Occurrence of neurofibrillary tangles of the tau protein is a hallmark of tau-related neurodegenerative diseases, i.e. Alzheimer's disease(AD) and frontotemporal dementia. The pathological mechanism underlying AD ...Occurrence of neurofibrillary tangles of the tau protein is a hallmark of tau-related neurodegenerative diseases, i.e. Alzheimer's disease(AD) and frontotemporal dementia. The pathological mechanism underlying AD remains poorly understood, and effective treatments are still unavailable to mitigate the disease.Inhibiting of tau aggregation and disrupting the existing fibrils are key targets in drug discovery towards preventing or curing AD. In this study, grape seed proanthocyanidins(GSPs) was found to effectively inhibit the repeat domain of tau(tau-RD) aggregation and disaggregate tau-RD fibrils in a concentrationdependent manner by inhibiting β-sheet formation of tau-RD. In cells, GSPs relieved cytotoxicity induced by tau-RD aggregates. Molecular dynamics simulations indicated that strong hydrogen bonding,hydrophobic interaction and π-π stacking between GSPs and tau-RD protein were major reasons why GSPs had high inhibitory activity on tau-RD fibrillogenesis. These results provide preliminary data to develop GSPs into medicines, foodstuffs or nutritional supplements for AD patients, suggesting that GSPs could be a candidate molecule in the drug design for AD therapeutics.展开更多
Yellow seed trait is a desirable characteristic with potential for increasing seed quality and commercial value in rapeseed,and anthocyanin and proanthocyanidins(PAs)are major seed-coat pigments.Few transcription fact...Yellow seed trait is a desirable characteristic with potential for increasing seed quality and commercial value in rapeseed,and anthocyanin and proanthocyanidins(PAs)are major seed-coat pigments.Few transcription factors involved in the regulation of anthocyanin and PAs biosynthesis have been characterized in rapeseed.In this study,we identified a transcription factor gene BnbHLH92a(BnaA06T0441000ZS)in rapeseed.Overexpressing BnbHLH92a both in Arabidopsis and in rapeseed reduced levels of anthocyanin and PAs.Correspondingly,the expression profiles of anthocyanin and PA biosynthesis genes(TT3,BAN,TT8,TT18,and TTG1)were shown by quantitative real-time PCR to be inhibited in BnbHLH92a-overexpressing Arabidopsis seeds,indicating that BnbHLH92a represses the anthocyanin and PA biosynthesis pathway in Arabidopsis.BnbHLH92a physically interacts with the BnTTG1 protein and represses the biosynthesis of anthocyanins and PAs in rapeseed.BnbHLH92a also binds directly to the BnTT18 promoter and represses its expression.These results suggest that BnbHLH92a is a novel upstream regulator of flavonoid biosynthesis in B.napus.展开更多
利用植物多酚原花青素(oligomeric proanthocyanidins,OPC)与大豆分离蛋白(soybean protein isolate,SPI)的相互作用,采用葡萄糖酸内酯诱导结合超声波处理制备OPC-SPI凝胶,旨在改善SPI凝胶性能。研究不同浓度OPC(0.1%、0.3%、0.5%)对SP...利用植物多酚原花青素(oligomeric proanthocyanidins,OPC)与大豆分离蛋白(soybean protein isolate,SPI)的相互作用,采用葡萄糖酸内酯诱导结合超声波处理制备OPC-SPI凝胶,旨在改善SPI凝胶性能。研究不同浓度OPC(0.1%、0.3%、0.5%)对SPI凝胶流变特性和抗氧化活性的影响。结果表明,随着OPC浓度的增加,包埋率增加,荷载量减小,最大荷载量达到35.5753μg/mg。随着OPC浓度的增加,OPC-SPI凝胶的弹性模量和黏性模量增加,损耗因子随之降低,对频率的依赖性降低;但对凝胶的黏度无显著差异。OPC-SPI对1,1-二苯基-2-三硝基苯肼(DPPH)自由基、2,2′-联氮双(3-乙基苯并噻唑啉-6-磺酸)二铵盐(ABTS)自由基以及羟自由基的清除能力优于SPI。OPC能够有效增强SPI的凝胶黏弹性和抗氧化活性,为进一步开发新型抗氧化复合SPI凝胶提供了理论依据。展开更多
The yellow seed trait is preferred by breeders for its potential to improve the seed quality and commercial value of Brassica napus.In the present study,we produced yellow seed mutants using a CRISPR/Cas9 system when ...The yellow seed trait is preferred by breeders for its potential to improve the seed quality and commercial value of Brassica napus.In the present study,we produced yellow seed mutants using a CRISPR/Cas9 system when the two BnPAP2 homologs were knocked out.Histochemical staining of the seed coat demonstrated that proanthocyanidin accumulation was significantly reduced in the pap2 double mutants and decreased specifically in the endothelial and palisade layer cells of the seed coat.Transcriptomic and metabolite profiling analysis suggested that disruption of the BnPAP2 genes could reduce the expression of structural and regulated genes in the phenylpropanoid and flavonoid biosynthetic pathways.The broad suppression of these genes might hinder proanthocyanidin accumulation during seed development,and thereby causing the yellow seed trait in B.napus.These results indicate that BnPAP2 might play a vital role in the regulatory network controlling proanthocyanidin accumulation.展开更多
基金supported by the National Natural Science Foundation of China (21878262)。
文摘Occurrence of neurofibrillary tangles of the tau protein is a hallmark of tau-related neurodegenerative diseases, i.e. Alzheimer's disease(AD) and frontotemporal dementia. The pathological mechanism underlying AD remains poorly understood, and effective treatments are still unavailable to mitigate the disease.Inhibiting of tau aggregation and disrupting the existing fibrils are key targets in drug discovery towards preventing or curing AD. In this study, grape seed proanthocyanidins(GSPs) was found to effectively inhibit the repeat domain of tau(tau-RD) aggregation and disaggregate tau-RD fibrils in a concentrationdependent manner by inhibiting β-sheet formation of tau-RD. In cells, GSPs relieved cytotoxicity induced by tau-RD aggregates. Molecular dynamics simulations indicated that strong hydrogen bonding,hydrophobic interaction and π-π stacking between GSPs and tau-RD protein were major reasons why GSPs had high inhibitory activity on tau-RD fibrillogenesis. These results provide preliminary data to develop GSPs into medicines, foodstuffs or nutritional supplements for AD patients, suggesting that GSPs could be a candidate molecule in the drug design for AD therapeutics.
