Background and Purpose: Thrombotic disease is a leading cause of death in industrialized countries. The development of atherosclerosis is a major underlying pathogenesis. Atherosclerotic lesions are largely related to...Background and Purpose: Thrombotic disease is a leading cause of death in industrialized countries. The development of atherosclerosis is a major underlying pathogenesis. Atherosclerotic lesions are largely related to abnormalities in lipid metabolism, and improvement of dietary habits is of great significance. Chlorella is a unicellular organism belonging to the green algae family, and is consumed worldwide as a functional food for the purpose of health promotion due to its excellent nutritional balance including high quality protein. In this study, we investigated the effects of long-term consumption of Chlorella as a food on the development of atherosclerosis and its ability to dissolve thrombi caused by the disruption of the atherosclerotic layer as a functional study of Chlorella. Methods: ApoE<sup>−/−</sup> and Ldlr<sup>−/−</sup> double-knockout mice were fed a chlorella-supplemented experimental diet for 14 weeks. The Entire aorta method was used to measure atherosclerosis development, and the area of sclerotic vessels was evaluated as a percentage of the total area of vessels. In addition, mRNA levels of lipid metabolism-related proteins in the liver and blood vessels were analyzed, as well as blood lipoprotein analysis. Spontaneous thrombolytic activity was measured by measuring the change in volume over time of thrombus formed in microvessel running over the cremaster muscle of the mice using the He-Ne laser-induced thrombus model. Results: There was no significant difference between the two groups in atherosclerosis development compared to the placebo group. However, a significant decrease in SREBP-1 mRNA level and a significant increase in mRNA levels of LXR and CPY71a were observed in the chlorella group. Cholesterol and TG levels in each lipoprotein fraction did not differ between the two groups. On the other hand, thrombolysis in vivo was not significantly different between the two groups in terms of thrombus volume at 60 minutes after thrombus formation. However, a trend toward decreased PAI-1 and TAFI mRNA expression levels was observed in the chlorella group. Conclusion: Intake of chlorella as a food suggested an effect on cholesterol catabolism, increased bile acid synthesis, improved lipid metabolism, and inhibited the development of atherosclerosis. Furthermore, it was suggested that chlorella may suppress the expression of fibrinolytic inhibitory factor and enhance thrombolytic activity.展开更多
Artemisia annua is an important preferred host of the mirid bug Apolygus lucorum in autumn.Volatiles emitted from A.annua attract A.Iucorum.Volatile artemisinic acid of A.annua is a precursor of artemisinin that has b...Artemisia annua is an important preferred host of the mirid bug Apolygus lucorum in autumn.Volatiles emitted from A.annua attract A.Iucorum.Volatile artemisinic acid of A.annua is a precursor of artemisinin that has been widely investigated in the Chinese herbal medicine field.However,little is known at this point about the biological roles of artemisinic acid in regulating the behavioral trends of A.lucorum.In this study,we collected volatiles from A.annua at the seedling stage by using headspace solid phase microextraction(HS-SPME).Gas chromatography-mass spectrometry(GC-MS) analysis showed that approximately 11.03±6.00 and 238.25±121.67 ng hartemisinic acid were detected in volatile samples and milled samples,respectively.Subsequently,a key gene for artemisinic acid synthesis,the cytochrome P450 gene cyp71 av1,was expressed in engineered Saccharomyces cerevisiae to catalyze the production of artemisinic acid.After the addition of exogenous artemisinic alcohol or artemisinic aldehyde,artemisinic acid was identified as the product of the expressed gene.In electroantennogram(EAG) recordings,3-day-old adult A.lucorum showed significant electrophysiological responses to artemisinic alcohol,artemisinic aldehyde and artemisinic acid.Furthermore,3-day-old female bugs were significantly attracted by artemisinic acid and artemisinic alcohol at a concentration of 10 mmol L,whereas 3-day-old male bugs were attracted significantly by 10 mmol Lartemisinic acid and artemisinic aldehyde.We propose that artemisinic acid and its precursors could be used as potential attractant components for the design of novel integrated pest management strategies to control A.lucorum.展开更多
