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排序方式: 共有287条查询结果,搜索用时 15 毫秒
81.
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
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Nephrocystin-5, a ciliary IQ domain protein, is mutated in Senior-Loken syndrome and interacts with RPGR and calmodulin 总被引:14,自引:0,他引:14
Otto EA Loeys B Khanna H Hellemans J Sudbrak R Fan S Muerb U O'Toole JF Helou J Attanasio M Utsch B Sayer JA Lillo C Jimeno D Coucke P De Paepe A Reinhardt R Klages S Tsuda M Kawakami I Kusakabe T Omran H Imm A Tippens M Raymond PA Hill J Beales P He S Kispert A Margolis B Williams DS Swaroop A Hildebrandt F 《Nature genetics》2005,37(3):282-288
Nephronophthisis (NPHP) is the most frequent genetic cause of chronic renal failure in children. Identification of four genes mutated in NPHP subtypes 1-4 (refs. 4-9) has linked the pathogenesis of NPHP to ciliary functions. Ten percent of affected individuals have retinitis pigmentosa, constituting the renal-retinal Senior-Loken syndrome (SLSN). Here we identify, by positional cloning, mutations in an evolutionarily conserved gene, IQCB1 (also called NPHP5), as the most frequent cause of SLSN. IQCB1 encodes an IQ-domain protein, nephrocystin-5. All individuals with IQCB1 mutations have retinitis pigmentosa. Hence, we examined the interaction of nephrocystin-5 with RPGR (retinitis pigmentosa GTPase regulator), which is expressed in photoreceptor cilia and associated with 10-20% of retinitis pigmentosa. We show that nephrocystin-5, RPGR and calmodulin can be coimmunoprecipitated from retinal extracts, and that these proteins localize to connecting cilia of photoreceptors and to primary cilia of renal epithelial cells. Our studies emphasize the central role of ciliary dysfunction in the pathogenesis of SLSN. 相似文献
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Steffens S Veillard NR Arnaud C Pelli G Burger F Staub C Karsak M Zimmer A Frossard JL Mach F 《Nature》2005,434(7034):782-786
Atherosclerosis is a chronic inflammatory disease, and is the primary cause of heart disease and stroke in Western countries. Derivatives of cannabinoids such as delta-9-tetrahydrocannabinol (THC) modulate immune functions and therefore have potential for the treatment of inflammatory diseases. We investigated the effects of THC in a murine model of established atherosclerosis. Oral administration of THC (1 mg kg(-1) per day) resulted in significant inhibition of disease progression. This effective dose is lower than the dose usually associated with psychotropic effects of THC. Furthermore, we detected the CB2 receptor (the main cannabinoid receptor expressed on immune cells) in both human and mouse atherosclerotic plaques. Lymphoid cells isolated from THC-treated mice showed diminished proliferation capacity and decreased interferon-gamma secretion. Macrophage chemotaxis, which is a crucial step for the development of atherosclerosis, was also inhibited in vitro by THC. All these effects were completely blocked by a specific CB2 receptor antagonist. Our data demonstrate that oral treatment with a low dose of THC inhibits atherosclerosis progression in the apolipoprotein E knockout mouse model, through pleiotropic immunomodulatory effects on lymphoid and myeloid cells. Thus, THC or cannabinoids with activity at the CB2 receptor may be valuable targets for treating atherosclerosis. 相似文献
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Jung A Maier R Vartanian JP Bocharov G Jung V Fischer U Meese E Wain-Hobson S Meyerhans A 《Nature》2002,418(6894):144
The genome of the human immunodeficiency virus is highly prone to recombination, although it is not obvious whether recombinants arise infrequently or whether they are constantly being spawned but escape identification because of the massive and rapid turnover of virus particles. Here we use fluorescence in situ hybridization to estimate the number of proviruses harboured by individual splenocytes from two HIV patients, and determine the extent of recombination by sequencing amplified DNA from these cells. We find an average of three or four proviruses per cell and evidence for huge numbers of recombinants and extensive genetic variation. Although this creates problems for phylogenetic analyses, which ignore recombination effects, the intracellular variation may help to broaden immune recognition. 相似文献
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张述文 《兰州大学学报(自然科学版)》2000,36(6):112-117
给出了大气中二氧化碳浓度加倍引起的德国南部及邻近阿尔卑斯山区5年1月和 7月气温和降水率变化的模拟结果.模式采用在大气环流模式(ECHAM3)中嵌套的中尺度气候和化学模式(MCCM).模拟结果显示:区域平均气温(地面上2 m处温度)的5年平均1月增加0.8℃,7月增加4.7℃;区域降水率的5年逐月平均则显示1月无变化,7月减少40 %.讨论了气温、降水率以及降水频率等变化的空间分布,也给出了控制试验(1×CO2) 和敏感试验(2×CO2)中气温和降水率的年际变化模拟结果. 相似文献
90.
给出了大气中二氧化碳浓度加倍引起的德国南部及邻近阿尔卑斯山区5年1月和 7月气温和降水率变化的模拟结果.模式采用在大气环流模式(ECHAM3)中嵌套的中尺度气候 和化学模式(MCCM).模拟结果显示:区域平均气温(地面上2 m处温度)的5年平均1月增 加0.8℃,7月增加4.7℃;区域降水率的5年逐月平均则显示1月无变化,7月减少40 %.讨论了气温、降水率以及降水频率等变化的空间分布,也给出了控制试验(1×CO2) 和敏感试验(2×CO2)中气温和降水率的年际变化模拟结果. 相似文献