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1.
Nicole Crozet D. Huneau Vronique Desmedt Marie-Claire Thron D. Szllsi Suzanne Torrs Claude Svellec 《Molecular reproduction and development》1987,16(2):159-170
Ovine tubal (n = 87) and ovarian in vitro matured oocytes (n = 99) were fertilized in vitro with ejaculated spermatozoa capacitated for 8 h in modified defined medium buffered with Hepes. High levels of fertilization were obtained as assessed by development to two-to six-cell stage within 40 h (75. 8% for ovulated and 62. 6% for in vitro matured oocytes). Electron microscope analysis of oocytes 20–22 h after insemination indicated that in vitro fertilization approximated the in vivo events. Embryos (two- to six-cell) were transferred surgically to the oviducts of pseudopregnant rabbits. Three days later, 42 (from ovulated oocytes) and 15 (from in vitro matured oocytes) embryos were recovered; 26 (61. 9%) and 10 (66. 6%), respectively, had cleaved at least once. Embryos incubated in vivo (n = 20 from ovulated oocytes; n = 9 from in vitro matured oocytes) were transferred surgically to the uteri of seven and four recipient ewes resulting in four and two pregnancies, respectively, from which three and one, respectively, have been maintained ( > 3 months). The first lamb resulting from the in vitro fertilization of an ovulated oocyte was born. In addition, six embryos (two- to four-cell) from tubal oocytes and ten embryos (two- to six-cell) from in vitro matured oocytes were directly transferred to the oviducts of two and three ewes, respectively. Two pregnancies resulting from in vitro matured fertilized oocytes are in progress ( > 3 months). 相似文献
2.
Tracy L. Rankin Michael K. Holland Marie-Claire Orgebin-Crist 《Molecular reproduction and development》1989,24(4):439-451
Glycoproteins from luminal fluid of the mouse cauda epiciidymidis have been compared with glycoproteins from Triton X-100 extracts of mouse spermatozoa from varying regions of the epididymis, using lectins with specific affinity for different sugar residues. Concanavalin A recognizes 11 glycocomponents on Western blots of fractionated caudal fluid; wheat germ agglutinin (WGA) binds 12 proteins; Ulex europaeus agglutinin (UEA) binds seven; and Dolichos biflorus agglutinin (DBA) recognizes nine. Several of these glycoproteins display an affinity for more than one lectin, indicating a diversity in their exposed carbohydrate residues; whereas other proteins bind only one of the four lectins used. The results also show that some glycoproteins exhibit a higher affinity for particular lectins. Eight glycoproteins of similar mobility and lectin-binding characteristics are detected in Triton X-100 extracts of spermatozoa from different regions of the epididymis and in caudal fluid. The lectin affinity of some proteins appears or increases in spermatozoa from distal epididymal regions (54 kD, 32 kD), whereas the lectin affinity of others decreases (29 kD, 40 kD). There are differences in lectin affinities between proteins in sperm extracts and in caudal fluid. Some proteins show an affinity for three or four lectins in caudal fluid, but proteins of similar electrophoretic mobility in sperm extracts bind only one or two of the lectins. These data show that glycoproteins of similar mobility are present in caudal fluid and in Triton-X-100 sperm extracts, implying a potential interaction between caudal fluid components and epididymal sperm. 相似文献
3.
Laurent Beuf Sylvie Bédu Marie-Claire Durand Françoise Joset 《Plant molecular biology》1994,25(5):855-864
The involvement of a gene ofSynechocystis PCC6803,icfG, in the co-ordinated regulation of inorganic carbon and glucose metabolism, was established. TheicfG gene codes for a 72 kDa protein, which shows no homology with those registered in data libraries. Expression oficfG required glucose, the actual inducer probably being glucose-6-phosphate, and was independent of light and of the external inorganic carbon concentration. Mutants carrying an inactivated copy oficfG were constructed. Their growth characteristics were identical to those of the wild type under all regimes except in limiting inorganic carbon with glucose being present either before or after the transfer to the limiting conditions. These conditions completely prevented growth, both in the light and in the dark. The inhibition could be relieved by several intermediates of the tricarboxylic acid cycle. Assays of various enzymic activities related to inorganic carbon uptake and to its assimilationvia either the Calvin cycle or phosphoenolpyruvate carboxylase did not reveal the level of action of IcfG. Possible models include a blockage of the assimilation of both carbon sources in the absence of IcfG, or the inhibition of Ci incorporation route(s) essential under limiting inorganic carbon conditions, even when glucose is present, and even in the dark. 相似文献
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5.
