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381.
The migration sources and pathways of Sogatella furcifera (Horváth) in topologically complex regions like Yunnan, China, and adjacent montane areas have long been a challenging task and a bottleneck in effective pest forecast and control. The present research reinvestigated this issue using a combination of mtDNA and long‐term historical wind field data in an attempt to provide new insights. Genetic analyses showed that the 60 populations of S. furcufera collected across Myanmar, Thailand, Laos, Vietnam, Yunnan, Guizhou, and Sichuan lack genetic structure and geographic isolation, while spatial analysis of haplotype and diversity indices discovered geographic relevance between populations. Migration rate analysis combined with high‐resolution 10‐year wind field analysis detected the following migration sources, pathways, and impacted areas which could explain the outbreak pattern in Yunnan. (a) Dominating stepwise northward migrations originated from northern Indochina, southern Yunnan, and central‐eastern Yunnan, impacting their northern areas. (b) Concurring summer–autumn southward (return) migration originated from nearly all latitude belts of Sichuan and Yunnan mainly impacting central and southern Yunnan. (c) Regular eastward and summer–autumn westward migrations across Yunnan. The northward migration reflects the temporal rhythm of gradual outbreaks from the south to the north in a year, while the return migration may explain the repeated or very severe outbreaks in the impacted areas. To form a better pest forecast and control network, attention must also be paid to the northern part of Yunnan to suppress the impact of return migration in summers and autumns.  相似文献   
382.
Identifying seasonal shifts in community assembly for multiple biological groups is important to help enhance our understanding of their ecological dynamics. However, such knowledge on lotic assemblages is still limited. In this study, we used biological traits and functional diversity indices in association with null model analyses to detect seasonal shifts in the community assembly mechanisms of lotic macroinvertebrates and diatoms in an unregulated subtropical river in China. We found that functional composition and functional diversity (FRic, FEve, FDis, MNN, and SDNN) showed seasonal variation for macroinvertebrate and diatom assemblages. Null models suggested that environmental filtering, competitive exclusion, and neutral process were all important community assembly mechanisms for both biological groups. However, environmental filtering had a stronger effect on spring macroinvertebrate assemblages than autumn assemblages, but the effect on diatom assemblages was the same in both seasons. Moreover, macroinvertebrate and diatom assemblages were shaped by different environmental factors. Macroinvertebrates were filtered mainly by substrate types, velocity, and CODMn, while diatoms were mainly shaped by altitude, substrate types, and water quality. Therefore, our study showed (a) that different biological assemblages in a river system presented similarities and differences in community assembly mechanisms, (b) that multiple processes play important roles in maintaining benthic community structure, and (c) that these patterns and underlying mechanisms are seasonally variable. Thus, we highlight the importance of exploring the community assembly mechanisms of multiple biological groups, especially in different seasons, as this is crucial to improve the understanding of river community changes and their responses to environmental degradation.  相似文献   
383.
头孢藻属(Cephaleuros)是一类寄生性藻,在分类学上位于绿藻门石莼纲橘色藻目橘色藻科。国内对头孢藻属的研究多见于它对经济作物和观赏植物的危害,而分类学研究较缺乏。为了全面系统地了解中国头孢藻属的多样性,于2012-2018年先后在多个省份采集头孢藻属标本60余份,并对其进行了形态分类学研究。结果显示,头孢藻属中国新记录种有6种,分别为:寄生头孢藻(Cephaleuros parasiticus Karsten)、德鲁特头孢藻(Cephaleuros drouetii Thompson&Wujek)、肿毛头孢藻(Cephaleuros tumidae-setae Thompson&Wujek)、散生头孢藻(Cephaleuros diffusus Thompson&Wujek)、宽阔头孢藻(Cephaleuros expansa Thompson&Wujek)、亨宁头孢藻(Cephaleuros henningsii Schmidle),对6个种的形态学特征进行了详细描述,并提供了照片资料。  相似文献   
384.
Historically, therapeutic protein production in Chinese hamster ovary (CHO) cells has been accomplished by random integration (RI) of expression plasmids into the host cell genome. More recently, the development of targeted integration (TI) host cells has allowed for recombination of plasmid DNA into a predetermined genomic locus, eliminating one contributor to clone-to-clone variability. In this study, a TI host capable of simultaneously integrating two plasmids at the same genomic site was used to assess the effect of antibody heavy chain and light chain gene dosage on antibody productivity. Our results showed that increasing antibody gene copy number can increase specific productivity, but with diminishing returns as more antibody genes are added to the same TI locus. Random integration of additional antibody DNA copies in to a targeted integration cell line showed a further increase in specific productivity, suggesting that targeting additional genomic sites for gene integration may be beneficial. Additionally, the position of antibody genes in the two plasmids was observed to have a strong effect on antibody expression level. These findings shed light on vector design to maximize production of conventional antibodies or tune expression for proper assembly of complex or bispecific antibodies in a TI system.  相似文献   
385.
Seed germination or dormancy status is strictly controlled by endogenous phytohormone and exogenous environment signals. Abscisic acid (ABA) is the important phytohormone to suppress seed germination. Ambient high temperature (HT) also suppressed seed germination, or called as secondary seed dormancy, through upregulating ABI5, the essential component of ABA signal pathway. Previous result shows that appropriate nitric oxide (NO) breaks seed dormancy through triggering S-nitrosoglutathion reductase (GSNOR1)-dependent S-nitrosylation modification of ABI5 protein, subsequently inducing the degradation of ABI5. Here we found that HT induced the degradation of GSNOR1 protein and reduced its activity, thus accumulated more reactive nitrogen species (RNS) to damage seeds viability. Furthermore, HT increased the S-nitrosylation modification of GSNOR1 protein, and triggered the degradation of GSNOR1, therefore stabilizing ABI5 to suppress seed germination. Consistently, the ABI5 protein abundance was lower in the transgenic line overexpressing GSNOR1, but higher in the gsnor mutant after HT stress. Genetic analysis showed that GSNOR1 affected seeds germination through ABI5 under HT. Taken together, our data reveals a new mechanism by which HT triggers the degradation of GSNOR1, and thus stabilizing ABI5 to suppress seed germination, such mechanism provides the possibility to enhance seed germination tolerance to HT through genetic modification of GNSOR1.  相似文献   
386.
