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101.
Genomic sequence of the pathogenic and allergenic filamentous fungus Aspergillus fumigatus 总被引:1,自引:0,他引:1
Nierman WC Pain A Anderson MJ Wortman JR Kim HS Arroyo J Berriman M Abe K Archer DB Bermejo C Bennett J Bowyer P Chen D Collins M Coulsen R Davies R Dyer PS Farman M Fedorova N Fedorova N Feldblyum TV Fischer R Fosker N Fraser A García JL García MJ Goble A Goldman GH Gomi K Griffith-Jones S Gwilliam R Haas B Haas H Harris D Horiuchi H Huang J Humphray S Jiménez J Keller N Khouri H Kitamoto K Kobayashi T Konzack S Kulkarni R Kumagai T Lafon A Lafton A Latgé JP Li W Lord A Lu C Majoros WH May GS 《Nature》2005,438(7071):1151-1156
Aspergillus fumigatus is exceptional among microorganisms in being both a primary and opportunistic pathogen as well as a major allergen. Its conidia production is prolific, and so human respiratory tract exposure is almost constant. A. fumigatus is isolated from human habitats and vegetable compost heaps. In immunocompromised individuals, the incidence of invasive infection can be as high as 50% and the mortality rate is often about 50% (ref. 2). The interaction of A. fumigatus and other airborne fungi with the immune system is increasingly linked to severe asthma and sinusitis. Although the burden of invasive disease caused by A. fumigatus is substantial, the basic biology of the organism is mostly obscure. Here we show the complete 29.4-megabase genome sequence of the clinical isolate Af293, which consists of eight chromosomes containing 9,926 predicted genes. Microarray analysis revealed temperature-dependent expression of distinct sets of genes, as well as 700 A. fumigatus genes not present or significantly diverged in the closely related sexual species Neosartorya fischeri, many of which may have roles in the pathogenicity phenotype. The Af293 genome sequence provides an unparalleled resource for the future understanding of this remarkable fungus. 相似文献
102.
WUSCHEL controls meristem function by direct regulation of cytokinin-inducible response regulators 总被引:2,自引:0,他引:2
Leibfried A To JP Busch W Stehling S Kehle A Demar M Kieber JJ Lohmann JU 《Nature》2005,438(7071):1172-1175
103.
Dodge-Kafka KL Soughayer J Pare GC Carlisle Michel JJ Langeberg LK Kapiloff MS Scott JD 《Nature》2005,437(7058):574-578
Cyclic adenosine 3', 5'-monophosphate (cAMP) is a ubiquitous mediator of intracellular signalling events. It acts principally through stimulation of cAMP-dependent protein kinases (PKAs) but also activates certain ion channels and guanine nucleotide exchange factors (Epacs). Metabolism of cAMP is catalysed by phosphodiesterases (PDEs). Here we identify a cAMP-responsive signalling complex maintained by the muscle-specific A-kinase anchoring protein (mAKAP) that includes PKA, PDE4D3 and Epac1. These intermolecular interactions facilitate the dissemination of distinct cAMP signals through each effector protein. Anchored PKA stimulates PDE4D3 to reduce local cAMP concentrations, whereas an mAKAP-associated ERK5 kinase module suppresses PDE4D3. PDE4D3 also functions as an adaptor protein that recruits Epac1, an exchange factor for the small GTPase Rap1, to enable cAMP-dependent attenuation of ERK5. Pharmacological and molecular manipulations of the mAKAP complex show that anchored ERK5 can induce cardiomyocyte hypertrophy. Thus, two coupled cAMP-dependent feedback loops are coordinated within the context of the mAKAP complex, suggesting that local control of cAMP signalling by AKAP proteins is more intricate than previously appreciated. 相似文献
104.
Lin JF Struzhkin VV Jacobsen SD Hu MY Chow P Kung J Liu H Mao HK Hemley RJ 《Nature》2005,436(7049):377-380
Iron is the most abundant transition-metal element in the mantle and therefore plays an important role in the geochemistry and geodynamics of the Earth's interior. Pressure-induced electronic spin transitions of iron occur in magnesiowüstite, silicate perovskite and post-perovskite. Here we have studied the spin states of iron in magnesiowüstite and the isolated effects of the electronic transitions on the elasticity of magnesiowüstite with in situ X-ray emission spectroscopy and X-ray diffraction to pressures of the lowermost mantle. An observed high-spin to low-spin transition of iron in magnesiowüstite results in an abnormal compressional behaviour between the high-spin and the low-spin states. The high-pressure, low-spin state exhibits a much higher bulk modulus and bulk sound velocity than the low-pressure, high-spin state; the bulk modulus jumps by approximately 35 percent and bulk sound velocity increases by approximately 15 percent across the transition in (Mg0.83,Fe0.17)O. Although no significant density change is observed across the electronic transition, the jump in the sound velocities and the bulk modulus across the transition provides an additional explanation for the seismic wave heterogeneity in the lowermost mantle. The transition also affects current interpretations of the geophysical and geochemical models using extrapolated or calculated thermal equation-of-state data without considering the effects of the electronic transition. 相似文献
105.
