Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease resistance.Despite this,only a...Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease resistance.Despite this,only a few lesion mimic genes have been identified in wheat.In this investigation,a lesion mimic wheat mutant named je0297 was discovered,showing no alteration in yield components when compared to the wild type(WT).Segregation ratio analysis of the F_(2)individuals resulting from the cross between the WT and the mutant revealed that the lesion mimic was governed by a single recessive gene in je0297.Using Bulked segregant analysis(BSA)and exome capture sequencing,we mapped the lesion mimic gene designated as lm6 to chromosome 6BL.Further gene fine mapping using 3315 F_(2)individuals delimited the lm6 within a 1.18 Mb region.Within this region,we identified 16 high-confidence genes,with only two displaying mutations in je0297.Notably,one of the two genes,responsible for encoding flavonol synthase,exhibited altered expression levels.Subsequent phenotype analysis of TILLING mutants confirmed that the gene encoding flavonol synthase was indeed the causal gene for lm6.Transcriptome sequencing analysis revealed that the DEGs between the WT and mutant were significantly enriched in KEGG pathways related to flavonoid biosynthesis,including flavone and flavonol biosynthesis,isoflavonoid biosynthesis,and flavonoid biosynthesis pathways.Furthermore,more than 30 pathogen infection-related(PR)genes exhibited upregulation in the mutant.Corresponding to this expression pattern,the flavonoid content in je0297 showed a significant decrease in the 4^(th)leaf,accompanied by a notable accumulation of reactive oxygen,which likely contributed to the development of lesion mimic in the mutant.This investigation enhances our comprehension of cell death signaling pathways and provides a valuable gene resource for the breeding of disease-resistant wheat.展开更多
A new flavonol glycoside, named neosmitilbin was isolated form the rhizome of Smilax glabra. Its structure and absolute configuration were elucidated on the basis of spectroscopic studies.
目的:建立参葛补肾胶囊中淫羊藿苷、朝藿定A、朝藿定B、朝藿定C含量的HPLC测定方法。方法:采用高效液相色谱法,色谱柱为Waters ACQUITY UPLC HSS T3 C 18(2.1×100 mm,1.8μm),流动相为乙腈-0.05%磷酸水溶液体系,梯度洗脱,流速为0.3...目的:建立参葛补肾胶囊中淫羊藿苷、朝藿定A、朝藿定B、朝藿定C含量的HPLC测定方法。方法:采用高效液相色谱法,色谱柱为Waters ACQUITY UPLC HSS T3 C 18(2.1×100 mm,1.8μm),流动相为乙腈-0.05%磷酸水溶液体系,梯度洗脱,流速为0.3 mL·min^(-1),检测波长为320 nm,柱温为30℃,进样量为2μL。以淫羊藿苷为内参物,采用斜率校正法计算其他3个成分的相对校正因子,比较外标法和一测多评法(QAMS)测定结果,验证一测多评法的可行性及准确性。结果:淫羊藿苷、朝藿定A、朝藿定B、朝藿定C分别在7.130~713.38μg·mL^(-1)、1.284~128.4μg·mL^(-1)、5.108~510.8μg·mL^(-1)、4.360~435.67μg·mL^(-1)质量浓度范围内存在良好的线性关系,线性系数R 2均大于0.99,平均加样回收率分别为104.5%、99.69%、100%、98.59%,RSD分别为1.4%、2.7%、1.2%、2.8%。朝藿定A、朝藿定B、朝藿定C的相对校正因子为1.31、1.19、1.17。一测多评法和外标法测定结果比较,其差异无统计学意义(P>0.05)。结论:该方法准确、简便、重复性好,可作为参葛补肾胶囊中淫羊藿总黄酮醇苷的质量控制研究。展开更多
A new isoprenylated flavonol, named broussonol A (1) was isolated from the leaves of Broussonetia kazinoki Sieb. The structure of broussonol A was characterized by chemical and spectral methods.