基金supported by the National Natural Science Foundation of China(32072093,31830067)the China Agriculture Research System of MOF and MARA,the Science and Enterprise Consortium Project of Chongqing(cqnyncw-kqlhtxm)+1 种基金the Innovation and Entrepreneurship Training Program for Undergraduates(S202010635197)the 111 Project(B12006).
文摘Yellow seed trait is a desirable characteristic with potential for increasing seed quality and commercial value in rapeseed,and anthocyanin and proanthocyanidins(PAs)are major seed-coat pigments.Few transcription factors involved in the regulation of anthocyanin and PAs biosynthesis have been characterized in rapeseed.In this study,we identified a transcription factor gene BnbHLH92a(BnaA06T0441000ZS)in rapeseed.Overexpressing BnbHLH92a both in Arabidopsis and in rapeseed reduced levels of anthocyanin and PAs.Correspondingly,the expression profiles of anthocyanin and PA biosynthesis genes(TT3,BAN,TT8,TT18,and TTG1)were shown by quantitative real-time PCR to be inhibited in BnbHLH92a-overexpressing Arabidopsis seeds,indicating that BnbHLH92a represses the anthocyanin and PA biosynthesis pathway in Arabidopsis.BnbHLH92a physically interacts with the BnTTG1 protein and represses the biosynthesis of anthocyanins and PAs in rapeseed.BnbHLH92a also binds directly to the BnTT18 promoter and represses its expression.These results suggest that BnbHLH92a is a novel upstream regulator of flavonoid biosynthesis in B.napus.
文摘利用植物多酚原花青素(oligomeric proanthocyanidins,OPC)与大豆分离蛋白(soybean protein isolate,SPI)的相互作用,采用葡萄糖酸内酯诱导结合超声波处理制备OPC-SPI凝胶,旨在改善SPI凝胶性能。研究不同浓度OPC(0.1%、0.3%、0.5%)对SPI凝胶流变特性和抗氧化活性的影响。结果表明,随着OPC浓度的增加,包埋率增加,荷载量减小,最大荷载量达到35.5753μg/mg。随着OPC浓度的增加,OPC-SPI凝胶的弹性模量和黏性模量增加,损耗因子随之降低,对频率的依赖性降低;但对凝胶的黏度无显著差异。OPC-SPI对1,1-二苯基-2-三硝基苯肼(DPPH)自由基、2,2′-联氮双(3-乙基苯并噻唑啉-6-磺酸)二铵盐(ABTS)自由基以及羟自由基的清除能力优于SPI。OPC能够有效增强SPI的凝胶黏弹性和抗氧化活性,为进一步开发新型抗氧化复合SPI凝胶提供了理论依据。
基金supported by the National Natural Science Foundation of China(31971980,U19A2029)The science and technology innovation Program of Hunan Province,China(2023RC1077)+1 种基金the Agricultural Science and Technology Innovation Foundation of Hunan,China(2022CX55)the Scientific Research Fund of Hunan Provincial Science and Technology Department,China(2021JC0007)。
文摘The yellow seed trait is preferred by breeders for its potential to improve the seed quality and commercial value of Brassica napus.In the present study,we produced yellow seed mutants using a CRISPR/Cas9 system when the two BnPAP2 homologs were knocked out.Histochemical staining of the seed coat demonstrated that proanthocyanidin accumulation was significantly reduced in the pap2 double mutants and decreased specifically in the endothelial and palisade layer cells of the seed coat.Transcriptomic and metabolite profiling analysis suggested that disruption of the BnPAP2 genes could reduce the expression of structural and regulated genes in the phenylpropanoid and flavonoid biosynthetic pathways.The broad suppression of these genes might hinder proanthocyanidin accumulation during seed development,and thereby causing the yellow seed trait in B.napus.These results indicate that BnPAP2 might play a vital role in the regulatory network controlling proanthocyanidin accumulation.
