Vitellogenin Receptor
Mostrando 1-12 de 53 artigos, teses e dissertações.
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1. Endocrinologia e controle da vitelogênese em carrapatos = Endocrinology and control of tick vitellogenesis / Endocrinology and control of tick vitellogenesis
Background: Ticks are distributed worldwide, with impacts on human and animal health. The cattle tick Rhipicephalus (Boophilus) microplus is the main parasite that affects livestock in tropical and subtropical regions of the world, causing large economical losses. Tick control methods are based on the application of chemical acaricides, which has resulted in
Publicado em: 2011
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2. Endocrinologia e controle de vitelogênese em carrapatos / Endocrinology and control of tick vitellogenesis
Background: Ticks are distributed worldwide, with impacts on human and animal health. The cattle tick Rhipicephalus (Boophilus) microplus is the main parasite that affects livestock in tropical and subtropical regions of the world, causing large economical losses. Tick control methods are based on the application of chemical acaricides, which has resulted in
Publicado em: 2011
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3. Culex quinquefasciatus vitellogenesis / Vitelogênese do mosquito Culex quinquefasciatus
Como em outros mosquitos, os trofócitos do corpo gorduroso de Cx. quinquefasciatus sintetizam vitelogenina (Vg), principal proteína armazenada pelo ovócito, formada por duas subunidades de 200 e 86 kDa. A ultraestrutura dos trofócitos revela o rápido desenvolvimento da maquinaria biossintética após a alimentação com sangue (aa) e a consecutiva degra
Publicado em: 2010
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4. Specific modulation of the transcription of cloned avian vitellogenin II gene by estradiol-receptor complex in vitro.
Avian vitellogenin-cauliflower mosaic virus hybrid gene is effectively transcribed in vitro in the homologous embryonic liver nuclei system. The transcription of the hybrid gene is modulated by the addition of an estradiol-receptor preparation that has been shown to bind selectively to an upstream region of cloned vitellogenin gene. Stimulation of the transc
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5. Partial purification of estradiol receptor from Xenopus laevis liver and levels of receptor in relation to estradiol concentration.
We have used ammonium sulphate precipitation followed by affinity chromatography to partially purify the estrogen receptor from Xenopus laevis liver which may control the genes for vitellogenin, the precursor of the egg yolk proteins. The rate at which receptor binds estradiol explains the kinetics of the induction of vitellogenin synthesis by estradiol, and
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6. Activation of chromosomal vitellogenin genes in Xenopus oocytes by pure estrogen receptor and independent activation of albumin genes.
We generate pure estrogen receptor protein in Xenopus oocytes by injecting them with estrogen receptor mRNA synthesized in vitro. A chromosomal vitellogenin gene, which normally responds to estrogen only in liver cells, is activated. Primer extension shows that initiation is accurate, and ribonuclease mapping shows that the first exon is correctly spliced ou
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7. Estrogen receptor level determines sex-specific in vitro transcription from the Xenopus vitellogenin promoter.
Female-specific expression of the Xenopus laevis vitellogenin gene was reconstituted in vitro by addition of recombinant vaccinia-virus-produced estrogen receptor to nuclear extracts from male livers, in which this gene is silent. Transcription enhancement was at least 30 times and was selectively restricted to vitellogenin templates containing the estrogen-
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8. Estrogen and progesterone receptor-binding sites on the chicken vitellogenin II gene: synergism of steroid hormone action.
The chicken vitellogenin II gene is transcriptionally activated by estrogens. In transient transfection experiments in human T47D cells that contain receptors for various steroids, we showed estradiol, progestin, and androgen responses of a chimeric chicken vitellogenin II construct. This construct consists of DNA sequences from -626 to -590 upstream of the
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9. Distribution of estradiol receptor and vitellogenin gene in chick liver chromatin fractions.
The distribution of estradiol receptor and vitellogenin gene was studied in estradiol stimulated chick liver chromatin fractions prepared by limited DNAse II digestion and MgCl2 precipitation. The receptor was found in all fractions, undigested chromatin (P1), Mg2+ insoluble chromatin (P2) and Mg2+ soluble chromatin (S2). This last fraction was rich in acidi
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10. The human estrogen receptor can regulate exogenous but not endogenous vitellogenin gene promoters in a Xenopus cell line.
Transfection of a human estrogen receptor cDNA expression vector (HEO) into cultured Xenopus kidney cells confers estrogen responsiveness to the recipient cells as demonstrated by the hormone dependent expression of co-transfected Xenopus vitellogenin-CAT chimeric genes. The estrogen stimulation of these vit-CAT genes is dependent upon the presence of the vi
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11. Activation of vitellogenin gene transcription is a direct response to estrogen in Xenopus laevis liver.
Estrogen induces the synthesis of vitellogenin mRNA by activating transcription of the vitellogenin genes. Quantitative inhibition of liver protein synthesis by cycloheximide does not prevent activation of vitellogenin gene transcription. The relative transcription rate of the vitellogenin genes in estrogen stimulated liver is similar in control and cyclohex
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12. A single chicken oocyte plasma membrane protein mediates uptake of very low density lipoprotein and vitellogenin.
Specific cell-surface receptors mediate the uptake of plasma proteins into growing oocytes of oviparous species, thereby forming yolk. Quantitatively the most important yolk precursors are the lipoproteins, very low density lipoprotein, and vitellogenin. We show that a single major chicken oocyte plasma membrane protein with an apparent molecular mass of 95