A new flavonol glycoside, isorhamnetin-3-O-b-D-xyloside, was isolated from the extract of leaves and twigs of Alchornea davidii (Euphorbiaceae). Its structure was established on the basis of the spectral analysis and ...A new flavonol glycoside, isorhamnetin-3-O-b-D-xyloside, was isolated from the extract of leaves and twigs of Alchornea davidii (Euphorbiaceae). Its structure was established on the basis of the spectral analysis and chemical degradation. Antimicrobial assay showed that it moderately inhibited the growth of test bacteria (Staphylococcus aureus, Bacillus subtilis and Pseudomonas fluorescens) and fungi (Candida albicans, Aspergillus niger and Trichophyton rubrum) with MICs at 50 g/mL.展开更多
Three new flavonol glycosides were isolated from the leaves of Helicia nilagirica Beed.. The structures were elucidated as kaempferol-3-O-b-D-xylopyranosyl-(16)-b-D-glyco- pyranosyl-(12)-a-L-rhamnopyranoside, querce...Three new flavonol glycosides were isolated from the leaves of Helicia nilagirica Beed.. The structures were elucidated as kaempferol-3-O-b-D-xylopyranosyl-(16)-b-D-glyco- pyranosyl-(12)-a-L-rhamnopyranoside, quercetin-3-O-b-D-xylopyranosyl-(16)-b-D-glycopy- ranosyl-(12)-[-b-D-xylopyranosyl-(14)]-a-L-rhamnopyranoside, and quercetin-3-O-b-D- xylopyranosyl-(16)-b-D-glycopyranosyl-(12)-a-L-rhamnopyranoside, named as Helicianeoside A、B and C, respectively.展开更多
The cell cycle checkpoint system play a pivotal role in the cellular DNA damage response, and the discovery of checkpoint inhibitors is expected to sensitize current cancer therapies. Checkpoint signaling cascades are...The cell cycle checkpoint system play a pivotal role in the cellular DNA damage response, and the discovery of checkpoint inhibitors is expected to sensitize current cancer therapies. Checkpoint signaling cascades are critically modulated by ATM (ataxia telangiectasia-mutated) and its related molecules. Generally, ATM primarily responds to ionizing irradiation-induced DNA double-strand breaks. Heavy ions from an accelerated carbon ion beam have been used to cure cancer because they are more effective than ionizing irradiation such as X-ray and γ-radiation in terms of biological damage. In a previous study, we demonstrated that a persimmon leaf flavonol (PLF) promoted the cytotoxic effect of chemotherapeutic agents on cancer cells through inhibition of checkpoint activities, especially in the ATM dependent pathway. The present study investigated whether PLF inhibits checkpoint activity during the DNA damage response induced by heavy ion irradiation. Treatment with PLF significantly increased the cytotoxicity of heavy ion irradiation in A549 adenocarcinoma cells. The phosphorylation of checkpoint proteins such as p53, SMC1, and Chk1 was increased by heavy ions. PLF reduced the phosphorylation of checkpoint proteins. Pre-treatment with PLF significantly prevented the decrease of mitotic cells in heavy ion-exposed cells. We further evaluated tumor volume in SCID mice inoculated with human lung adenocarcinoma A549 cells. The combination treatment of PLF and heavy ion resulted in a decrease of tumor volume compared with controls, although PLF itself did not exhibit any effect. These results indicate that PLF inhibits tumor growth through modulation of the DNA damage response. PLF may be useful for clinical application in combination with heavy ion radiotherapy.展开更多
Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside (1) and tamarixetin 3-O-α-L-ribopyranoside (2) were isolated from the leaves of Bridelia tomentosa. Their structures wer...Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside (1) and tamarixetin 3-O-α-L-ribopyranoside (2) were isolated from the leaves of Bridelia tomentosa. Their structures were elucidated by 1D and 2D NMR analysis, as well as MS and IR spectra.展开更多
Two new diacetylated flavonol glycosides, kampferol-3-O--3? 6?diacetylglucopyrano- side and quercetin-3-O--3? 6?diacetylglucopyranoside were isolated from knoxia corymbosa. Their structures were elucidated by spectro...Two new diacetylated flavonol glycosides, kampferol-3-O--3? 6?diacetylglucopyrano- side and quercetin-3-O--3? 6?diacetylglucopyranoside were isolated from knoxia corymbosa. Their structures were elucidated by spectroscopic evidents.展开更多