Plants of Artemisia annua produce artemisinin, a sesquiterpene lactone widely used in malaria treatment. Amorpha-4,11-diene synthase （ADS）, a sesquiterpene synthase, and CYP71AV1, a P450 monooxygenase, are two key e...Plants of Artemisia annua produce artemisinin, a sesquiterpene lactone widely used in malaria treatment. Amorpha-4,11-diene synthase （ADS）, a sesquiterpene synthase, and CYP71AV1, a P450 monooxygenase, are two key enzymes of the artemisinin biosynthesis pathway. Accumulation of artemisinin can be induced by the phytohormone jasmonate （JA）. Here, we report the characterization of two JA-responsive AP2 family transcription factors-AaERF1 and AaERF2-from A. annua L. Both genes were highly expressed in inflorescences and strongly induced by JA. Yeast one- hybrid and electrophoretic mobility shift assay （EMSA） showed that they were able to bind to the CRTDREHVCBF2 （CBF2） and RAVlAAT （RAA） motifs present in both ADS and CYP71AV1 promoters. Transient expression of either AaERF1 or AaERF2 in tobacco induced the promoter activities of ADS or CYP71AV1, and the transgenic A. annua plants overexpressing either transcription factor showed elevated transcript levels of both ADS and CYP71AV1, resulting in increased accumulation of artemisinin and artemisinic acid. By contrast, the contents of these two metabolites were reduced in the RNAi transgenic lines in which expression of AaERF1 or AaERF2 was suppressed. These results demonstrate that AaERF1 and AaERF2 are two positive regulators of artemisinin biosynthesis and are of great value in genetic engineering of arte- misinin production.展开更多
Apart from their primordial role in protein synthesis,t RNAs can be cleaved to produce t RNA-derived small RNAs(ts RNAs).The biological functions of ts RNAs in plants remain largely unknown.In this study,we developed ...Apart from their primordial role in protein synthesis,t RNAs can be cleaved to produce t RNA-derived small RNAs(ts RNAs).The biological functions of ts RNAs in plants remain largely unknown.In this study,we developed Rtc B ligation-based small RNA(s RNA)sequencing,a method that captures and distinguishes between 3′-2′,3′-cyclic-phosphate(c P)/phosphate(P)-terminated s RNAs and 3′-OH-terminated s RNAs,and profiled 5′ts RNAs and 5′t RNA halves in Arabidopsis thaliana.We found that Arabidopsis 5′ts RNAs and 5′t RNA halves predominantly contain a c P at the 3′end and require S-like RNase 1(RNS1)and RNS3 for their production.One of the most abundant 5′ts RNAs,5′ts R-Ala,by associating with AGO1,negatively regulates Cytochrome P45071 A13(CYP71 A13)expression and camalexin biosynthesis to repress anti-fungal defense.Interestingly,5′ts R-Ala is downregulated upon fungal infection.Our study provides a global view of 5′ts RNAs and 5′t RNA halves in Arabidopsis and unravels an important role of a 5′ts RNA in regulating anti-fungal defense.展开更多
An expressed sequence tag(EST)obtained from a subtractive-suppression hybridization cDNA library constructed using Catharanthus roseus cell line C_(20)hi and its parental cell line C_(20)D was used to clone a ful-leng...An expressed sequence tag(EST)obtained from a subtractive-suppression hybridization cDNA library constructed using Catharanthus roseus cell line C_(20)hi and its parental cell line C_(20)D was used to clone a ful-length cytochrome P450 cDNA of cyp71d1.The encoded polypeptide contained 507 amino acids with 39-56% identity to other CYP7ID subfamily members at the.amino acid level.Expression characteristics of cyp71d1 were determined using semi-quantitative RT-PCR.The cyp71d1 transcript was expressed in all three cell lines with the highest level in the cell line C_(20)hi.In the mature C.roseus plant,the cyp71d1 cDNA was highly expressed in petals,roots and stems,but very weakly expressed in young leaves.Its transcription level increased with the development of flowers.2,4-D could down-regulate the transcription of cyp71d1,as did KT,but only to a minor degree.Neither light nor yeast elicitor could induce the transcription of cyp71d1.展开更多
