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891.
Somayyeh Fahiminiya Valérie Labas Sylvie Chastant-Maillard Nadine Gérard 《Reproductive biology and endocrinology : RB&E》2010,8(1):132
Background
Follicular fluid contains substances involved in follicle activity, cell differentiation and oocyte maturation. Studies of its components may contribute to better understanding of the mechanisms underlying follicular development and oocyte quality. The canine species is characterized by several ovarian activity features that are not extensively described such as preovulatory luteinization, oocyte ovulated at the GV stage (prophase 1) and poly-oocytic follicles. In this study, we examined the hypothesis that the preovulatory LH surge is associated with changes in steroid and protein content of canine follicular fluid prior to ovulation. 相似文献892.
Sekiguchi Lesion Gene Encodes a Cytochrome P450 Monooxygenase That Catalyzes Conversion of Tryptamine to Serotonin in Rice 总被引:1,自引:0,他引:1
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Salma Taboubi Fran?oise Garrouste Fabrice Parat Gilbert Pommier Emilie Faure Sylvie Monferran Hervé Kovacic Maxime Lehmann 《Molecular biology of the cell》2010,21(6):946-955
Insulin-like growth factor-I (IGF-I) activation of phosphoinositol 3-kinase (PI3K) is an essential pathway for keratinocyte migration that is required for epidermis wound healing. We have previously reported that activation of Gα(q/11)-coupled-P2Y2 purinergic receptors by extracellular nucleotides delays keratinocyte wound closure. Here, we report that activation of P2Y2 receptors by extracellular UTP inhibits the IGF-I–induced p110α-PI3K activation. Using siRNA and pharmacological inhibitors, we demonstrate that the UTP antagonistic effects on PI3K pathway are mediated by Gα(q/11)—and not G(i/o)—independently of phospholipase Cβ. Purinergic signaling does not affect the formation of the IGF-I receptor/insulin receptor substrate-I/p85 complex, but blocks the activity of a membrane-targeted active p110α mutant, indicating that UTP acts downstream of PI3K membrane recruitment. UTP was also found to efficiently attenuate, within few minutes, the IGF-I–induced PI3K-controlled translocation of the actin-nucleating protein cortactin to the plasma membrane. This supports the UTP ability to alter later migratory events. Indeed, UTP inhibits keratinocyte spreading and migration promoted by either IGF-I or a membrane-targeted active p110α mutant, in a Gα(q/11)-dependent manner both. These findings provide new insight into the signaling cross-talk between receptor tyrosine kinase and Gα(q/11)-coupled receptors, which mediate opposite effects on p110α-PI3K activity and keratinocyte migration. 相似文献
896.
Rory J. Michelland Sylvie Combes Valérie Monteils Laurent Cauquil Thierry Gidenne Laurence Fortun-Lamothe 《Anaerobe》2010,16(2):61-65
This work aimed to study the stability over time of the bacterial community in cæcum and fæces of the rabbit (diversity index and structure) without experimental disturbance and to evaluate its relationships with environmental parameters. Soft and hard fæces of 14 rabbits were sampled for 5 weeks while cæcal content was sampled on the 3rd week (by surgery) and the 5th week (at slaughter). Bacterial communities were assessed by studying CE-SSCP profiles of 16S rRNA genes fragments. Redox potential, pH, NH3-N concentration and volatile fatty acid concentrations were measured in the cæcum. Data showed that bacterial communities of soft and hard fæces barely differed from that of the cæcum (ANOSIM-R < 0.25; p < 0.05). Without disturbance, the bacterial communities of fæces were stable over time (ANOSIM-R < 0.25; p < 0.001). However, the bacterial communities of cæcum and fæces were affected by the surgery (ANOSIM-R = 0.22–0.33; p < 0.001). The cæcal content was an acidic (pH = 6.03 ± 0.33) and an anaerobic environment (redox potential = ?160 ± 43 mV). Only the redox potential was correlated with the diversity index of the bacterial community of the cæcum (R2 = 0.35; p < 0.05) and no environmental parameters were correlated to its structure. 相似文献
897.
