DUBA: a deubiquitinase that regulates type I interferon production     

Kayagaki N  Phung Q  Chan S  Chaudhari R  Quan C  O'Rourke KM  Eby M  Pietras E  Cheng G  Bazan JF  Zhang Z  Arnott D  Dixit VM 《Science (New York, N.Y.)》2007,318(5856):1628-1632

Production of type I interferon (IFN-I) is a critical host defense triggered by pattern-recognition receptors (PRRs) of the innate immune system. Deubiquitinating enzyme A (DUBA), an ovarian tumor domain-containing deubiquitinating enzyme, was discovered in a small interfering RNA-based screen as a regulator of IFN-I production. Reduction of DUBA augmented the PRR-induced IFN-I response, whereas ectopic expression of DUBA had the converse effect. DUBA bound tumor necrosis factor receptor-associated factor 3 (TRAF3), an adaptor protein essential for the IFN-I response. TRAF3 is an E3 ubiquitin ligase that preferentially assembled lysine-63-linked polyubiquitin chains. DUBA selectively cleaved the lysine-63-linked polyubiquitin chains on TRAF3, resulting in its dissociation from the downstream signaling complex containing TANK-binding kinase 1. A discrete ubiquitin interaction motif within DUBA was required for efficient deubiquitination of TRAF3 and optimal suppression of IFN-I. Our data identify DUBA as a negative regulator of innate immune responses.  相似文献   

Magnetic resonance studies of lunar samples     

Manatt SL  Elleman DD  Vaughan RW  Chan SI  Tsay FD  Huntress WT 《Science (New York, N.Y.)》1970,167(3918):709-711

Electron spin resonance searches at 9.5 gigahertz on several fines samples and portions of several rocks have yielded signals whose lineshapes and temperature dependences show that the samples are principally ferromagnetic in nature. Proton magnetic resonance searches at 60 megahertz of these samples have not revealed any signals ascribable to water or any other types of hydrogen in concentrations greater than 0.0001 percent by weight contained in narrow lines (5 oersteds wide or less) and 0.01 percent by weight in wide lines (as wide as 100 oersteds).  相似文献   

包头市全巴图工业污染区盐渍土特征研究   总被引：2，自引：0，他引：2  

张恭  杨茂 《内蒙古林学院学报》1997,19(2):1-7

包头市西南全巴图工业污水排放地区,在水文地质、气候等因素综合作用下,形成以草甸盐土为主的盐渍土,土壤中含盐量0.32～19.02％,是中度-强度盐渍化土或盐土,盐害较重,在进行改良后才能利用。盐土盐分以表层最高,土层中下部浓度变低,尤其改良地淡化过程明显(表3)。在本区盐渍土地上,采取合理的改良措施后,可以逐步地进行防污林带营造等保护生态环境的工程。  相似文献   

Emergence of anoxia in the California current large marine ecosystem     

Chan F  Barth JA  Lubchenco J  Kirincich A  Weeks H  Peterson WT  Menge BA 《Science (New York, N.Y.)》2008,319(5865):920

Eastern boundary current systems are among the world's most productive large marine ecosystems. Because upwelling currents transport nutrient-rich but oxygen-depleted water onto shallow seas, large expanses of productive continental shelves can be vulnerable to the risk of extreme low-oxygen events. Here, we report the novel rise of water-column shelf anoxia in the northern California Current system, a large marine ecosystem with no previous record of such extreme oxygen deficits. The expansion of anoxia highlights the potential for rapid and discontinuous ecosystem change in productive coastal systems that sustain a major portion of the world's fisheries.  相似文献   

不同氮素水平下生菜累积硝酸盐能力的品种差异分析     

侯迷红  王春枝  王婵  郭世乾  李瑛 《勤云标准版测试》2005,(5)

利用盆栽试验研究了生菜3个不同品种(苦苣、大速生、油麦)在不同氮素供应水平(0、0.2、0.4、0.6gN/kg土)下硝酸盐累积能力的差异。研究结果表明:同一氮肥水平下不同品种生菜硝酸盐含量和硝酸还原酶活性均存在显著性差异;在不同氮肥水平下,生菜各个品种硝酸盐含量具有显著差异性,且随氮肥水平的升高,其硝酸盐含量、硝酸还原酶活性呈递增趋势。因此,实际生产中选择降低硝酸盐措施时应将降低氮肥施用量及筛选低硝酸盐含量品种同时加以考虑。  相似文献   

