AIM: To investigate the differentiated whole genome expression profiling of gastric high- and low-grade intraepithelial neoplasia and early-stage adenocarcinoma.
Background:Muscle is the complex and heterogeneous tissue,which comprises the primary edible part of the trunk of fish and mammals.Previous studies have shown that dietary isoleucine(Ile)exerts beneficial effects on g...Background:Muscle is the complex and heterogeneous tissue,which comprises the primary edible part of the trunk of fish and mammals.Previous studies have shown that dietary isoleucine(Ile)exerts beneficial effects on growth in aquatic animals.However,there were limited studies regarding the benefits of Ile on fish muscle and their effects on flesh quality and muscle growth.Thus,this study was conducted to explore whether dietary Ile had affected flesh quality and muscle growth in hybrid bagrid catfish(Pelteobagrus vachelli♀×Leiocassis longirostris♂).Methods:A total of 630 hybrid fish,with an initial average body weight of 33.11±0.09 g,were randomly allotted into seven experimental groups with three replicates each,and respectively fed seven diets with 5.0,7.5,10.0,12.5,15.0,17.5,and 20.0 g Ile/kg diets for 8 weeks.Results:In the present study,we demonstrated that Ile significantly:(1)increased muscle protein and lipid contents and the frequency distribution of myofibers with≤20μm and≥50μm of diameter;(2)improved pH value,shear force,cathepsin B and L activities,hydroxyproline content,resilience,cohesiveness,and decreased cooking loss,lactate content,hardness,springiness,gumminess,and chewiness;(3)decreased reactive oxygen species(ROS),malondialdehyde(MDA),and protein carbonyl(PC)contents,GCLC and Keap1 mRNA levels,and up-regulated CuZnSOD,CAT,GPX1a,GST,and Nrf2 mRNA levels;(4)up-regulated the insulin-like growth factor 1,2(IGF-1,IGF-2),insulin-like growth factor 1 receptor(IGF-1R),proliferating cell nuclear antigen(PCNA),Myf5,Myod,Myog,Mrf4,and MyHC mRNA levels,and decreased MSTN mRNAlevel;(5)increased muscle protein deposition by activating AKT-TOR-S6K1 and AKT-FOXO3a signaling pathways.Conclusion:These results revealed that dietary Ile improved flesh quality,which might be due to increasing nutritional content,physicochemical,texture parameters,and antioxidant ability;promoting muscle growth by affecting myocytes hyperplasia and hypertrophy,and muscle protein deposition associated with protein synthesis and degradation signaling pathways.Finally,the quadratic regression analysis of chewiness,ROS,and protein contents against dietary Ile levels suggested that the optimal dietary Ile levels for hybrid bagrid catfish was estimated to be 14.19,12.36,and 12.78 g/kg diet,corresponding to 36.59,31.87,and 32.96 g/kg dietary protein,respectively.展开更多
In Additive Manufacturing field,the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models.To improve the efficiency and reduce the slicing time,a parallel...In Additive Manufacturing field,the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models.To improve the efficiency and reduce the slicing time,a parallel algorithm has great advantages.However,traditional algorithms can't make full use of multi-core CPU hardware resources.In the paper,a fast parallel algorithm is presented to speed up data processing.A pipeline mode is adopted to design the parallel algorithm.And the complexity of the pipeline algorithm is analyzed theoretically.To evaluate the performance of the new algorithm,effects of threads number and layers number are investigated by a serial of experiments.The experimental results show that the threads number and layers number are two remarkable factors to the speedup ratio.The tendency of speedup versus threads number reveals a positive relationship which greatly agrees with the Amdahl's law,and the tendency of speedup versus layers number also keeps a positive relationship agreeing with Gustafson's law.The new algorithm uses topological information to compute contours with a parallel method of speedup.Another parallel algorithm based on data parallel is used in experiments to show that pipeline parallel mode is more efficient.A case study at last shows a suspending performance of the new parallel algorithm.Compared with the serial slicing algorithm,the new pipeline parallel algorithm can make full use of the multi-core CPU hardware,accelerate the slicing process,and compared with the data parallel slicing algorithm,the new slicing algorithm in this paper adopts a pipeline parallel model,and a much higher speedup ratio and efficiency is achieved.展开更多
Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen...Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen of grass carp(Ctenopharyngodon idella)with Aeromonas hydrophila infection.Methods A total of 540 grass carp were used for the study.They were administered six gradient dosages of the MOS diet(0,200,400,600,800,and 1,000 mg/kg)for 60 d.Subsequently,we performed a 14-day Aeromonas hydrophila challenge experiment.The antioxidant capacity of the head kidney and spleen were examined using spectrophotometry,DNA fragmentation,qRT-PCR,and Western blotting.Results After infection with Aeromonas hydrophila,400-600 mg/kg MOS supplementation decreased the levels of reactive oxygen species,protein carbonyl,and malonaldehyde and increased the levels of anti-superoxide anion,antihydroxyl radical,and glutathione in the head kidney and spleen of grass carp.The activities of copper-zinc superoxide dismutase,manganese superoxide dismutase,catalase,glutathione S-transferase,glutathione reductase,and glutathione peroxidase were also enhanced by supplementation with 400-600 mg/kg MOS.Furthermore,the expression of most antioxidant enzymes and their corresponding genes increased significantly with supplementation of 200-800 mg/kg MOS.mRNA and protein levels of nuclear factor erythroid 2-related factor 2 also increased following supplementation with 400-600 mg/kg MOS.In addition,supplementation with 400-600 mg/kg MOS reduced excessive apoptosis by inhibiting the death receptor pathway and mitochondrial pathway processes.Conclusions Based on the quadratic regression analysis of the above biomarkers(reactive oxygen species,malondialdehyde,and protein carbonyl)of oxidative damage in the head kidney and spleen of on-growing grass carp,the recommended MOS supplementation is 575.21,557.58,531.86,597.35,570.16,and 553.80 mg/kg,respectively.Collectively,MOS supplementation could alleviate oxidative injury in the head kidney and spleen of grass carp infected with Aeromonas hydrophila.展开更多
Zearalenone(ZEA),a mycotoxin,poses a significant global hazard to human and animal health.Natural products(NPs)have shown promise for mitigating the adverse effects of ZEA owing to their diverse func-tional activities...Zearalenone(ZEA),a mycotoxin,poses a significant global hazard to human and animal health.Natural products(NPs)have shown promise for mitigating the adverse effects of ZEA owing to their diverse func-tional activities.However,the current challenge lies in the absence of an efficient strategy for systematic screening and identification of NPs that can effectively protect against ZEA-induced toxicity.This study describes a phenotype-based screening strategy for screening NP libraries and discovering more effective compounds to mitigate or counteract the adverse consequences of ZEA exposure in animals.Using this strategy,we initially identified 96 NPs and evaluated the potency and efficacy of two effective candidate compounds,fraxetin,and hydroxytyrosol,based on embryonic phenotype and locomotor activity using a scoring system and the TCMacro method.Furthermore,we performed transcriptome and proteinprotein interaction(PPI)network analyses to extract two mRNA signatures to query the Connectivity Map(CMap)database and predict NPs.The predicted NPs showed the potential to reverse the gene expression profiles associated with ZEA toxicity.Consequently,we further screened these compounds using our model,which indicated that hispidin,daphnetin,and riboflavin exhibit promising in vivo effi-cacy in zebrafish.Notably,throughout the process,fraxetin consistently stood out as the most promising NP.Biological pathway analysis and functional verification revealed that fraxetin completely reversed the toxic effects of ZEA at very low doses.This was achieved by repairing damaged cell apoptosis,modifying the cell cycle pathway,and preventing senescence induction,indicating good application potential.Overall,we demonstrated that this integration strategy can be successfully applied to effectively discover potential antidotes.展开更多
Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA a...Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA and the potential relieving strategy of natural products remain unclear.This study screened the substance curcumin(Cur),which had the best effect in alleviating OTA inhibition of myoblast proliferation,from 96 natural products and investigated its effect and mechanism in reducing OTA myotoxicity in vivo and in vitro.Methods A total of 720 healthy juvenile grass carp,with an initial average body weight of 11.06±0.05 g,were randomly assigned into 4 groups:the control group(without OTA and Cur),1.2 mg/kg OTA group,400 mg/kg Cur group,and 1.2 mg/kg OTA+400 mg/kg Cur group.Each treatment consisted of 3 replicates(180 fish)for 60 d.Results Firstly,we cultured,purified,and identified myoblasts using the tissue block culture method.Through preliminary screening and re-screening of 96 substances,we examined cell proliferation-related indicators such as cell viability and ultimately found that Cur had the best effect.Secondly,Cur could alleviate OTA-inhibited myoblast differentiation and myofibrillar development-related proteins(Myo G and MYHC)in vivo and in vitro and improve the growth performance of grass carp.Then,Cur could also promote the expression of OTA-inhibited protein synthesis-related proteins(S6K1 and TOR),which was related to the activation of the AKT/TOR signaling pathway.Finally,Cur could downregulate the expression of OTA-enhanced protein degradation-related genes(murf1,foxo3a,and ub),which was related to the inhibition of the Fox O3a signaling pathway.Conclusions In summary,our data demonstrated the effectiveness of Cur in alleviating OTA myotoxicity in vivo and in vitro.This study confirms the rapidity,feasibility,and effectiveness of establishing a natural product screening method targeting myoblasts to alleviate fungal toxin toxicity.展开更多
