces apoptosis in primary cell cultures of tadpole intestine: cell type specificity and effects of extracellular matrix [17].
• These genes respond directly to TH as demonstrated by the resistance of up-regulation to protein synthesis inhibition in the cultured cells or in tadpoles [18].
• During premetamorphic stages, Xenopus laevis tadpoles expressing either a dominant-negative thyroid hormone (TH) receptor or a type-III iodothyronine deiodinase transgene in the nervous system have reduced TH-induced proliferation in the spinal cord and produce fewer hindlimb-innervating motorneurons [19].
• The missense mutations were analyzed functionally in the photoreceptors of Xenopus laevis tadpoles, which revealed mislocalization of ABCA4 protein [20].
• We have identified a sequence of 22 highly conserved nucleotides in the 5' untranslated sequences of chicken, human, and tadpole ferritin H-subunit genes and propose that this conserved sequence may regulate iron-modulated translation of ferritin H-subunit mRNAs [21].

Anatomical context of Larva

• In Xenopus tadpole VEGF-C knockdowns and in mice lacking Vegfc, the proliferation of neural progenitors expressing VEGFR-3 was severely reduced, in the absence of intracerebral blood vessel defects [22].
• Transgenic tadpoles that express a dominant negative thyroid hormone (TH) receptor specifically in their skin undergo normal metamorphosis, with one exception: they retain a larval epidermis over the developing adult epithelium [23].
• Total RNA of tadpole and frog (Rana catesbeiana) liver was isolated by either 7 or 8 M guanidine . HCl extraction and translated in a cell-free protein-synthesizing system derived from rabbit reticulocytes [24].
• Exposure of tadpoles at premetamorphic stages (48-52) to exogenous thyroid hormone (T3) substantially enhanced the accumulation of TR mRNA, especially that of TR beta message, which could explain the accelerated increase in sensitivity of tadpoles to thyroid hormones at the onset of natural metamorphosis.(ABSTRACT TRUNCATED AT 400 WORDS)[25]
• Interestingly, v-erbA mRNA injection and citral treatment of gastrula stage embryos resulted in tadpoles with a similar set of developmental defects [26].

Associations of Larva with chemical compounds

• Thus the thyroxine-induced synthesis of carbamyl phosphate synthetase I in tadpole liver is at least partly due to an increase of translatable mRNA for this enzyme [24].
• This difference is because of the conversion of T4 to T3 in target cells of the tadpole catalyzed by the enzyme type II iodothyronine deiodinase (D2) and the local effect (cell autonomy) of this activity [27].
• Antipain had no significant effect on leucine incorporation into total protein of tadpole liver [28].
• The PTU-reared tadpoles remained by external criteria at stage 54 [29].
• It is concluded that the myoplasm of ascidian eggs contains an intermediate filament-like cytoskeletal network which is missing in anural species that have modified or eliminated the tadpole larva [30].

Gene context of Larva

• Furthermore, overexpression of a dominant-negative N-CoR in tadpole tail muscle led to increased transcription from a T(3)-dependent promoter [31].
• We found that TBLR1, SMRT, and N-CoR are recruited to T(3)-inducible promoters in premetamorphic tadpoles and are released upon T(3) treatment, which induces metamorphosis [32].
• Using the in vivo tadpole assay system, we further show that misexpression of GLI1 induces CNS hyperproliferation that depends on the activation of endogenous Gli1 function [33].
• We show that CRF is expressed in tadpole tail, is up-regulated by environmental stressors, and is cytoprotective [34].
• The vri gene encodes a new member of the bZIP family of transcription factors closely related to gene 9 of Xenopus laevis, induced by thyroid hormone during the tadpole tail resorption program, and NF-IL3A, a human T cell transcription factor that transactivates the interleukin-3 promoter [35].

Analytical, diagnostic and therapeutic context of Larva

• In situ hybridization analysis of the expression of Xhox3 in neural tissue shows that it is restricted within the neural tube and the cranial neural crest during the tailbud-early tadpole stages [36].
• Immunohistochemistry by using monoclonal antibodies named A5 and B2, which specifically recognize cell surface proteins the neuropilin and the plexin, respectively, revealed that olfactory axons in Xenopus tadpoles were classified into several subgroups by virtue of the expression levels of these two cell surface molecules [37].
• In whites and blacks, nocturnal (dark phase, sleeping) melatonin levels were almost always elevated to 0.05-0.1 ng/ml plasma compared with lower or undetectable levels during the day, measured by the tadpole bioassay [38].
• We now demonstrate that PRL prevents the rapid T3-induced upregulation of TR alpha and beta mRNAs in stages 50-54 Xenopus tadpoles and in organ cultures of tadpole tails [39].
• We confirmed transformation and expression by Northern blot analysis of the recombinant yeast, by Western blot analysis using an antibody against Escherichia coli-expressed TFH, and with Prussian blue staining that indicated that the yeast-expressed tadpole ferritin was assembled into a complex that could bind iron [40].

References