Prevention of organ allograft rejection by a specific Janus kinase 3 inhibitor     

Changelian PS  Flanagan ME  Ball DJ  Kent CR  Magnuson KS  Martin WH  Rizzuti BJ  Sawyer PS  Perry BD  Brissette WH  McCurdy SP  Kudlacz EM  Conklyn MJ  Elliott EA  Koslov ER  Fisher MB  Strelevitz TJ  Yoon K  Whipple DA  Sun J  Munchhof MJ  Doty JL  Casavant JM  Blumenkopf TA  Hines M  Brown MF  Lillie BM  Subramanyam C  Shang-Poa C  Milici AJ  Beckius GE  Moyer JD  Su C  Woodworth TG  Gaweco AS  Beals CR  Littman BH  Fisher DA  Smith JF  Zagouras P  Magna HA  Saltarelli MJ  Johnson KS  Nelms LF  Des Etages SG  Hayes LS  Kawabata TT 《Science (New York, N.Y.)》2003,302(5646):875-878

Because of its requirement for signaling by multiple cytokines, Janus kinase 3 (JAK3) is an excellent target for clinical immunosuppression. We report the development of a specific, orally active inhibitor of JAK3, CP-690,550, that significantly prolonged survival in a murine model of heart transplantation and in cynomolgus monkeys receiving kidney transplants. CP-690,550 treatment was not associated with hypertension, hyperlipidemia, or lymphoproliferative disease. On the basis of these preclinical results, we believe JAK3 blockade by CP-690,550 has potential for therapeutically desirable immunosuppression in human organ transplantation and in other clinical settings.  相似文献   

Single crystal metals encapsulated in carbon nanoparticles     

Ruoff RS  Lorents DC  Chan B  Malhotra R  Subramoney S 《Science (New York, N.Y.)》1993,259(5093):346-348

Single-domain microcrystals of LaC(2) encapsulated within nanoscale polyhedral carbon particles have been synthesized in a carbon arc. Typical particle sizes are on the order of 20 to 40 nanometers. The stoichiometry and phase of the La-containing crystals have been assigned from characteristic lattice spacings observed by high-resolution transmission electron microscopy and energy dispersive spectroscopy (EDS). EDS spectra show that La and C are the only elements present. Characteristic interatomic distances of 3.39 and 2.78 angstroms identify the compound inside the nanoparticle cavities as alpha-LaC(2), the phase of LaC(2) that is stable at room temperature. Bulk alpha-LaC(2) is metallic and hydrolytic. Observation of crystals of pure encapsulated alpha-LaC(2) that were exposed to air for several days before analysis indicates that the LaC(2) is protected from degradation bythe carbon polyhedral shells of the nanoparticles. A high percentage of the carbon nanoparticles have encapsulated LaC(2) single crystals. These carbon-coated metal crystals form a new class of materials that can be protected in their pure or carbide forms and may have interesting and useful properties.  相似文献   

Observation of superflow in solid helium     

Kim E  Chan MH 《Science (New York, N.Y.)》2004,305(5692):1941-1944

We report on the observation of nonclassical rotational inertia in solid helium-4 confined to an annular channel in a sample cell under torsional motion, demonstrating superfluid behavior. The effect shows up as a drop in the resonant oscillation period as the sample cell is cooled below 230 millikelvin. Measurement of 17 solid samples allows us to map out the boundary of this superfluid-like solid or supersolid phase from the melting line up to 66 bars. This experiment indicates that superfluid behavior is found in all three phases of matter.  相似文献   

RNA silencing genes control de novo DNA methylation   总被引：1，自引：0，他引：1  

Chan SW  Zilberman D  Xie Z  Johansen LK  Carrington JC  Jacobsen SE 《Science (New York, N.Y.)》2004,303(5662):1336

  相似文献   

Error Sources on Yield-Based Fertilizer Variable Rate Application Maps     

Chan  C. W.  Schueller  J. K.  Miller  W. M.  Whitney  J. D.  Wheaton  T. A.  Cornell  J. A. 《Precision Agriculture》2002,3(1):81-94

Spatially-variable application of inputs to agricultural fields is dependent upon accuracy of the input variables. The effects of boundary determination, interpolation method, and GPS location errors were studied for determining a variable rate nitrogen application map based upon yield maps of a 3.6 ha Florida citrus block. A general linear model for the mean absolute error approximated the error effects.  相似文献