Carolina Varela Chavez Grégory Jubelin Gabriel Courties Aurélie Gomard Nadège Ginibre Sylvie Pages Frédéric Taïeb Pierre-Alain Girard Eric Oswald Alain Givaudan Robert Zumbihl Jean-Michel Escoubas 《Microbes and infection / Institut Pasteur》2010,12(14-15):1208-1218
Cycle inhibiting factors (Cif) constitute a broad family of cyclomodulins present in bacterial pathogens of invertebrates and mammals. Cif proteins are thought to be type III effectors capable of arresting the cell cycle at G2/M phase transition in human cell lines. We report here the first direct functional analysis of CifPl, from the entomopathogenic bacterium Photorhabdus luminescens, in its insect host. The cifPl gene was expressed in P. luminescens cultures in vitro. The resulting protein was released into the culture medium, unlike the well characterized type III effector LopT. During locust infection, cifPl was expressed in both the hemolymph and the hematopoietic organ, but was not essential for P. luminescens virulence. CifPl inhibited proliferation of the insect cell line Sf9, by blocking the cell cycle at the G2/M phase transition. It also triggered host cell death by apoptosis. The integrity of the CifPl catalytic triad is essential for the cell cycle arrest and pro-apoptotic activities of this protein. These results highlight, for the first time, the dual role of Cif in the control of host cell proliferation and apoptotic death in a non-mammalian cell line. 相似文献
898.
Bourlaye Fofana Xing‐Hai Yao Christof Rampitsch Sylvie Cloutier John A. Wilkins B. L. Grégoire Nyomba 《Proteomics》2010,10(3):417-434
To gain more insights into the translational and PTM that occur in rat offspring exposed to alcohol in utero, 2‐D PAGE with total, phospho‐ and glycoprotein staining and MALDI‐MS/MS and database searching were conducted. The results, based on fold‐change expression, revealed a down‐regulation of total protein expression by prenatal alcohol exposure in 7‐day‐old and 3‐month‐old rats. There was an up‐regulation of protein phosphorylation but a down‐regulation of glycosylation by prenatal alcohol exposure in both age groups. Of 31 protein spots examined per group, differentially expressed proteins were identified as ferritin light chain, aldo‐keto reductase, tumor rejection antigen gp96, fructose‐1,6‐bisphosphatase, glycerol‐3‐phosphate dehydrogenase, malate dehydrogenase, and γ‐actin. Increased phosphorylation was observed in proteins such as calmodulin, gluthatione S‐transferase, glucose regulated protein 58, α‐enolase, eukaryotic translation elongation factor 1 β‐2, riboprotein large P2, agmatinase, ornithine carbamoyltransferase, quinolinate phosphoribosyltransferase, formimidoyltransferase cyclodeaminase, and actin. In addition, glycosylation of adenosine kinase, adenosylhomocysteine hydrolase, and 3‐hydroxyanthranilate dioxygenase was reduced. Pathways affected by these protein alterations include cell signaling, cellular stress, protein synthesis, cytoskeleton, as well as glucose, aminoacid, adenosine and energy metabolism. The activity of the gluconeogenic enzyme fructose‐1,6‐bisphosphatase was elevated by prenatal alcohol. The observations may have important physiological implications. 相似文献
899.
Sylvie Pažoutová Petr Šrůtka Jaroslav Holuša Milada Chudíčková Miroslav Kolařík 《Mycological Progress》2010,9(4):501-507
The inconspicuous inner-bark parasite Obolarina dryophila is reported from wood of Quercus petraea and as an endophyte of Salix alba. In addition, viable ascospores of O. dryophila have been found in the gut of the oak bark weevil Gasterocercus depressirostris, suggesting a possible dissemination mechanism for the fungus. A phylogenetic analysis based on three genes (nrDNA, actin,
β-tubulin) placed Obolarina inside the genus Biscogniauxia as a close relative of the oak pathogens B. atropunctata and B. mediterranea. 相似文献
900.