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31.
Qingyu Wu Toshiro Shigaki Jeung-Sul Han Chang Kil Kim Kendal D. Hirschi Sunghun Park 《Plant molecular biology》2012,80(6):609-619
Deregulated expression of an Arabidopsis H+/Ca2+ antiporter (sCAX1) in agricultural crops increases total calcium (Ca2+) but may result in yield losses due to Ca2+ deficiency-like symptoms. Here we demonstrate that co-expression of a maize calreticulin (CRT, a Ca2+ binding protein located at endoplasmic reticulum) in sCAX1-expressing tobacco and tomato plants mitigated these adverse effects while maintaining enhanced Ca2+ content. Co-expression of CRT and sCAX1 could alleviate the hypersensitivity to ion imbalance in tobacco plants. Furthermore, blossom-end rot (BER) in tomato may be linked to changes in CAX activity and enhanced CRT expression mitigated BER in sCAX1 expressing lines. These findings suggest that co-expressing Ca2+ transporters and binding proteins at different intracellular compartments can alter the content and distribution of Ca2+ within the plant matrix. 相似文献
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Hirschi KD 《Trends in plant science》2012,17(3):123-125
Recent findings show that genetic material in plant foods may survive digestion, circulate through our bodies and modulate our gene expression. These findings could alter our understanding of nutrition, genetic regulation and open up new vistas for engineering foods. 相似文献
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Hoppitt WJ Brown GR Kendal R Rendell L Thornton A Webster MM Laland KN 《Trends in ecology & evolution》2008,23(9):486-493
Many species are known to acquire valuable life skills and information from others, but until recently it was widely believed that animals did not actively facilitate learning in others. Teaching was regarded as a uniquely human faculty. However, recent studies suggest that teaching might be more common in animals than previously thought. Teaching is present in bees, ants, babblers, meerkats and other carnivores but is absent in chimpanzees, a bizarre taxonomic distribution that makes sense if teaching is treated as a form of altruism. Drawing on both mechanistic and functional arguments, we integrate teaching with the broader field of animal social learning, and show how this aids understanding of how and why teaching evolved, and the diversity of teaching mechanisms. 相似文献
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B. D. Hansen J. French K. A. Handasyde T. A. Kendal A. C. Taylor 《Molecular ecology resources》2003,3(2):212-214
The New Guinean endemic dactylopsilines are members of the Petauridae possum family, represented in Australia only by the striped possum Dactylopsila trivirgata. The shy nature and low density of this species have hampered studies of its ecology to date, so we developed nine highly variable polymorphic microsatellite markers to enable molecular genetic analysis of population structure and mating system parameters. This will add substantially to our understanding of the behavioural ecology of this species. The low degree of cross‐amplification of the primers in other petaurid species lends weight to other evidence suggesting that this family underwent a relatively early radiation. 相似文献
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Comparative Studies of Wild-Type and “Cold-Mutant” (Temperature-Sensitive) Influenza Viruses: Polypeptide Synthesis by an Asian (H2N2) Strain and Its Cold-Adapted Variant 下载免费PDF全文
The structure and replication of a cold-adapted, temperature-sensitive (TS) mutant of an Asian (H2N2) influenza virus was compared with that of its wild-type (WT) parent. Viruses were grown in a chicken kidney cell system, and at the nonpermissive temperature of 40 C, production of infectious TS virus was about 100,000-fold less than at 35 C, in contrast to WT virus. Major structural polypeptides of each virus grown at 35 C were similar, except that the hemagglutinin glycopolypeptide (HA) of the TS virions was slightly more heterogenous than that of WT virions. Synthesis of viral polypeptides was examined by sodium dodecyl sulfate acrylamide gel electrophoresis of pulse-labeled infected cells. This revealed a defect in the synthesis of TS viral hemagglutinin that was most pronounced at the nonpermissive temperature. Other TS viral polypeptides appeared to be synthesized normally at 40 C. A defect in the TS virus hemagglutinin was also indicated by serological studies that demonstrated that TS virus hemagglutinin had lost antigenic sites present on the WT virus. Thus, it is concluded that the virus mutant examined contains lesions in the hemagglutinin gene, although the possibility of additional unrecognized lesions is not excluded. 相似文献
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Hirschi K 《Trends in plant science》2008,13(9):459-463
Modern breeding, molecular genetic and biotechnology studies frequently describe changes in plant metabolism to improve nutritional content; however, this is often where the process of assessing biofortification ends. Ideally, these modified plants need to be used in controlled animal and human feeding studies to assess nutritional impact. Such bioavailability studies are crucial if any claims are to be made regarding health benefits and might be an important component in public acceptance of biofortified foods. 相似文献