A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, I...A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, IR, MS, NMR and 1H-1H COSY) and confirmed by total synthesis.展开更多
A new benzofuranolignan austrafuran A (1) and a new flavonol derivative 5,7,2′,4′-tetrahydroxy-3-methoxyflavone (2) were isolated from the stem of Morus australis. Their structures were determined on the basis o...A new benzofuranolignan austrafuran A (1) and a new flavonol derivative 5,7,2′,4′-tetrahydroxy-3-methoxyflavone (2) were isolated from the stem of Morus australis. Their structures were determined on the basis of spectroscopic evidences.展开更多
A new flavonol oligosaccharide, quercetin-3-O-[b-D-xylopyranosyl-(12)- a-L-rhamnopyranosyl-(16)]-b-D-glucopyranoside-3-O-b-D-glucopyranoside, named aescuflavoside was isolated from Aesculus chinensis. Its structure w...A new flavonol oligosaccharide, quercetin-3-O-[b-D-xylopyranosyl-(12)- a-L-rhamnopyranosyl-(16)]-b-D-glucopyranoside-3-O-b-D-glucopyranoside, named aescuflavoside was isolated from Aesculus chinensis. Its structure was elucidated by spectra FAB-MS, 1D NMR and 2D NMR including 1H NMR, 13C NMR, HMQC and HMBC techniques.展开更多
基金supported by the National Key Research and Development Program of China(2022YFD1200700)the Nuclear Energy Development Research Program of the State Administration of Science,Technology,and Industry for National Defense(Crop Varietal Improvement and Insect Pests Control by Nuclear Radiation)the China Agriculture Research System of MOF and MARA(CARS-03)。
文摘Lesion mimic often exhibits leaf disease-like symptoms even in the absence of pathogen infection,and is characterized by a hypersensitive-response(HR)that closely linked to plant disease resistance.Despite this,only a few lesion mimic genes have been identified in wheat.In this investigation,a lesion mimic wheat mutant named je0297 was discovered,showing no alteration in yield components when compared to the wild type(WT).Segregation ratio analysis of the F_(2)individuals resulting from the cross between the WT and the mutant revealed that the lesion mimic was governed by a single recessive gene in je0297.Using Bulked segregant analysis(BSA)and exome capture sequencing,we mapped the lesion mimic gene designated as lm6 to chromosome 6BL.Further gene fine mapping using 3315 F_(2)individuals delimited the lm6 within a 1.18 Mb region.Within this region,we identified 16 high-confidence genes,with only two displaying mutations in je0297.Notably,one of the two genes,responsible for encoding flavonol synthase,exhibited altered expression levels.Subsequent phenotype analysis of TILLING mutants confirmed that the gene encoding flavonol synthase was indeed the causal gene for lm6.Transcriptome sequencing analysis revealed that the DEGs between the WT and mutant were significantly enriched in KEGG pathways related to flavonoid biosynthesis,including flavone and flavonol biosynthesis,isoflavonoid biosynthesis,and flavonoid biosynthesis pathways.Furthermore,more than 30 pathogen infection-related(PR)genes exhibited upregulation in the mutant.Corresponding to this expression pattern,the flavonoid content in je0297 showed a significant decrease in the 4^(th)leaf,accompanied by a notable accumulation of reactive oxygen,which likely contributed to the development of lesion mimic in the mutant.This investigation enhances our comprehension of cell death signaling pathways and provides a valuable gene resource for the breeding of disease-resistant wheat.
文摘A new flavonol glycoside, named neosmitilbin was isolated form the rhizome of Smilax glabra. Its structure and absolute configuration were elucidated on the basis of spectroscopic studies.
文摘A new isoprenylated flavonol, named broussonol A (1) was isolated from the leaves of Broussonetia kazinoki Sieb. The structure of broussonol A was characterized by chemical and spectral methods.
基金supported by the National Natural Science Foundation (No. 39970083).
