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Léveillard T Mohand-Saïd S Lorentz O Hicks D Fintz AC Clérin E Simonutti M Forster V Cavusoglu N Chalmel F Dollé P Poch O Lambrou G Sahel JA 《Nature genetics》2004,36(7):755-759
Retinitis pigmentosa is an untreatable, inherited retinal disease that leads to blindness. The disease initiates with the loss of night vision due to rod photoreceptor degeneration, followed by irreversible, progressive loss of cone photoreceptor. Cone loss is responsible for the main visual handicap, as cones are essential for day and high-acuity vision. Their loss is indirect, as most genes associated with retinitis pigmentosa are not expressed by these cells. We previously showed that factors secreted from rods are essential for cone viability. Here we identified one such trophic factor by expression cloning and named it rod-derived cone viability factor (RdCVF). RdCVF is a truncated thioredoxin-like protein specifically expressed by photoreceptors. The identification of this protein offers new treatment possibilities for retinitis pigmentosa. 相似文献
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The knockout mouse project 总被引:1,自引:0,他引:1
Austin CP Battey JF Bradley A Bucan M Capecchi M Collins FS Dove WF Duyk G Dymecki S Eppig JT Grieder FB Heintz N Hicks G Insel TR Joyner A Koller BH Lloyd KC Magnuson T Moore MW Nagy A Pollock JD Roses AD Sands AT Seed B Skarnes WC Snoddy J Soriano P Stewart DJ Stewart F Stillman B Varmus H Varticovski L Verma IM Vogt TF von Melchner H Witkowski J Woychik RP Wurst W Yancopoulos GD Young SG Zambrowicz B 《Nature genetics》2004,36(9):921-924
Mouse knockout technology provides a powerful means of elucidating gene function in vivo, and a publicly available genome-wide collection of mouse knockouts would be significantly enabling for biomedical discovery. To date, published knockouts exist for only about 10% of mouse genes. Furthermore, many of these are limited in utility because they have not been made or phenotyped in standardized ways, and many are not freely available to researchers. It is time to harness new technologies and efficiencies of production to mount a high-throughput international effort to produce and phenotype knockouts for all mouse genes, and place these resources into the public domain. 相似文献
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Sexual reproduction in many angiosperm plants involves self-incompatibility (SI), which is one of the most important mechanisms to prevent inbreeding. SI is genetically controlled by the S-locus, and involves highly specific interactions during pollination between pollen and the pistil on which it lands. This results in the rejection of incompatible ('self') pollen, whereas compatible ('non-self') pollen is allowed to fertilize the plant. In Papaver rhoeas, S-proteins encoded by the stigma component of the S-locus interact with incompatible pollen, triggering a Ca2+-dependent signalling network, resulting in the inhibition of pollen-tube growth. Programmed cell death (PCD) is a mechanism used by many organisms to destroy unwanted cells in a precisely regulated manner. Here we show that PCD is triggered by SI in an S-specific manner in incompatible pollen. This provides a demonstration of a SI system using PCD, revealing a novel mechanism to prevent self-fertilization. Furthermore, our data reveal that the response is biphasic; rapid inhibition of pollen-tube growth is followed by PCD, which is involved in a later 'decision-making' phase, making inhibition irreversible. 相似文献
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Instrumental observations and reconstructions of global and hemispheric temperature evolution reveal a pronounced warming during the past approximately 150 years. One expression of this warming is the observed increase in the occurrence of heatwaves. Conceptually this increase is understood as a shift of the statistical distribution towards warmer temperatures, while changes in the width of the distribution are often considered small. Here we show that this framework fails to explain the record-breaking central European summer temperatures in 2003, although it is consistent with observations from previous years. We find that an event like that of summer 2003 is statistically extremely unlikely, even when the observed warming is taken into account. We propose that a regime with an increased variability of temperatures (in addition to increases in mean temperature) may be able to account for summer 2003. To test this proposal, we simulate possible future European climate with a regional climate model in a scenario with increased atmospheric greenhouse-gas concentrations, and find that temperature variability increases by up to 100%, with maximum changes in central and eastern Europe. 相似文献
227.
Felis T Lohmann G Kuhnert H Lorenz SJ Scholz D Pätzold J Al-Rousan SA Al-Moghrabi SM 《Nature》2004,429(6988):164-168
The last interglacial period (about 125,000 years ago) is thought to have been at least as warm as the present climate. Owing to changes in the Earth's orbit around the Sun, it is thought that insolation in the Northern Hemisphere varied more strongly than today on seasonal timescales, which would have led to corresponding changes in the seasonal temperature cycle. Here we present seasonally resolved proxy records using corals from the northernmost Red Sea, which record climate during the last interglacial period, the late Holocene epoch and the present. We find an increased seasonality in the temperature recorded in the last interglacial coral. Today, climate in the northern Red Sea is sensitive to the North Atlantic Oscillation, a climate oscillation that strongly influences winter temperatures and precipitation in the North Atlantic region. From our coral records and simulations with a coupled atmosphere-ocean circulation model, we conclude that a tendency towards the high-index state of the North Atlantic Oscillation during the last interglacial period, which is consistent with European proxy records, contributed to the larger amplitude of the seasonal cycle in the Middle East. 相似文献
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