文摘Background and Purpose: Thrombotic disease is a leading cause of death in industrialized countries. The development of atherosclerosis is a major underlying pathogenesis. Atherosclerotic lesions are largely related to abnormalities in lipid metabolism, and improvement of dietary habits is of great significance. Chlorella is a unicellular organism belonging to the green algae family, and is consumed worldwide as a functional food for the purpose of health promotion due to its excellent nutritional balance including high quality protein. In this study, we investigated the effects of long-term consumption of Chlorella as a food on the development of atherosclerosis and its ability to dissolve thrombi caused by the disruption of the atherosclerotic layer as a functional study of Chlorella. Methods: ApoE<sup>−/−</sup> and Ldlr<sup>−/−</sup> double-knockout mice were fed a chlorella-supplemented experimental diet for 14 weeks. The Entire aorta method was used to measure atherosclerosis development, and the area of sclerotic vessels was evaluated as a percentage of the total area of vessels. In addition, mRNA levels of lipid metabolism-related proteins in the liver and blood vessels were analyzed, as well as blood lipoprotein analysis. Spontaneous thrombolytic activity was measured by measuring the change in volume over time of thrombus formed in microvessel running over the cremaster muscle of the mice using the He-Ne laser-induced thrombus model. Results: There was no significant difference between the two groups in atherosclerosis development compared to the placebo group. However, a significant decrease in SREBP-1 mRNA level and a significant increase in mRNA levels of LXR and CPY71a were observed in the chlorella group. Cholesterol and TG levels in each lipoprotein fraction did not differ between the two groups. On the other hand, thrombolysis in vivo was not significantly different between the two groups in terms of thrombus volume at 60 minutes after thrombus formation. However, a trend toward decreased PAI-1 and TAFI mRNA expression levels was observed in the chlorella group. Conclusion: Intake of chlorella as a food suggested an effect on cholesterol catabolism, increased bile acid synthesis, improved lipid metabolism, and inhibited the development of atherosclerosis. Furthermore, it was suggested that chlorella may suppress the expression of fibrinolytic inhibitory factor and enhance thrombolytic activity.
基金supported by the National Natural Science Foundation of China (31772176 and 31972338)the National Key Research and Development Program of China (2019YFD0300100)
文摘Artemisia annua is an important preferred host of the mirid bug Apolygus lucorum in autumn.Volatiles emitted from A.annua attract A.Iucorum.Volatile artemisinic acid of A.annua is a precursor of artemisinin that has been widely investigated in the Chinese herbal medicine field.However,little is known at this point about the biological roles of artemisinic acid in regulating the behavioral trends of A.lucorum.In this study,we collected volatiles from A.annua at the seedling stage by using headspace solid phase microextraction(HS-SPME).Gas chromatography-mass spectrometry(GC-MS) analysis showed that approximately 11.03±6.00 and 238.25±121.67 ng hartemisinic acid were detected in volatile samples and milled samples,respectively.Subsequently,a key gene for artemisinic acid synthesis,the cytochrome P450 gene cyp71 av1,was expressed in engineered Saccharomyces cerevisiae to catalyze the production of artemisinic acid.After the addition of exogenous artemisinic alcohol or artemisinic aldehyde,artemisinic acid was identified as the product of the expressed gene.In electroantennogram(EAG) recordings,3-day-old adult A.lucorum showed significant electrophysiological responses to artemisinic alcohol,artemisinic aldehyde and artemisinic acid.Furthermore,3-day-old female bugs were significantly attracted by artemisinic acid and artemisinic alcohol at a concentration of 10 mmol L,whereas 3-day-old male bugs were attracted significantly by 10 mmol Lartemisinic acid and artemisinic aldehyde.We propose that artemisinic acid and its precursors could be used as potential attractant components for the design of novel integrated pest management strategies to control A.lucorum.
