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排序方式: 共有117条查询结果,搜索用时 15 毫秒
111.
Summary InCulex pipiens mosquitos from Southern France, resistance to the organophosphorus insecticide chlorpyrifos is due to the dominant allele (Chl
R) of an autosomal gene. TheChl gene is localized between thea-Gpd andEst-2 loci at 26.8 and 5.8 units of crossing-over respectively. 相似文献
112.
Perlecan, the major proteoglycan of basement membranes, is altered in patients with Schwartz-Jampel syndrome (chondrodystrophic myotonia) 总被引:5,自引:0,他引:5
Nicole S Davoine CS Topaloglu H Cattolico L Barral D Beighton P Hamida CB Hammouda H Cruaud C White PS Samson D Urtizberea JA Lehmann-Horn F Weissenbach J Hentati F Fontaine B 《Nature genetics》2000,26(4):480-483
Schwartz-Jampel syndrome (SJS1) is a rare autosomal recessive disorder characterized by permanent myotonia (prolonged failure of muscle relaxation) and skeletal dysplasia, resulting in reduced stature, kyphoscoliosis, bowing of the diaphyses and irregular epiphyses. Electromyographic investigations reveal repetitive muscle discharges, which may originate from both neurogenic and myogenic alterations. We previously localized the SJS1 locus to chromosome 1p34-p36.1 and found no evidence of genetic heterogeneity. Here we describe mutations, including missense and splicing mutations, of the gene encoding perlecan (HSPG2) in three SJS1 families. In so doing, we have identified the first human mutations in HSPG2, which underscore the importance of perlecan not only in maintaining cartilage integrity but also in regulating muscle excitability. 相似文献
113.
114.
Hydrogen is an energy source for hydrothermal vent symbioses 总被引:1,自引:0,他引:1
Petersen JM Zielinski FU Pape T Seifert R Moraru C Amann R Hourdez S Girguis PR Wankel SD Barbe V Pelletier E Fink D Borowski C Bach W Dubilier N 《Nature》2011,476(7359):176-180
The discovery of deep-sea hydrothermal vents in 1977 revolutionized our understanding of the energy sources that fuel primary productivity on Earth. Hydrothermal vent ecosystems are dominated by animals that live in symbiosis with chemosynthetic bacteria. So far, only two energy sources have been shown to power chemosynthetic symbioses: reduced sulphur compounds and methane. Using metagenome sequencing, single-gene fluorescence in situ hybridization, immunohistochemistry, shipboard incubations and in situ mass spectrometry, we show here that the symbionts of the hydrothermal vent mussel Bathymodiolus from the Mid-Atlantic Ridge use hydrogen to power primary production. In addition, we show that the symbionts of Bathymodiolus mussels from Pacific vents have hupL, the key gene for hydrogen oxidation. Furthermore, the symbionts of other vent animals such as the tubeworm Riftia pachyptila and the shrimp Rimicaris exoculata also have hupL. We propose that the ability to use hydrogen as an energy source is widespread in hydrothermal vent symbioses, particularly at sites where hydrogen is abundant. 相似文献
115.
Rosenzweig C Karoly D Vicarelli M Neofotis P Wu Q Casassa G Menzel A Root TL Estrella N Seguin B Tryjanowski P Liu C Rawlins S Imeson A 《Nature》2008,453(7193):353-357
Significant changes in physical and biological systems are occurring on all continents and in most oceans, with a concentration of available data in Europe and North America. Most of these changes are in the direction expected with warming temperature. Here we show that these changes in natural systems since at least 1970 are occurring in regions of observed temperature increases, and that these temperature increases at continental scales cannot be explained by natural climate variations alone. Given the conclusions from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report that most of the observed increase in global average temperatures since the mid-twentieth century is very likely to be due to the observed increase in anthropogenic greenhouse gas concentrations, and furthermore that it is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent except Antarctica, we conclude that anthropogenic climate change is having a significant impact on physical and biological systems globally and in some continents. 相似文献
116.
Zody MC Garber M Adams DJ Sharpe T Harrow J Lupski JR Nicholson C Searle SM Wilming L Young SK Abouelleil A Allen NR Bi W Bloom T Borowsky ML Bugalter BE Butler J Chang JL Chen CK Cook A Corum B Cuomo CA de Jong PJ DeCaprio D Dewar K FitzGerald M Gilbert J Gibson R Gnerre S Goldstein S Grafham DV Grocock R Hafez N Hagopian DS Hart E Norman CH Humphray S Jaffe DB Jones M Kamal M Khodiyar VK LaButti K Laird G Lehoczky J Liu X Lokyitsang T Loveland J Lui A Macdonald P Major JE Matthews L Mauceli E 《Nature》2006,440(7087):1045-1049
Chromosome 17 is unusual among the human chromosomes in many respects. It is the largest human autosome with orthology to only a single mouse chromosome, mapping entirely to the distal half of mouse chromosome 11. Chromosome 17 is rich in protein-coding genes, having the second highest gene density in the genome. It is also enriched in segmental duplications, ranking third in density among the autosomes. Here we report a finished sequence for human chromosome 17, as well as a structural comparison with the finished sequence for mouse chromosome 11, the first finished mouse chromosome. Comparison of the orthologous regions reveals striking differences. In contrast to the typical pattern seen in mammalian evolution, the human sequence has undergone extensive intrachromosomal rearrangement, whereas the mouse sequence has been remarkably stable. Moreover, although the human sequence has a high density of segmental duplication, the mouse sequence has a very low density. Notably, these segmental duplications correspond closely to the sites of structural rearrangement, demonstrating a link between duplication and rearrangement. Examination of the main classes of duplicated segments provides insight into the dynamics underlying expansion of chromosome-specific, low-copy repeats in the human genome. 相似文献
117.
Woyke T Teeling H Ivanova NN Huntemann M Richter M Gloeckner FO Boffelli D Anderson IJ Barry KW Shapiro HJ Szeto E Kyrpides NC Mussmann M Amann R Bergin C Ruehland C Rubin EM Dubilier N 《Nature》2006,443(7114):950-955
Symbioses between bacteria and eukaryotes are ubiquitous, yet our understanding of the interactions driving these associations is hampered by our inability to cultivate most host-associated microbes. Here we use a metagenomic approach to describe four co-occurring symbionts from the marine oligochaete Olavius algarvensis, a worm lacking a mouth, gut and nephridia. Shotgun sequencing and metabolic pathway reconstruction revealed that the symbionts are sulphur-oxidizing and sulphate-reducing bacteria, all of which are capable of carbon fixation, thus providing the host with multiple sources of nutrition. Molecular evidence for the uptake and recycling of worm waste products by the symbionts suggests how the worm could eliminate its excretory system, an adaptation unique among annelid worms. We propose a model that describes how the versatile metabolism within this symbiotic consortium provides the host with an optimal energy supply as it shuttles between the upper oxic and lower anoxic coastal sediments that it inhabits. 相似文献