A higher β-glucosidase-producing strain was isolated and identified as Tolypocladium cylindrosporum syzx4 based on its morphology and internal transcribed spacer（ITS） rDNA gene sequence.The present study is to ferm...A higher β-glucosidase-producing strain was isolated and identified as Tolypocladium cylindrosporum syzx4 based on its morphology and internal transcribed spacer（ITS） rDNA gene sequence.The present study is to ferment,purify and characterize a β-glucosidase from T.cylindrosporum gams.The enzyme was purified to homogeneity by sulfate precipitataion,diethylaminoethyl cellulose anion exchange chromatography and Sephadex G-100 gel filtration with a 9.47-fold increase in specific activity and a recovery of 12.27%.The molecular weight（Mw） of the β-glucosidase was estimated to be 58600 by SDS-PAGE,which is much lower than that of the enzyme from other fungi.The β-glucosidase shows high activity over a wide range of temperature from 35℃ to 70℃ and the optimum pH is approximately 2.4.Then the kinetic parameters Km（0.85 mmol/L） and vmax[85.23 mmol/（L·s）] of the β-glucosidase were studied,respectively with high affinity p-nitrophenyl-β-D-glucopyranoside（p-NPG） as the substrate,inhibition constant Ki（39.5 mmol/L） with the tolerance of glucose.Although β-glucosidases have been purified and characterized from several other sources,T.cylindrosporum β-glucosidase with the unique optimal pH and higher tolerance of glucose distinguished from others makes the β-glucosidase a potential application in simultaneous saccharification and fermentation（SSF）.展开更多
The thermocline-sea surface temperature(SST)feedback is the most important component of the Bjerknes feedback,which plays an important role in the development of the air-sea coupling modes of the Indian Ocean.The ther...The thermocline-sea surface temperature(SST)feedback is the most important component of the Bjerknes feedback,which plays an important role in the development of the air-sea coupling modes of the Indian Ocean.The thermocline-SST feedback in the Indian Ocean has experienced significant decadal variations over the last40 a.The feedback intensified in the late twentieth century and then weakened during the hiatus in global warming at the early twenty-first century.The thermocline-SST feedback is most prominent in the southeastern and southwestern Indian Ocean.Although the decadal variations of feedback are similar in these two regions,there are still differences in the underlying mechanisms.The decadal variations of feedback in the southeastern Indian Ocean are dominated by variations in the depth of the thermocline,which are modulated by equatorial zonal wind anomalies.Whereas the decadal variation of feedback in the southwestern Indian Ocean is mainly controlled by the intensity of upwelling and thermocline depth in winter and spring,respectively.The upwelling and thermocline depth are both affected by wind stress curl anomalies over the southeastern Indian Ocean,which excite anomalous Ekman pumping and influence the southwestern Indian Ocean through westward propagating Rossby waves.展开更多
Populus alba‘Berolinensis’is a fast-growing,high-yielding species with strong biotic and abiotic stress resistance,and widely planted for timber,shelter belts and aesthetic purposes.In this study,molecular developme...Populus alba‘Berolinensis’is a fast-growing,high-yielding species with strong biotic and abiotic stress resistance,and widely planted for timber,shelter belts and aesthetic purposes.In this study,molecular development is explored and the important genes regulating xylem forma-tion in P.alba‘Berolinensis’under artificial bending treat-ments was identified.Anatomical investigation indicated that tension wood(TW)was characterized by eccentric growth of xylem and was enriched in cellulose;the degree of ligni-fication was lower than for normal wood(NW)and oppo-site wood(OW).RNA-Seq-based transcriptome analysis was performed using developing xylem from three wood types(TW,OW and NW).A large number of differentially expressed genes(DEGs)were screened and 4889 counted.In GO and KEGG enrichment results,genes involved in plant hormone signal transduction,phenylpropanoid biosynthesis,and cell wall and secondary cell wall biogenesis play major roles in xylem development under artificial bending.Eight expansin(PalEXP)genes were identified from the RNA-seq data;four were differentially expressed during tension wood formation.Phylogenetic analysis indicated that PalEXLB1 belongs to the EXPB subfamily and that the other PalEXPs are members of the EXPA subfamily.A transcriptional regulatory network construction showed 10 transcription factors located in the first and second layers upstream of EXP,including WRKY,ERF and bHLH.RT‒qPCR analy-sis in leaves,stems and roots combined with transcriptome analysis suggests that PalEXPA2,PalEXPA4 and PalEXPA15 play significant regulatory roles in cell wall formation during tension wood development.The candidate genes involved in xylem cell wall development during tension wood formation marks an important step toward identifying the molecular regulatory mechanism of xylem development and wood property improvement in P.alba‘Berolinensis’.展开更多
基金Supported by The specific grants of Public-Funded Projects in the Health Industry,Grant 200902002
文摘AIM: To investigate the differentiated whole genome expression profiling of gastric high- and low-grade intraepithelial neoplasia and early-stage adenocarcinoma.