基金This research was supported by State Key Basic Research Program of China （2007CB108800）, the National Natural Science Foundation of China （30630008）, and the National HighTech Program of China （2007AA021501 ）.ACKNO WLEDGMENTS We thank CYP71AV1. discussions Ke-Xuan Tang for supplying the promoter sequence of We thank Ji-Rong Huang and Gao-Jie Hong for he pfu No conflict of interest declared
文摘Plants of Artemisia annua produce artemisinin, a sesquiterpene lactone widely used in malaria treatment. Amorpha-4,11-diene synthase （ADS）, a sesquiterpene synthase, and CYP71AV1, a P450 monooxygenase, are two key enzymes of the artemisinin biosynthesis pathway. Accumulation of artemisinin can be induced by the phytohormone jasmonate （JA）. Here, we report the characterization of two JA-responsive AP2 family transcription factors-AaERF1 and AaERF2-from A. annua L. Both genes were highly expressed in inflorescences and strongly induced by JA. Yeast one- hybrid and electrophoretic mobility shift assay （EMSA） showed that they were able to bind to the CRTDREHVCBF2 （CBF2） and RAVlAAT （RAA） motifs present in both ADS and CYP71AV1 promoters. Transient expression of either AaERF1 or AaERF2 in tobacco induced the promoter activities of ADS or CYP71AV1, and the transgenic A. annua plants overexpressing either transcription factor showed elevated transcript levels of both ADS and CYP71AV1, resulting in increased accumulation of artemisinin and artemisinic acid. By contrast, the contents of these two metabolites were reduced in the RNAi transgenic lines in which expression of AaERF1 or AaERF2 was suppressed. These results demonstrate that AaERF1 and AaERF2 are two positive regulators of artemisinin biosynthesis and are of great value in genetic engineering of arte- misinin production.
基金supported by the National Natural Science Foundation of China(31801074,31788103)。
文摘Apart from their primordial role in protein synthesis,t RNAs can be cleaved to produce t RNA-derived small RNAs(ts RNAs).The biological functions of ts RNAs in plants remain largely unknown.In this study,we developed Rtc B ligation-based small RNA(s RNA)sequencing,a method that captures and distinguishes between 3′-2′,3′-cyclic-phosphate(c P)/phosphate(P)-terminated s RNAs and 3′-OH-terminated s RNAs,and profiled 5′ts RNAs and 5′t RNA halves in Arabidopsis thaliana.We found that Arabidopsis 5′ts RNAs and 5′t RNA halves predominantly contain a c P at the 3′end and require S-like RNase 1(RNS1)and RNS3 for their production.One of the most abundant 5′ts RNAs,5′ts R-Ala,by associating with AGO1,negatively regulates Cytochrome P45071 A13(CYP71 A13)expression and camalexin biosynthesis to repress anti-fungal defense.Interestingly,5′ts R-Ala is downregulated upon fungal infection.Our study provides a global view of 5′ts RNAs and 5′t RNA halves in Arabidopsis and unravels an important role of a 5′ts RNA in regulating anti-fungal defense.
基金This study was supported by grants from the National Natural Science Foundation of China(No.30200358)the Doctorate Specialized Research Fund from China Ministry of Education(20070268008).
文摘An expressed sequence tag(EST)obtained from a subtractive-suppression hybridization cDNA library constructed using Catharanthus roseus cell line C_(20)hi and its parental cell line C_(20)D was used to clone a ful-length cytochrome P450 cDNA of cyp71d1.The encoded polypeptide contained 507 amino acids with 39-56% identity to other CYP7ID subfamily members at the.amino acid level.Expression characteristics of cyp71d1 were determined using semi-quantitative RT-PCR.The cyp71d1 transcript was expressed in all three cell lines with the highest level in the cell line C_(20)hi.In the mature C.roseus plant,the cyp71d1 cDNA was highly expressed in petals,roots and stems,but very weakly expressed in young leaves.Its transcription level increased with the development of flowers.2,4-D could down-regulate the transcription of cyp71d1,as did KT,but only to a minor degree.Neither light nor yeast elicitor could induce the transcription of cyp71d1.
