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81.
Prevention of transgene flow from genetically modified crops to food crops and wild relatives is of concern in agricultural
biotechnology. We used genes derived from food crops to produce complete male sterility as a strategy for gene confinement
as well as to reduce the food purity concerns of consumers. Anther-specific promoters (A3, A6, A9, MS2, and MS5) were isolated from Brassica oleracea and B. rapa and fused to the β-glucuronidase (GUS) reporter gene and candidate genes for male sterility, including the cysteine proteases BoCysP1 and BoCP3, and negative regulatory components of phytohormonal responses involved in male development. These constructs were then introduced
into Arabidopsis thaliana. GUS analyses revealed that A3, A6, and A9 had tapetum-specific promoter activity from the anther meiocyte stage. Male sterility was confirmed in tested constructs
with protease or gibberellin insensitive (gai) genes. In particular, constructs with BoCysP1 driven by the A3 or A9 promoter most efficiently produced plants with complete male sterility. The tapetum and middle layer cells of anthers expressing
BoCysP1 were swollen and excessively vacuolated when observed in transverse section. This suggests that the ectopic expression of
cysteine protease in the meiocyte stage may inhibit programmed cell death. The gai gene also induced male sterility, although at a low frequency. This is the first report to show that plant cysteine proteases
and gai from food crops are available as a novel tool for the development of genetically engineered male-sterile plants.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
82.
Evaluation of the toxicity of stress-related aldehydes to photosynthesis in chloroplasts 总被引:1,自引:0,他引:1
Aldehydes produced under various environmental stresses can cause cellular injury in plants, but their toxicology in photosynthesis
has been scarcely investigated. We here evaluated their effects on photosynthetic reactions in chloroplasts isolated from
Spinacia oleracea L. leaves. Aldehydes that are known to stem from lipid peroxides inactivated the CO2 photoreduction to various extents, while their corresponding alcohols and carboxylic acids did not affect photosynthesis.
α,β-Unsaturated aldehydes (2-alkenals) showed greater inactivation than the saturated aliphatic aldehydes. The oxygenated short
aldehydes malondialdehyde, methylglyoxal, glycolaldehyde and glyceraldehyde showed only weak toxicity to photosynthesis. Among
tested 2-alkenals, 2-propenal (acrolein) was the most toxic, and then followed 4-hydroxy-(E)-2-nonenal and (E)-2-hexenal. While the CO2-photoreduction was inactivated, envelope intactness and photosynthetic electron transport activity (H2O → ferredoxin) were only slightly affected. In the acrolein-treated chloroplasts, the Calvin cycle enzymes phosphoribulokinase,
glyceraldehyde-3-phosphate dehydrogenase, fructose-1,6-bisphophatase, sedoheptulose-1,7-bisphosphatase, aldolase, and Rubisco
were irreversibly inactivated. Acrolein treatment caused a rapid drop of the glutathione pool, prior to the inactivation of
photosynthesis. GSH exogenously added to chloroplasts suppressed the acrolein-induced inactivation of photosynthesis, but
ascorbic acid did not show such a protective effect. Thus, lipid peroxide-derived 2-alkenals can inhibit photosynthesis by
depleting GSH in chloroplasts and then inactivating multiple enzymes in the Calvin cycle. 相似文献
83.
Akimitsu Miyaji Masashi Suzuki Toshihide Baba Toshiaki Kamachi Ichiro Okura 《Journal of Molecular Catalysis .B, Enzymatic》2009,57(1-4):211-215
Particulate methane monooxygenase (pMMO), a copper-containing membrane protein, catalyzes methane hydroxylation under aerobic conditions. We found that the activity of pMMO was increased by catalase, implying that hydrogen peroxide (H2O2) is generated by pMMO with duroquinol, an electron donor for pMMO, and that the generated H2O2 inhibits pMMO activity. In addition, reversible inhibition of pMMO with H2O2 was observed upon treatment of pMMO with H2O2 followed by the addition of catalase, and H2O2 formation by pMMO with duroquinol was detected using a fluorescence probe. The redox behavior of type 2 copper in pMMO measured by the electron paramagnetic resonance revealed that H2O2 re-oxidizes the type 2 copper in pMMO reduced with duroquinol. 相似文献
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86.