基金supported by National Key R&D Program of China(2019YFD0900200)the Applied Basic Research Programs of ScienceTechnology Commission Foundation of Sichuan Province,China(2015JY0067).
文摘Background:Muscle is the complex and heterogeneous tissue,which comprises the primary edible part of the trunk of fish and mammals.Previous studies have shown that dietary isoleucine(Ile)exerts beneficial effects on growth in aquatic animals.However,there were limited studies regarding the benefits of Ile on fish muscle and their effects on flesh quality and muscle growth.Thus,this study was conducted to explore whether dietary Ile had affected flesh quality and muscle growth in hybrid bagrid catfish(Pelteobagrus vachelli♀×Leiocassis longirostris♂).Methods:A total of 630 hybrid fish,with an initial average body weight of 33.11±0.09 g,were randomly allotted into seven experimental groups with three replicates each,and respectively fed seven diets with 5.0,7.5,10.0,12.5,15.0,17.5,and 20.0 g Ile/kg diets for 8 weeks.Results:In the present study,we demonstrated that Ile significantly:(1)increased muscle protein and lipid contents and the frequency distribution of myofibers with≤20μm and≥50μm of diameter;(2)improved pH value,shear force,cathepsin B and L activities,hydroxyproline content,resilience,cohesiveness,and decreased cooking loss,lactate content,hardness,springiness,gumminess,and chewiness;(3)decreased reactive oxygen species(ROS),malondialdehyde(MDA),and protein carbonyl(PC)contents,GCLC and Keap1 mRNA levels,and up-regulated CuZnSOD,CAT,GPX1a,GST,and Nrf2 mRNA levels;(4)up-regulated the insulin-like growth factor 1,2(IGF-1,IGF-2),insulin-like growth factor 1 receptor(IGF-1R),proliferating cell nuclear antigen(PCNA),Myf5,Myod,Myog,Mrf4,and MyHC mRNA levels,and decreased MSTN mRNAlevel;(5)increased muscle protein deposition by activating AKT-TOR-S6K1 and AKT-FOXO3a signaling pathways.Conclusion:These results revealed that dietary Ile improved flesh quality,which might be due to increasing nutritional content,physicochemical,texture parameters,and antioxidant ability;promoting muscle growth by affecting myocytes hyperplasia and hypertrophy,and muscle protein deposition associated with protein synthesis and degradation signaling pathways.Finally,the quadratic regression analysis of chewiness,ROS,and protein contents against dietary Ile levels suggested that the optimal dietary Ile levels for hybrid bagrid catfish was estimated to be 14.19,12.36,and 12.78 g/kg diet,corresponding to 36.59,31.87,and 32.96 g/kg dietary protein,respectively.
