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Solute carriers involved in energy transfer of mitochondria form a homologous protein family 总被引:11,自引:0,他引:11
The sequences of three mitochondrial carriers involved in energy transfer, the ADP/ATP carrier, phosphate carrier and uncoupling carrier, are analyzed. Similarly to what has been previously reported for the ADP/ATP carrier and the uncoupling protein, now also the phosphate carrier is found to have a tripartite structure comprising three similar repeats of approx. 100 residues each. The three sequences show a fair overall homology with each other. More significant homologies are found by comparing the repeats within and between the carriers in a scheme where the sequences are spliced into repeats, which are arranged for maximum homology by allowing possible insertions or deletions. A striking conservation of critical residues, glycine, proline, of charged and of aromatic residues is found throughout all nine repeats. This is indicative of a similar structural principle in the repeats. Hydropathy profiles of the three proteins and a search for amphipathic alpha-spans reveal six membrane-spanning segments for each carrier, providing further support for the basic structural identity of the repeats. The proposed folding pattern of the carriers in the membrane is exemplified with the phosphate carrier. A possible tertiary arrangement of the repeats and the membrane-spanning helices is shown. The emergence of a mitochondrial carrier family by triplication and by divergent evolution from a common gene of about 100 residues is discussed. 相似文献
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目的构建用于呼吸道合胞病毒(respiratory syncytial virus,RSV)体外拯救的RSV基因组全长cDNA克隆,并进行鉴定。方法根据RSV Long株基因组序列设计并合成引物,利用RT-PCR技术分6段扩增RSV LZ01/09基因组序列并构建克隆载体;测序后,利用重叠PCR与酶切连接技术,根据基因组序列选择特异性酶切位点,引入Kpn I、Xma I和Sal I酶切位点,构建成4个亚克隆载体;将亚克隆载体的插入片段连接至经过改造且包含T7启动子、锤头状核酶、多克隆位点、丁肝核酶、T7终止子的p RSV1载体中,构建RSV基因组全长cDNA克隆;对克隆全长cDNA序列进行测定,与亲本RSV LZ01/09基因组进行同源性比对分析,并与RSV实验参比株进行系统进化树分析。结果测序结果显示,RSV LZ 01/09的基因组全长为15 204 bp,与GenBank公布的RSV基因组序列长度相当,将完整的序列提交GenBank,登录号为KY782635;酶切及测序结果显示,用于RSV全长cDNA克隆构建的基本载体p BSKS-MCS(简称p RSV1)与预期相符,RSV全长基因组cDNA克隆质粒(简称转录载体p RSV1-4F)酶切片段大小与预期一致;同源性比对结果显示,全长cDNA序列与亲本RSV LZ01/09基因组序列同源性高达99.83%;系统进化树分析结果显示,其与RSV-A亚型序列同属于一个分支。结论测序及酶切分析结果表明已成功构建RSVLZ01/09基因组全长cDNA克隆,为建立拯救RSV重组病毒的反向遗传学系统平台奠定了基础。 相似文献
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Friedland KD Stock C Drinkwater KF Link JS Leaf RT Shank BV Rose JM Pilskaln CH Fogarty MJ 《PloS one》2012,7(1):e28945
The shift in marine resource management from a compartmentalized approach of dealing with resources on a species basis to an approach based on management of spatially defined ecosystems requires an accurate accounting of energy flow. The flow of energy from primary production through the food web will ultimately limit upper trophic-level fishery yields. In this work, we examine the relationship between yield and several metrics including net primary production, chlorophyll concentration, particle-export ratio, and the ratio of secondary to primary production. We also evaluate the relationship between yield and two additional rate measures that describe the export of energy from the pelagic food web, particle export flux and mesozooplankton productivity. We found primary production is a poor predictor of global fishery yields for a sample of 52 large marine ecosystems. However, chlorophyll concentration, particle-export ratio, and the ratio of secondary to primary production were positively associated with yields. The latter two measures provide greater mechanistic insight into factors controlling fishery production than chlorophyll concentration alone. Particle export flux and mesozooplankton productivity were also significantly related to yield on a global basis. Collectively, our analyses suggest that factors related to the export of energy from pelagic food webs are critical to defining patterns of fishery yields. Such trophic patterns are associated with temperature and latitude and hence greater yields are associated with colder, high latitude ecosystems. 相似文献
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L. Link 《Cell and tissue research》1962,56(2):143-148
Ohne Zusammenfassung 相似文献
700.
Guthrie S. Zimmerman John R. Sauer William A. Link Mark Otto 《The Journal of wildlife management》2012,76(6):1165-1176
Waterfowl are monitored in eastern Canada and the northeastern United States with 2 surveys: a transect survey from fixed-wing aircraft and a plot survey conducted from helicopters. The surveys vary in extent, but overlap exists in a core area of 9 strata covering portions of all provinces from Ontario east to Newfoundland. We estimated population change for American black ducks (Anas rubripes) and mallards (Anas platyrhynchos) from these surveys using a log-linear hierarchical model that accommodates differences in sample design and visibility associated with these survey methods. Using a combined analysis of the surveys based on total indicated birds, we estimate the American black duck population to be 901,700 (95% CI: 715,200–1,274,000) in 2011, with 526,900 (95% CI: 357,500–852,300) mallards in the surveyed area. Precision of estimates varies widely by species and region, with transect surveys providing less precise results than plot surveys for black ducks in areas of overlap. The combined survey analysis for black ducks in the eastern survey region produced estimates with an average yearly coefficient of variation (CV) of 12.1% for the entire area and an average CV of 6.9% in the plot survey area. Mallards, which had a more limited distribution in the region, had an average yearly CV of 22.1% over the entire region, and an average CV of 27.7% in the plot survey area. Hierarchical models provide a rich framework for analyzing and combining results from complex survey designs, providing useful spatial and temporal information on population size and change in these economically important species. © 2012 The Wildlife Society. 相似文献