Shuichi Jo Atsushi Kawaguchi Naoki Takizawa Yuko Morikawa Fumitaka Momose Kyosuke Nagata 《Microbes and infection / Institut Pasteur》2010,12(12-13):1079-1084
The genome of influenza type A virus consists of single-stranded RNAs of negative polarity. Progeny viral RNA (vRNA) replicated in the nucleus is nuclear-exported, and finally transported to the budding site beneath the plasma membrane. However, the precise process of the membrane targeting of vRNA is unclear, although viral proteins and cytoskeleton are thought to play roles. Here, we have visualized the translocation process of progeny vRNA using fluorescence in situ hybridization method. Our results provide an evidence of the involvement of vesicular trafficking in membrane targeting of progeny vRNA independent of that of viral membrane proteins. 相似文献
87.
Makiko Suto Hidekazu Tanaka Yasuhide Mochizuki Jun Mukai Hiroki Takada Fumitaka Soga Kumiko Dokuni Yutaka Hatani Keiko Hatazawa Hiroki Matsuzoe Hiroyuki Sano Hiroyuki Shimoura Junichi Ooka Kensuke Matsumoto Yushi Hirota Wataru Ogawa Ken-ichi Hirata 《Cardiovascular diabetology》2017,16(1):145
Background
Coexistence of left ventricular (LV) longitudinal myocardial systolic dysfunction with LV diastolic dysfunction could lead to heart failure with preserved ejection fraction (HFpEF). Diabetes mellitus (DM) is known as a significant factor associated with HFpEF. Although the mechanisms of DM-related LV myocardial injury are complex, it has been postulated that overweight contributes to the development of LV myocardial injury in type 2 diabetes mellitus (T2DM) patients. However, the precise impact of overweight on LV longitudinal myocardial systolic function in T2DM patients remains unclear.Methods
We studied 145 asymptomatic T2DM patients with preserved LV ejection fraction (LVEF) without coronary artery disease. LV longitudinal myocardial systolic function was assessed by global longitudinal strain (GLS), which was defined as the average peak strain of 18-segments obtained from standard apical views. Overweight was defined as body mass index (BMI) ≥ 25 kg/m2. Ninety age-, gender- and LVEF-matched healthy volunteers served as controls.Results
GLS of overweight T2DM patients was significantly lower than that of non-overweight patients (17.9 ± 2.4% vs. 18.9 ± 2.6%, p < 0.05), whereas GLS of both overweight and non-overweight controls was similar (19.8 ± 1.3% vs. 20.4 ± 2.1%, p = 0.38). Furthermore, multiple regression analysis revealed that for T2DM patients, BMI was the independent determinant parameters for GLS as well as LV mass index.Conclusions
Overweight has a greater effect on LV longitudinal myocardial systolic function in T2DM patients than on that in non-DM healthy subjects. Our finding further suggests that the strict control of overweight in T2DM patients may be associated with prevention of the development of HFpEF.88.
Kazuhiro Sato Fumitaka Abe Martin Mascher Georg Haberer Heidrun Gundlach Manuel Spannagl Kenta Shirasawa Sachiko Isobe 《DNA research》2021,28(3)
We have established a high-quality, chromosome-level genome assembly for the hexaploid common wheat cultivar ‘Fielder’, an American, soft, white, pastry-type wheat released in 1974 and known for its amenability to Agrobacterium tumefaciens-mediated transformation and genome editing. Accurate, long-read sequences were obtained using PacBio circular consensus sequencing with the HiFi approach. Sequence reads from 16 SMRT cells assembled using the hifiasm assembler produced assemblies with N50 greater than 20 Mb. We used the Omni-C chromosome conformation capture technique to order contigs into chromosome-level assemblies, resulting in 21 pseudomolecules with a cumulative size of 14.7 and 0.3 Gb of unanchored contigs. Mapping of published short reads from a transgenic wheat plant with an edited seed-dormancy gene, TaQsd1, identified four positions of transgene insertion into wheat chromosomes. Detection of guide RNA sequences in pseudomolecules provided candidates for off-target mutation induction. These results demonstrate the efficiency of chromosome-scale assembly using PacBio HiFi reads and their application in wheat genome-editing studies. 相似文献
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