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91.
Houde M Bertholet S Gagnon E Brunet S Goyette G Laplante A Princiotta MF Thibault P Sacks D Desjardins M 《Nature》2003,425(6956):402-406
The ability to process microbial antigens and present them at the surface of cells is an important aspect of our innate ability to clear infections. It is generally accepted that antigens in the cytoplasm are loaded in the endoplasmic reticulum and presented at the cell surface on major histocompatibility complex (MHC) class I molecules, whereas peptides present in endo/phagocytic compartments are presented on MHC class II molecules. Despite the apparent segregation of the class I and class II pathways, antigens from intracellular pathogens including mycobacteria, Escherichia coli, Salmonella typhimurium, Brucella abortus and Leishmania, have been shown to elicit an MHC class-I-dependent CD8+ T-cell response, a process referred to as cross-presentation. The cellular mechanisms allowing the cross-presentation pathway are poorly understood. Here we show that phagosomes display the elements and properties needed to be self-sufficient for the cross-presentation of exogenous antigens, a newly ascribed function linked to phagocytosis mediated by the endoplasmic reticulum. 相似文献
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Impaired response to interferon-alpha/beta and lethal viral disease in human STAT1 deficiency 总被引:22,自引:0,他引:22
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Irigoien X Harris RP Verheye HM Joly P Runge J Starr M Pond D Campbell R Shreeve R Ward P Smith AN Dam HG Peterson W Tirelli V Koski M Smith T Harbour D Davidson R 《Nature》2002,419(6905):387-389
Diatoms dominate spring bloom phytoplankton assemblages in temperate waters and coastal upwelling regions of the global ocean. Copepods usually dominate the zooplankton in these regions and are the prey of many larval fish species. Recent laboratory studies suggest that diatoms may have a deleterious effect on the success of copepod egg hatching. These findings challenge the classical view of marine food-web energy flow from diatoms to fish by means of copepods. Egg mortality is an important factor in copepod population dynamics, thus, if diatoms have a deleterious in situ effect, paradoxically, high diatom abundance could limit secondary production. Therefore, the current understanding of energy transfer from primary production to fisheries in some of the most productive and economically important marine ecosystems may be seriously flawed. Here we present in situ estimates of copepod egg hatching success from twelve globally distributed areas, where diatoms dominate the phytoplankton assemblage. We did not observe a negative relationship between copepod egg hatching success and either diatom biomass or dominance in the microplankton in any of these regions. The classical model for diatom-dominated system remains valid. 相似文献
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Auwerx J Avner P Baldock R Ballabio A Balling R Barbacid M Berns A Bradley A Brown S Carmeliet P Chambon P Cox R Davidson D Davies K Duboule D Forejt J Granucci F Hastie N de Angelis MH Jackson I Kioussis D Kollias G Lathrop M Lendahl U Malumbres M von Melchner H Müller W Partanen J Ricciardi-Castagnoli P Rigby P Rosen B Rosenthal N Skarnes B Stewart AF Thornton J Tocchini-Valentini G Wagner E Wahli W Wurst W 《Nature genetics》2004,36(9):925-927
The European Mouse Mutagenesis Consortium is the European initiative contributing to the international effort on functional annotation of the mouse genome. Its objectives are to establish and integrate mutagenesis platforms, gene expression resources, phenotyping units, storage and distribution centers and bioinformatics resources. The combined efforts will accelerate our understanding of gene function and of human health and disease. 相似文献
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Mira MT Alcaïs A Nguyen VT Moraes MO Di Flumeri C Vu HT Mai CP Nguyen TH Nguyen NB Pham XK Sarno EN Alter A Montpetit A Moraes ME Moraes JR Doré C Gallant CJ Lepage P Verner A Van De Vosse E Hudson TJ Abel L Schurr E 《Nature》2004,427(6975):636-640
Leprosy is caused by Mycobacterium leprae and affects about 700,000 individuals each year. It has long been thought that leprosy has a strong genetic component, and recently we mapped a leprosy susceptibility locus to chromosome 6 region q25-q26 (ref. 3). Here we investigate this region further by using a systematic association scan of the chromosomal interval most likely to harbour this leprosy susceptibility locus. In 197 Vietnamese families we found a significant association between leprosy and 17 markers located in a block of approx. 80 kilobases overlapping the 5' regulatory region shared by the Parkinson's disease gene PARK2 and the co-regulated gene PACRG. Possession of as few as two of the 17 risk alleles was highly predictive of leprosy. This was confirmed in a sample of 975 unrelated leprosy cases and controls from Brazil in whom the same alleles were strongly associated with leprosy. Variants in the regulatory region shared by PARK2 and PACRG therefore act as common risk factors for leprosy. 相似文献
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