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31.
Mats Ellerström Lars -Göran Josefsson Lars Rask Hans Ronne 《Plant molecular biology》1992,18(3):557-566
Both insect and mammalian genes have previously been cloned by genetic complementation in yeast. In the present report, we show that the method can be applied also to plants. Thus, we have cloned a rape cDNA for 3-isopropylmalate dehydrogenase (IMDH) by complementation of a yeast leu2 mutation. The cDNA encodes a 52 kDA protein which has a putative chloroplast transit peptide. The in vitro made protein is imported into chloroplasts, concomitantly with a proteolytic cleavage. We conclude that the rape cDNA encodes a chloroplast IMDH. However, Southern analysis revealed that the corresponding gene is nuclear. In a comparison of IMDH sequences from various species, we found that the rape IMDH is more similar to bacterial than to eukaryotic proteins. This suggests that the rape gene could be of chloroplast origin, but has moved to the nucleus during evolution. 相似文献
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Joel C. Trexler Joseph Travis Melanie Trexler 《Evolution; international journal of organic evolution》1990,44(1):157-167
Field studies indicate that the influence of environmental factors on growth rate and size and age at maturity in sailfin mollies (Poecilia latipinna) is inconsistent over time and suggest that the marked interdemic variation in male body size in this species is the result of genetic variation. However, the role of specific environmental factors in generating phenotypic variation must be studied under controlled conditions unattainable in nature. We raised newborn sailfin mollies from four populations in laboratory aquaria under all possible combinations of two temperatures, three salinities, and two food levels to examine explicitly the influence of these environmental factors. Males were much less susceptible than females to temperature variation and were generally less plastic than females in terms of all three traits. Members of both sexes matured at larger sizes and at later ages in less saline and in cooler environments. Food levels were not sufficiently different to affect the traits we studied. The effects of temperature and salinity were not synergistic. Males from different populations exhibited different average ages and sizes at maturity, but females did not. The magnitudes of the effects we found were not substantial enough to account for the consistent interdemic differences in male and female body size that have been observed previously. Our results also indicate that no single environmental factor is solely responsible for the environmental effects observed in field experiments on growth and development. These studies, together with other work, indicate that the strongest sources of interdemic variation are genetic differences in males and differences in postmaturation growth and survivorship in females. 相似文献
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Loree Heller Reynald Thinard Melanie Chevalier Sezgi Arpag Yu Jing Ruth Greferath Richard Heller Claude Nicolau 《Journal of cellular and molecular medicine》2020,24(15):8772-8778
In neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis and amyotrophic lateral sclerosis, neuroinflammation can lead to blood‐brain barrier (BBB) breakdown. After intravenous or intra‐arterial injection into mice, endothelial progenitor cells (EPCs) home to the damaged BBB to promote neurovascular repair. Autologous EPCs transfected to express specific therapeutic proteins offer an innovative therapeutic option. Here, we demonstrate that EPC transfection by electroporation with plasmids encoding the reporter protein GFP or an anti‐β‐amyloid antibody fragment (Fab) leads to secretion of each protein. We also demonstrate the secreted anti‐β‐amyloid Fab protein functions in β‐amyloid aggregate solubilization. 相似文献
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Schlacher Thomas A. Gilby Ben L. Olds Andrew D. Henderson Christopher J. Connolly Rod M. Peterson Charles H. Voss Christine M. Maslo Brooke Weston Michael A. Bishop Melanie J. Rowden Ashley 《Ecosystems》2020,23(4):906-916
Ecosystems - Ecotones can form hot spots of biodiversity by containing species from multiple ecosystems. Because biodiversity is often linked to ecological function, we posit that rates of key... 相似文献
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Murray Kimberley R. Bird Melanie Strack Maria Cody Michael Xu Bin 《Wetlands Ecology and Management》2021,29(2):281-299
Wetlands Ecology and Management - Oil sands exploration activities across the Alberta boreal peatlands requires tree clearing and results in sites being left compressed and with altered understory... 相似文献