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Alicia Lourteig 《Brittonia》1986,38(3):264-265
Pierre-Émile Gounelle, a French entomologist, collected a few plants in Brazil between 1884 and 1890 that are deposited at P. He collected in the states of Bahia, Minas Gerais, Pará, Pernambuco, Rio de Janeiro, São Paulo, and Santa Catarina. 相似文献
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Vif counteracts a cyclophilin A-imposed inhibition of simian immunodeficiency viruses in human cells 下载免费PDF全文
Takeuchi H Buckler-White A Goila-Gaur R Miyagi E Khan MA Opi S Kao S Sokolskaja E Pertel T Luban J Strebel K 《Journal of virology》2007,81(15):8080-8090
Vif is a primate lentiviral accessory protein that is crucial for viral infectivity. Vif counteracts the antiviral activity of host deaminases such as APOBEC3G and APOBEC3F. We now report a novel function of African green monkey simian immunodeficiency virus (SIVagm) Vif that promotes replication of SIVagm in human cells lacking detectable deaminase activity. We found that cyclophilin A (CypA) was excluded from wild-type SIV particles but was efficiently packaged into vif-deficient SIVagm virions. The presence of CypA in vif-defective SIVagm was correlated with reduced viral replication. Infection of CypA knockout Jurkat cells or treatment of Jurkat cells with cyclosporine A eliminated the Vif-sensitive inhibition and resulted in replication profiles that were similar for wild-type and vif-deficient SIVagm. Importantly, the inhibitory effect of CypA was restricted to virus-producing cells and was TRIM5alpha independent. The abilities of SIVagm Vif to inhibit encapsidation of CypA and to increase viral infectivity were shared by rhesus macaque SIV Vif and thus seem to be general properties of SIV Vif proteins. Exclusion of CypA from SIVagm particles was not associated with intracellular degradation, suggesting a mode of Vif action distinct from that proposed for APOBEC3G. This is the first report of a novel vif-sensitive antiviral activity of human CypA that may limit zoonotic transmission of SIV and the first demonstration of CypA encapsidation into a virus other than human immunodeficiency virus type 1. 相似文献
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Géraldine Carlier Alicia Maugein Corinne Cordier Séverine Pechberty Meriem Garfa-Traoré Patrick Martin Rapha?l Scharfmann Olivier Albagli 《PloS one》2014,9(9)
Regulation of cell cycle in beta cells is poorly understood, especially in humans. We exploited here the recently described human pancreatic beta cell line EndoC-βH2 to set up experimental systems for cell cycle studies. We derived 2 populations from EndoC-βH2 cells that stably harbor the 2 genes encoding the Fucci fluorescent indicators of cell cycle, either from two vectors, or from a unique bicistronic vector. In proliferating non-synchronized cells, the 2 Fucci indicators revealed cells in the expected phases of cell cycle, with orange and green cells being in G1 and S/G2/M cells, respectively, and allowed the sorting of cells in different substeps of G1. The Fucci indicators also faithfully red out alterations in human beta cell proliferative activity since a mitogen-rich medium decreased the proportion of orange cells and inflated the green population, while reciprocal changes were observed when cells were induced to cease proliferation and increased expression of some beta cell genes. In the last situation, acquisition of a more differentiated beta cell phenotype correlates with an increased intensity in orange fluorescence. Hence Fucci beta cell lines provide new tools to address important questions regarding human beta cell cycle and differentiation. 相似文献
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David K. Clarke Farooq Nasar Siew Chong J. Erik Johnson John W. Coleman Margaret Lee Susan E. Witko Cheryl S. Kotash Rashed Abdullah Shakuntala Megati Amara Luckay Becky Nowak Andrew Lackner Roger E. Price Peter Little Narender Kalyan Valerie Randolf Ali Javadian Timothy J. Zamb Christopher L. Parks Michael A. Egan John Eldridge Michael Hendry Stephen A. Udem 《Journal of virology》2014,88(12):6690-6701
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Elizabeth M Freeburg Alicia A Goyeneche Erin E Seidel Carlos M Telleria 《Cancer cell international》2009,9(1):4