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81.
Sol-Foulon N Sourisseau M Porrot F Thoulouze MI Trouillet C Nobile C Blanchet F di Bartolo V Noraz N Taylor N Alcover A Hivroz C Schwartz O 《The EMBO journal》2007,26(2):516-526
HIV efficiently spreads in lymphocytes, likely through virological synapses (VSs). These cell-cell junctions share some characteristics with immunological synapses, but cellular proteins required for their constitution remain poorly characterized. We have examined here the role of ZAP-70, a key kinase regulating T-cell activation and immunological synapse formation, in HIV replication. In lymphocytes deficient for ZAP-70, or expressing a kinase-dead mutant of the protein, HIV replication was strikingly delayed. We have characterized further this replication defect. ZAP-70 was dispensable for the early steps of viral cycle, from entry to expression of viral proteins. However, in the absence of ZAP-70, intracellular Gag localization was impaired. ZAP-70 was required in infected donor cells for efficient cell-to-cell HIV transmission to recipients and for formation of VSs. These results bring novel insights into the links that exist between T-cell activation and HIV spread, and suggest that HIV usurps components of the immunological synapse machinery to ensure its own spread through cell-to-cell contacts. 相似文献
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Appino S Pregel P Manuali E Vincenti L Rota A Carnieletto P Tiberi C Bollo E 《Animal reproduction science》2007,98(3-4):350-356
Bovine infertility is a major cause of loss in the livestock industry. In the present study bovine oviduct cell cultures were infected with a Chlamydophila abortus strain. A direct evaluation of infection was performed by means of May Grünwald-Giemsa and immunocytochemistry for chlamydial LPS, which revealed inclusion bodies and vacuolisation. SEM and TEM analysis of infected cells showed various degrees of cell damage and conglutination of microvilli. This finding suggests that cattle infertility may result from an alteration of oviduct environment caused by multiplication of C. abortus. This microorganism, among other infectious agents, could be considered a potential causative agent of bovine infertility. 相似文献
84.
The phylogeny of polar fishes and the structure,function and molecular evolution of hemoglobin 总被引:1,自引:0,他引:1
Fishes thriving in polar habitats offer many opportunities for comparative approaches to understanding protein thermal adaptations.
Investigations on the remarkable evolutionary adaptations to these environments of basic proteins such as hemoglobin, the
oxygen carrier, can provide new insights into the mechanisms studied in temperate organisms and can shed light on convergent
processes evolved in response to thermal adaptations. At the molecular level, hemoglobins are one of the most intriguing systems
for studying the relationships between environmental conditions and adaptations. This review summarizes the current knowledge
on molecular structure, biological function and phylogeny of hemoglobins of fish species living in both polar habitats but
having different evolutionary histories. In benthic, non-migratory, cold-adapted fishes, the stability of thermal conditions
may have generated no or few variations in selective pressures on globin sequences through evolutionary time, so that sequences
retain the species phylogenetic “signal”. In pelagic, migratory, cold-adapted or temperate fishes, variations in selective
pressures on globin sequences caused by variations in temperature accompanying the dynamic life style may have disrupted the
phylogenetic “signal” in phenetic trees. 相似文献
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Cinzia Comino Sergio Lanteri Ezio Portis Alberto Acquadro Annalisa Romani Alain Hehn Romain Larbat Frédéric Bourgaud 《BMC plant biology》2007,7(1):14
Background
Cynara cardunculus L. is an edible plant of pharmaceutical interest, in particular with respect to the polyphenolic content of its leaves. It includes three taxa: globe artichoke, cultivated cardoon, and wild cardoon. The dominating phenolics are the di-caffeoylquinic acids (such as cynarin), which are largely restricted to Cynara species, along with their precursor, chlorogenic acid (CGA). The scope of this study is to better understand CGA synthesis in this plant. 相似文献87.
Francesca Ghirga Federica Aiello Sara Toscano Cinzia Ingallina Mariangela Siler Danilo Cucchi Agnese Po Evelina Miele Davide D'Amico Gianluca Canettieri Enrico De Smaele Elisabetta Ferretti Isabella Screpanti Gloria Uccello Barretta Maurizio Botta Bruno Botta Alberto Gulino Lucia Di Marcotullio 《The EMBO journal》2015,34(2):200-217
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