Wang  Qianqian  Hu  Jinbo  Yang  Tianshu  Chang  Shanshan 《Protoplasma》2021,258(2):361-370
Protoplasma - As the by-products of edible oil production with rich lignin, the reserves of Camellia oleifera shell were abundant and had a great economic value. Lignin was the most important...  相似文献   
387.
Ethnopharmacological relevance: Gualou Xiebai Banxia (GLXBBX) decoction is a well-known traditional Chinese herbal formula that was first discussed in the Synopsis of the Golden Chamber by Zhang Zhongjing in the Eastern Han Dynasty. In traditional Chinese medicine, GLXBBX is commonly prescribed to treat cardiovascular diseases, such as coronary heart disease and atherosclerosis.Objective: The present study aimed to examine GLXBBX’s preventative capacity and elucidate the potential molecular mechanism of Poloxamer 407 (P407)-induced hyperlipidemia in rats.Materials and methods: Both the control and model groups received pure water, and the test group also received a GLXBBX decoction. For each administration, 3 ml of the solution was administered orally. To establish hyperlipidemia, a solution mixed with 0.25 g/kg P407 dissolved in 0.9% normal saline was injected slowly into the abdominal cavity. At the end of the study, the rats’ plasma lipid levels were calculated using an automatic biochemical analyzer to evaluate the preventative capability of the GLXBBX decoction, and the serum and liver of the rats were collected.Results: The GLXBBX decoction significantly improved P407-induced hyperlipidemia, including increased plasma triglycerides (TGs), aspartate aminotransferase (AST) elevation, and lipid accumulation. Moreover, GLXBBX decoction treatment increased lipoprotein lipase (LPL) activity and mRNA expression of LPL. Furthermore, GLXBBX significantly suppressed the mRNA expression of stearoyl-CoA desaturase (SCD1).Conclusion: GLXBBX significantly improved P407-induced hyperlipidemia, which may have been related to enhanced LPL activity, increased LPL mRNA expression, and decreased mRNA expression of SCD1.  相似文献   
388.
389.
Cui  Kai-Cheng  Liu  Min  Ke  Gui-Hua  Zhang  Xing-Yuan  Mu  Bo  Zhou  Min  Hu  Yang  Wen  Ying-Qiang 《Plant Cell, Tissue and Organ Culture》2021,146(3):621-633

As one of the most economically important fruit crops in the world, the grapevine (Vitis vinifera) suffers significant yield losses from various pathogens including powdery mildew caused by Erysiphe necator. In contrast, several wild Chinese grapevines, including Vitis pseudoreticulata accession Baihe-35-1, are highly resistant to powdery mildew pathogens. Here, we identified a grapevine gene CSN5 (COP9 signalosome complex subunit 5), designated VvCSN5, that was differentially expressed between the resistant ‘Baihe-35-1’ and susceptible ‘Thompson Seedless’ during powdery mildew isolate Erysiphe necator NAFU1 infection. Moreover, transient silencing of VvCSN5 in ‘Thompson Seedless’ leaves enhanced resistance to En NAFU1. This resistance manifested in cell wall callose deposition at attempted infection sites and hypersensitive response-like cell death of penetrated epidermal cells. Several defense-related marker genes (VvPR1, VvPR3, VvPAD4, and VvRBOHD) had higher basal expression levels in VvCSN5-silenced leaves. In addition, we found the structure and activity of CSN5 promoters in ‘Thompson Seedless’ and ‘Baihe-35-1’ were different, which may have been behind their different resistances to powdery mildew infection. Taken together, these results implied that grapevine CSN5 plays an important role in the response to powdery mildew infection.

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390.
Background: The pandemic of novel coronavirus disease 2019 (COVID-19) has become a serious public health crisis worldwide. The symptoms of COVID-19 vary from mild to severe among different age groups, but the physiological changes related to COVID-19 are barely understood.Methods: In the present study, a high-resolution mass spectrometry (HRMS)-based lipidomic strategy was used to characterize the endogenous plasma lipids for cured COVID-19 patients with different ages and symptoms. These patients were further divided into two groups: those with severe symptoms or who were elderly and relatively young patients with mild symptoms. In addition, automated lipidomic identification and alignment was conducted by LipidSearch software. Multivariate and univariate analyses were used for differential comparison.Results: Nearly 500 lipid compounds were identified in each cured COVID-19 group through LipidSearch software. At the level of lipid subclasses, patients with severe symptoms or elderly patients displayed dramatic changes in plasma lipidomic alterations, such as increased triglycerides and decreased cholesteryl esters (ChE). Some of these differential lipids might also have essential biological functions. Furthermore, the differential analysis of plasma lipids among groups was performed to provide potential prognostic indicators, and the change in signaling pathways.Conclusions: Dyslipidemia was observed in cured COVID-19 patients due to the viral infection and medical treatment, and the discharged patients should continue to undergo consolidation therapy. This work provides valuable knowledge about plasma lipid markers and potential therapeutic targets of COVID-19 and essential resources for further research on the pathogenesis of COVID-19.  相似文献   
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