Silk JB Brosnan SF Vonk J Henrich J Povinelli DJ Richardson AS Lambeth SP Mascaro J Schapiro SJ 《Nature》2005,437(7063):1357-1359
Humans are an unusually prosocial species-we vote, give blood, recycle, give tithes and punish violators of social norms. Experimental evidence indicates that people willingly incur costs to help strangers in anonymous one-shot interactions, and that altruistic behaviour is motivated, at least in part, by empathy and concern for the welfare of others (hereafter referred to as other-regarding preferences). In contrast, cooperative behaviour in non-human primates is mainly limited to kin and reciprocating partners, and is virtually never extended to unfamiliar individuals. Here we present experimental tests of the existence of other-regarding preferences in non-human primates, and show that chimpanzees (Pan troglodytes) do not take advantage of opportunities to deliver benefits to familiar individuals at no material cost to themselves, suggesting that chimpanzee behaviour is not motivated by other-regarding preferences. Chimpanzees are among the primates most likely to demonstrate prosocial behaviours. They participate in a variety of collective activities, including territorial patrols, coalitionary aggression, cooperative hunting, food sharing and joint mate guarding. Consolation of victims of aggression and anecdotal accounts of solicitous treatment of injured individuals suggest that chimpanzees may feel empathy. Chimpanzees sometimes reject exchanges in which they receive less valuable rewards than others, which may be one element of a 'sense of fairness', but there is no evidence that they are averse to interactions in which they benefit more than others. 相似文献
106.
Hornstein E Mansfield JH Yekta S Hu JK Harfe BD McManus MT Baskerville S Bartel DP Tabin CJ 《Nature》2005,438(7068):671-674
107.
Mice overexpressing human uncoupling protein-3 in skeletal muscle are hyperphagic and lean 总被引:30,自引:0,他引:30
Clapham JC Arch JR Chapman H Haynes A Lister C Moore GB Piercy V Carter SA Lehner I Smith SA Beeley LJ Godden RJ Herrity N Skehel M Changani KK Hockings PD Reid DG Squires SM Hatcher J Trail B Latcham J Rastan S Harper AJ Cadenas S Buckingham JA Brand MD Abuin A 《Nature》2000,406(6794):415-418
Uncoupling protein-3 (UCP-3) is a recently identified member of the mitochondrial transporter superfamily that is expressed predominantly in skeletal muscle. However, its close relative UCP-1 is expressed exclusively in brown adipose tissue, a tissue whose main function is fat combustion and thermogenesis. Studies on the expression of UCP-3 in animals and humans in different physiological situations support a role for UCP-3 in energy balance and lipid metabolism. However, direct evidence for these roles is lacking. Here we describe the creation of transgenic mice that overexpress human UCP-3 in skeletal muscle. These mice are hyperphagic but weigh less than their wild-type littermates. Magnetic resonance imaging shows a striking reduction in adipose tissue mass. The mice also exhibit lower fasting plasma glucose and insulin levels and an increased glucose clearance rate. This provides evidence that skeletal muscle UCP-3 has the potential to influence metabolic rate and glucose homeostasis in the whole animal. 相似文献
108.
P. K. Adhikary J. K. Haynes H. L. Patthey R. S. Rhodes 《Cellular and molecular life sciences : CMLS》1978,34(6):804-806
Summary 2-{benzoylamino} pyridinium benzoate (BAPB) has exhibited an antisickling effect with homozygous S/S erythrocytes in vitro. This study suggests that BAPB prevents sicklin by inhibiting the gelation of hemoglobin S.Acknowledgments. This research has been partly funded by a Sickle Cell Research grant from the State of Tennessee to Meharry Medical College. We gratefully appreciate the technical assistance of Mr Rudolf Harlan and Mrs Marjorie Deveau of the School of Graduate Studies. We offer our thanks to Dr J. W. Davis, J. D., Coordinator, Sickle Cell Project, Meharry Medical College for constant encouragement. 相似文献
109.
Zusammenfassung Neue Variante des Radio-Immundiffusionstests mit Antigenanalyse von menschlichem Gonadotrophin.
This work was supported by AEC Contract No. AT(11-1)2031 and NIH Grant No. HD-0068-12. 相似文献
This work was supported by AEC Contract No. AT(11-1)2031 and NIH Grant No. HD-0068-12. 相似文献
110.
The ability of killer T cells carrying the CD8 antigen to detect tumours or intracellular pathogens requires an extensive display of antigenic peptides by major histocompatibility complex (MHC) class I molecules on the surface of potential target cells. These peptides are derived from almost all intracellular proteins and reveal the presence of foreign pathogens and mutations. How cells produce thousands of distinct peptides cleaved to the precise lengths required for binding different MHC class I molecules remains unknown. The peptides are cleaved from endogenously synthesized proteins by the proteasome in the cytoplasm and then trimmed by an unknown aminopeptidase in the endoplasmic reticulum (ER). Here we identify ERAAP, the aminopeptidase associated with antigen processing in the ER. ERAAP has a broad substrate specificity, and its expression is strongly upregulated by interferon-gamma. Reducing the expression of ERAAP through RNA interference prevents the trimming of peptides for MHC class I molecules in the ER and greatly reduces the expression of MHC class I molecules on the cell surface. Thus, ERAAP is the missing link between the products of cytosolic processing and the final peptides presented by MHC class I molecules on the cell surface. 相似文献