文摘A new flavonol glycoside, isorhamnetin-3-O-b-D-xyloside, was isolated from the extract of leaves and twigs of Alchornea davidii (Euphorbiaceae). Its structure was established on the basis of the spectral analysis and chemical degradation. Antimicrobial assay showed that it moderately inhibited the growth of test bacteria (Staphylococcus aureus, Bacillus subtilis and Pseudomonas fluorescens) and fungi (Candida albicans, Aspergillus niger and Trichophyton rubrum) with MICs at 50 g/mL.
文摘Three new flavonol glycosides were isolated from the leaves of Helicia nilagirica Beed.. The structures were elucidated as kaempferol-3-O-b-D-xylopyranosyl-(16)-b-D-glyco- pyranosyl-(12)-a-L-rhamnopyranoside, quercetin-3-O-b-D-xylopyranosyl-(16)-b-D-glycopy- ranosyl-(12)-[-b-D-xylopyranosyl-(14)]-a-L-rhamnopyranoside, and quercetin-3-O-b-D- xylopyranosyl-(16)-b-D-glycopyranosyl-(12)-a-L-rhamnopyranoside, named as Helicianeoside A、B and C, respectively.
文摘The cell cycle checkpoint system play a pivotal role in the cellular DNA damage response, and the discovery of checkpoint inhibitors is expected to sensitize current cancer therapies. Checkpoint signaling cascades are critically modulated by ATM (ataxia telangiectasia-mutated) and its related molecules. Generally, ATM primarily responds to ionizing irradiation-induced DNA double-strand breaks. Heavy ions from an accelerated carbon ion beam have been used to cure cancer because they are more effective than ionizing irradiation such as X-ray and γ-radiation in terms of biological damage. In a previous study, we demonstrated that a persimmon leaf flavonol (PLF) promoted the cytotoxic effect of chemotherapeutic agents on cancer cells through inhibition of checkpoint activities, especially in the ATM dependent pathway. The present study investigated whether PLF inhibits checkpoint activity during the DNA damage response induced by heavy ion irradiation. Treatment with PLF significantly increased the cytotoxicity of heavy ion irradiation in A549 adenocarcinoma cells. The phosphorylation of checkpoint proteins such as p53, SMC1, and Chk1 was increased by heavy ions. PLF reduced the phosphorylation of checkpoint proteins. Pre-treatment with PLF significantly prevented the decrease of mitotic cells in heavy ion-exposed cells. We further evaluated tumor volume in SCID mice inoculated with human lung adenocarcinoma A549 cells. The combination treatment of PLF and heavy ion resulted in a decrease of tumor volume compared with controls, although PLF itself did not exhibit any effect. These results indicate that PLF inhibits tumor growth through modulation of the DNA damage response. PLF may be useful for clinical application in combination with heavy ion radiotherapy.
文摘Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside (1) and tamarixetin 3-O-α-L-ribopyranoside (2) were isolated from the leaves of Bridelia tomentosa. Their structures were elucidated by 1D and 2D NMR analysis, as well as MS and IR spectra.
文摘Two new diacetylated flavonol glycosides, kampferol-3-O--3? 6?diacetylglucopyrano- side and quercetin-3-O--3? 6?diacetylglucopyranoside were isolated from knoxia corymbosa. Their structures were elucidated by spectroscopic evidents.
文摘A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, IR, MS, NMR and 1H-1H COSY) and confirmed by total synthesis.
基金the National Natural Science Foundation of China(No.2042030 and 20572133)for financial support.
文摘A new benzofuranolignan austrafuran A (1) and a new flavonol derivative 5,7,2′,4′-tetrahydroxy-3-methoxyflavone (2) were isolated from the stem of Morus australis. Their structures were determined on the basis of spectroscopic evidences.
文摘A new flavonol oligosaccharide, quercetin-3-O-[b-D-xylopyranosyl-(12)- a-L-rhamnopyranosyl-(16)]-b-D-glucopyranoside-3-O-b-D-glucopyranoside, named aescuflavoside was isolated from Aesculus chinensis. Its structure was elucidated by spectra FAB-MS, 1D NMR and 2D NMR including 1H NMR, 13C NMR, HMQC and HMBC techniques.