文摘In Additive Manufacturing field,the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models.To improve the efficiency and reduce the slicing time,a parallel algorithm has great advantages.However,traditional algorithms can't make full use of multi-core CPU hardware resources.In the paper,a fast parallel algorithm is presented to speed up data processing.A pipeline mode is adopted to design the parallel algorithm.And the complexity of the pipeline algorithm is analyzed theoretically.To evaluate the performance of the new algorithm,effects of threads number and layers number are investigated by a serial of experiments.The experimental results show that the threads number and layers number are two remarkable factors to the speedup ratio.The tendency of speedup versus threads number reveals a positive relationship which greatly agrees with the Amdahl's law,and the tendency of speedup versus layers number also keeps a positive relationship agreeing with Gustafson's law.The new algorithm uses topological information to compute contours with a parallel method of speedup.Another parallel algorithm based on data parallel is used in experiments to show that pipeline parallel mode is more efficient.A case study at last shows a suspending performance of the new parallel algorithm.Compared with the serial slicing algorithm,the new pipeline parallel algorithm can make full use of the multi-core CPU hardware,accelerate the slicing process,and compared with the data parallel slicing algorithm,the new slicing algorithm in this paper adopts a pipeline parallel model,and a much higher speedup ratio and efficiency is achieved.
基金financially supported by the National Key R&D Program of China(2019YFD0900200,2018YFD0900400)Supported by the earmarked fund for CARS(CARS-45)+2 种基金National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)the Young Top-Notch Talent Support ProgramSichuan Science and Technology Program(2019YFN0036)。
文摘Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen of grass carp(Ctenopharyngodon idella)with Aeromonas hydrophila infection.Methods A total of 540 grass carp were used for the study.They were administered six gradient dosages of the MOS diet(0,200,400,600,800,and 1,000 mg/kg)for 60 d.Subsequently,we performed a 14-day Aeromonas hydrophila challenge experiment.The antioxidant capacity of the head kidney and spleen were examined using spectrophotometry,DNA fragmentation,qRT-PCR,and Western blotting.Results After infection with Aeromonas hydrophila,400-600 mg/kg MOS supplementation decreased the levels of reactive oxygen species,protein carbonyl,and malonaldehyde and increased the levels of anti-superoxide anion,antihydroxyl radical,and glutathione in the head kidney and spleen of grass carp.The activities of copper-zinc superoxide dismutase,manganese superoxide dismutase,catalase,glutathione S-transferase,glutathione reductase,and glutathione peroxidase were also enhanced by supplementation with 400-600 mg/kg MOS.Furthermore,the expression of most antioxidant enzymes and their corresponding genes increased significantly with supplementation of 200-800 mg/kg MOS.mRNA and protein levels of nuclear factor erythroid 2-related factor 2 also increased following supplementation with 400-600 mg/kg MOS.In addition,supplementation with 400-600 mg/kg MOS reduced excessive apoptosis by inhibiting the death receptor pathway and mitochondrial pathway processes.Conclusions Based on the quadratic regression analysis of the above biomarkers(reactive oxygen species,malondialdehyde,and protein carbonyl)of oxidative damage in the head kidney and spleen of on-growing grass carp,the recommended MOS supplementation is 575.21,557.58,531.86,597.35,570.16,and 553.80 mg/kg,respectively.Collectively,MOS supplementation could alleviate oxidative injury in the head kidney and spleen of grass carp infected with Aeromonas hydrophila.
基金supported by the National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)the National Key Research and Development(R&D)Program of China(2018YFD0900400)the Young Top-Notch Talent Support Program and Government Guidance for Local Scientific and Technological Development Projects(23ZYZYTS0513).
文摘Zearalenone(ZEA),a mycotoxin,poses a significant global hazard to human and animal health.Natural products(NPs)have shown promise for mitigating the adverse effects of ZEA owing to their diverse func-tional activities.However,the current challenge lies in the absence of an efficient strategy for systematic screening and identification of NPs that can effectively protect against ZEA-induced toxicity.This study describes a phenotype-based screening strategy for screening NP libraries and discovering more effective compounds to mitigate or counteract the adverse consequences of ZEA exposure in animals.Using this strategy,we initially identified 96 NPs and evaluated the potency and efficacy of two effective candidate compounds,fraxetin,and hydroxytyrosol,based on embryonic phenotype and locomotor activity using a scoring system and the TCMacro method.Furthermore,we performed transcriptome and proteinprotein interaction(PPI)network analyses to extract two mRNA signatures to query the Connectivity Map(CMap)database and predict NPs.The predicted NPs showed the potential to reverse the gene expression profiles associated with ZEA toxicity.Consequently,we further screened these compounds using our model,which indicated that hispidin,daphnetin,and riboflavin exhibit promising in vivo effi-cacy in zebrafish.Notably,throughout the process,fraxetin consistently stood out as the most promising NP.Biological pathway analysis and functional verification revealed that fraxetin completely reversed the toxic effects of ZEA at very low doses.This was achieved by repairing damaged cell apoptosis,modifying the cell cycle pathway,and preventing senescence induction,indicating good application potential.Overall,we demonstrated that this integration strategy can be successfully applied to effectively discover potential antidotes.
