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991.
992.
Z. Xu J. Zhou T. Ren H. Du H. Liu Y. Li C. Zhang 《Plant biology (Stuttgart, Germany)》2020,22(5):813-821
- Apocynum venetum L. is a traditional Chinese medicinal herb with great potential to treat angiocardiopathy. Its major medicinal constituents are flavonoids. However, the natural habitats of A. venetum are typically affected by salt stress, which can modify both biomass and accumulation of medicinal compounds.
- In this study, the effects of salt stress on growth and development of A. venetum, accumulation of flavonoids and expression patterns of genes involved in flavonoid biosynthesis were evaluated.
- In general, the growth and development of seedlings (seedling height, root length, leaf length, leaf width and seed germination) were inhibited by salt stress. Unlike typical halophytes, there was no optimal NaCl concentration range that promoted growth and development, but seedlings had an elevated DW/FW ratio under salt stress (induced by irrigation with 50, 100, 200 or 400 mm NaCl). Furthermore, quercetin and kaempferol were significantly accumulated in A. venetum seedlings under salt stress, resulting in a balanced content and reduced FW. Moreover, the expression of AvCHS, AvCHI and AvF3GT was inhibited by salt stress; however, AvF3’H, AvF3H and AvFLS, which are involved in the flavonol synthesis pathway, were up‐regulated under salt stress, consistent with a decrease in total flavonoids and an increase of flavonols (quercetin and kaempferol).
- In summary, cultivation of A. venetum in saline soils appeared to be feasible and improved the medicinal quality of A. venetum (quercetin and kaempferol accumulation under salt stress), thus this species can effectively utilize saline soil resources.
993.
《Biochimica et Biophysica Acta - Proteins and Proteomics》2022,1870(8):140816
Senile plaques that is characterized as an amyloid deposition found in Alzheimer's disease are composed primarily of fibrils of an aggregated peptide, amyloid β (Aβ). The ability to monitor senile plaque formation on a neuronal membrane under physiological conditions provides an attractive model. In this study, the growth behavior of amyloid Aβ fibrils in the presence of liposomes incorporating β-cholesteryl-D-glucose (β-CG) was examined using total internal reflection fluorescence microscopy, transmittance electron microscopy, and other spectroscopic methods. We found that β-CG on the liposome membrane induced the spontaneous formation of spherulitic Aβ fibrillar aggregates. The β-CG cluster formed on liposome membranes appeared to induce the accumulation of Aβ, followed by the growth of the spherulitic Aβ aggregates. In contrast, DMPC and DMPC incorporated cholesterol-induced fibrils that are laterally associated with each other. A comparison study using three types of liposomes implied that the induction of glucose contributed to the agglomeration of Aβ fibrils and liposomes. This agglomeration required the spontaneous formation of spherulitic Aβ fibrillary aggregates. This action can be regarded as a counterbalance to the growth of fibrils and their toxicity, which has great potential in the study of amyloidopathies. 相似文献
994.
B. Emmanuel T.W. Fenton B.V. Turner L.P. Milligan 《Journal of biochemical and biophysical methods》1983,8(1):1-7
Total plama cholesterol concentration and radioactivity were measured simultaneously using a gas chromatograph equipped with a flame ionization detector and an effluent splitter. More than 99% of the recovered radioactivity was in the cholesterol peak. Specific activities were highly correlated with the amounts of labeled cholesterol present in plasma. The recovery of label was quantitative over a wide range of carrier cholesterol concentration. The method is highly reproducible, accurate, rapid and specific. 相似文献
995.
《Molecular & cellular proteomics : MCP》2022,21(11):100423
Organisms have developed different mechanisms to respond to stresses. However, the roles of small ORF–encoded peptides (SEPs) in these regulatory systems remain elusive, which is partially because of the lack of comprehensive knowledge regarding these biomolecules. We chose the extremophile Deinococcus radiodurans R1 as a model species and conducted large-scale profiling of the SEPs related to the stress response. The integrated workflow consisting of multiple omics approaches for SEP identification was streamlined, and an SEPome of D. radiodurans containing 109 novel and high-confidence SEPs was drafted. Forty-four percent of these SEPs were predicted to function as antimicrobial peptides. Quantitative peptidomics analysis indicated that the expression of SEP068184 was upregulated upon oxidative treatment and gamma irradiation of the bacteria. SEP068184 was conserved in Deinococcus and exhibited negative regulation of oxidative stress resistance in a comparative phenotypic assay of its mutants. Further quantitative and interactive proteomics analyses suggested that SEP068184 might function through metabolic pathways and interact with cytoplasmic proteins. Collectively, our findings demonstrate that SEPs are involved in the regulation of oxidative resistance, and the SEPome dataset provides a rich resource for research on the molecular mechanisms of the response to extreme stress in organisms. 相似文献
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999.
In-situ artificial stream channels and ex-situ laboratory mesocosms were used to measure the responses of macroinvertebrate
assemblages, from upland and lowland tropical streams, to high loads of fine clay sediment. Significant responses were observed
mainly in the in-situ channels in the upland stream, where densities and the number of taxa were lower in the treatment channels
than in controls. There was no evidence of any taxon being particularly sensitive to sedimentation, with a general decrease
in densities across several taxa and differences only detectable for abundant taxa. Animals moved downstream in response to
the treatment, but only a short distance within the channels. However, further colonization after the treatment was impeded
in the treatment channels. In the mesocosm experiments, the upland macroinvertebrate assemblage demonstrated some negative
effects; however, the lowland fauna was very tolerant to sedimentation, even when exposure was extended to 15 days. Together,
the mesocosm and in-situ experiments indicate that there is a behavioural response to sedimentation because of a change in
the habitat, and that the lowland macroinvertebrate assemblage is more tolerant of sedimentation, at least in the short term.
Handling editor: D. M. Harper 相似文献
1000.
Zhukov A. V. Lebedeva N. I. Vereshchagin A. G. 《Russian Journal of Plant Physiology》2001,48(1):111-115
The concentration of dry matter and the content of esterified fatty acids in total lipids of roots and etiolated shoots of 3- to 10-day-old seedlings of wheat (Triticum aestivum L.) infected with Bipolaris sorokiniana (Sacc.) Schoemaker, the agent of helminthosporic root rot, were determined in the course of germination. At the onset of germination, fungal infection caused a considerable increase in the dry matter concentration in both roots and shoots due to the enhanced mobilization of seed reserves. However, after the 7th day of germination, dry matter concentration fell below the level of noninfected control seedlings as a result of infection. The content of total lipids rose immediately after infection and always exceeded the control index up to the end of germination, in spite of a continuous decrease in this index in both control and infected seedling. It is concluded that an increase in the content of cellular lipids is a characteristic response of both shoots and roots to the root rot infection of wheat seedlings. 相似文献