Yves Parmentier Andrée Durr Jacqueline Marbach Cathy Hirsinger Marie-Claire Criqui Jacqueline Fleck Elisabeth Jamet 《Plant molecular biology》1995,29(2):279-292
A cDNA clone (6PExt 1.2) encoding a novel extensin was isolated from a cDNA library made from 6 h old mesophyll protoplasts of Nicotiana sylvestris. The screening was performed with a heterologous probe from carrot. The encoded polypeptide showed features characteristic of hydroxyproline-rich glycoproteins such as Ser-(Pro)4 repeats and a high content in Tyr and Lys residues. The presence of four Tyr-X-Tyr-Lys motifs suggests the possibility for intramolecular isodityrosine cross-links whereas three Val-Tyr-Lys motifs may participate in intermolecular cross-links. The analysis of genomic DNA gel blots using both the N. sylvestris and the carrot clones as probes showed that the 6PExt 1.2 gene belongs to a complex multigene family encoding extensin and extensin-related polypeptides in N. sylvestris as well as in related Nicotianeae including a laboratory hybrid. This was confirmed by the analysis of RNA gel blots: a set of mRNAs ranging in size from 0.3 kb to 3.5 kb was found by the carrot extensin probe. The 6PExt 1.2 probe found a 1.2 kb mRNA in protoplasts and in wounded tissues as well as a 0.9 kb mRNA which seemed to be stem-specific. The gene encoding 6PExt 1.2 was induced by wounding in protoplasts, in leaf strips and after Agrobacterium tumefaciens infection of stems. 相似文献
6.
Marie-Claire Meienhofer Dominique Cottreau Jean-Claude Dreyfus Axel Kahn 《FEBS letters》1980,110(2):219-222
7.
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9.
Dr. Marie-Claire Orgebin-Crist Nader Jahad Loren H. Hoffman 《Cell and tissue research》1976,167(4):515-525
Summary The fertilizing ability of spermatozoa from epididymal tubules maintained in organ cultures from 1 to 7 days was assessed after artificial insemination into receptive does. It was found that spermatozoa from the distal corpus which were already capable of fertilizing eggs prior to the cultures retain this ability for 1 day without addition of hormone and for 3–4 days when testosterone (0.5 g/ml) or 5-dihydrotestosterone (0.5 g/ml) is added to the culture medium. Spermatozoa from the proximal corpus which were not capable of fertilizing eggs prior to the cultures remain so after 1 day in cultures without addition of hormone. Testosterone, 5-dihydrotestosterone, 3-androstanediol, or 3-androstanediol was added to cultures of proximal corpus at a concentration of 0.5 g/ml. Only with 5-DHT is the mean percentage of fertilization significantly higher than the percentage obtained without addition of hormone. Insulin does not potentiate the effect of 5-DHT on sperm fertilizing ability. Epithelial growth factor is ineffective. Spermatozoa from the caput epididymidis kept in cultures for 1 to 4 days remain infertile. The results are discussed in light of the morphological findings presented in the preceding communication and in relation to the physiological requirement for sperm maturation in the epididymis. 相似文献
10.
Phosphorylated p40PHOX as a negative regulator of NADPH oxidase 总被引:5,自引:0,他引:5
Lopes LR Dagher MC Gutierrez A Young B Bouin AP Fuchs A Babior BM 《Biochemistry》2004,43(12):3723-3730
The leukocyte NADPH oxidase catalyzes the production of O(2)(-) from oxygen at the expense of NADPH. Activation of the enzyme requires interaction of the cytosolic factors p47(PHOX), p67(PHOX), and Rac2 with the membrane-associated cytochrome b(558). Activation of the oxidase in a semirecombinant cell-free system in the absence of an amphiphilic activator can be achieved by phosphorylation of the cytosolic factor p47(PHOX) by protein kinase C. Another cytosolic factor, p40(PHOX), was recently shown to be phosphorylated on serine and threonine residues upon activation of NADPH oxidase, but both stimulatory and inhibitory roles were reported. In the present study, we demonstrate that the addition of phosphorylated p40(PHOX) to the cell-free system inhibits NADPH oxidase activated by protein kinase C-phosphorylated p47(PHOX), an effect not observed with the unphosphorylated p40(PHOX). Moreover phosphorylated p40(PHOX) inhibits the oxidase if added before or after full activation of the enzyme. Direct mutagenesis of protein kinase C consensus sites enables us to conclude that phosphorylation of threonine 154 is required for the inhibitory effect of p40(PHOX) to occur. Although the phosphorylated mutants and nonphosphorylated mutants are still able to interact with both p47(PHOX) and p67(PHOX) in pull-down assays, their proteolysis pattern upon thrombin treatment suggests a difference in conformation between the phosphorylated and nonphosphorylated mutants. We postulate that phosphorylation of p40(PHOX) on threonine 154 leads to an inhibitory conformation that shifts the balance toward an inhibitory role and blocks oxidase activation. 相似文献