基金financially supported by the earmarked fund for CARS(CARS-45)National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)+1 种基金the Young Top-Notch Talent Support Programthe 111 project(D17015)。
文摘Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA and the potential relieving strategy of natural products remain unclear.This study screened the substance curcumin(Cur),which had the best effect in alleviating OTA inhibition of myoblast proliferation,from 96 natural products and investigated its effect and mechanism in reducing OTA myotoxicity in vivo and in vitro.Methods A total of 720 healthy juvenile grass carp,with an initial average body weight of 11.06±0.05 g,were randomly assigned into 4 groups:the control group(without OTA and Cur),1.2 mg/kg OTA group,400 mg/kg Cur group,and 1.2 mg/kg OTA+400 mg/kg Cur group.Each treatment consisted of 3 replicates(180 fish)for 60 d.Results Firstly,we cultured,purified,and identified myoblasts using the tissue block culture method.Through preliminary screening and re-screening of 96 substances,we examined cell proliferation-related indicators such as cell viability and ultimately found that Cur had the best effect.Secondly,Cur could alleviate OTA-inhibited myoblast differentiation and myofibrillar development-related proteins(Myo G and MYHC)in vivo and in vitro and improve the growth performance of grass carp.Then,Cur could also promote the expression of OTA-inhibited protein synthesis-related proteins(S6K1 and TOR),which was related to the activation of the AKT/TOR signaling pathway.Finally,Cur could downregulate the expression of OTA-enhanced protein degradation-related genes(murf1,foxo3a,and ub),which was related to the inhibition of the Fox O3a signaling pathway.Conclusions In summary,our data demonstrated the effectiveness of Cur in alleviating OTA myotoxicity in vivo and in vitro.This study confirms the rapidity,feasibility,and effectiveness of establishing a natural product screening method targeting myoblasts to alleviate fungal toxin toxicity.
基金Supported by the Important Agriculture Program of the Jilin Province Technology Department,China(No.20096013)the Jilin University Basic Science Research Fund,China(No.200903259)+1 种基金the Graduate Innovation Fund of Jilin University,China (No.20101043)the Project of Jilin Fuel Alcohol Company Ltd.,China
文摘A higher β-glucosidase-producing strain was isolated and identified as Tolypocladium cylindrosporum syzx4 based on its morphology and internal transcribed spacer（ITS） rDNA gene sequence.The present study is to ferment,purify and characterize a β-glucosidase from T.cylindrosporum gams.The enzyme was purified to homogeneity by sulfate precipitataion,diethylaminoethyl cellulose anion exchange chromatography and Sephadex G-100 gel filtration with a 9.47-fold increase in specific activity and a recovery of 12.27%.The molecular weight（Mw） of the β-glucosidase was estimated to be 58600 by SDS-PAGE,which is much lower than that of the enzyme from other fungi.The β-glucosidase shows high activity over a wide range of temperature from 35℃ to 70℃ and the optimum pH is approximately 2.4.Then the kinetic parameters Km（0.85 mmol/L） and vmax[85.23 mmol/（L·s）] of the β-glucosidase were studied,respectively with high affinity p-nitrophenyl-β-D-glucopyranoside（p-NPG） as the substrate,inhibition constant Ki（39.5 mmol/L） with the tolerance of glucose.Although β-glucosidases have been purified and characterized from several other sources,T.cylindrosporum β-glucosidase with the unique optimal pH and higher tolerance of glucose distinguished from others makes the β-glucosidase a potential application in simultaneous saccharification and fermentation（SSF）.
基金The National Natural Science Foundation of China under contract Nos 41976021,41676020,41876028 and41876030the Taishan Scholars Programs of Shandong Province under contract Nos tsqn201909165 and ts20190963the Global Change and Air-Sea Interaction Program under contract No.GASI-04-QYQH-03。
文摘The thermocline-sea surface temperature(SST)feedback is the most important component of the Bjerknes feedback,which plays an important role in the development of the air-sea coupling modes of the Indian Ocean.The thermocline-SST feedback in the Indian Ocean has experienced significant decadal variations over the last40 a.The feedback intensified in the late twentieth century and then weakened during the hiatus in global warming at the early twenty-first century.The thermocline-SST feedback is most prominent in the southeastern and southwestern Indian Ocean.Although the decadal variations of feedback are similar in these two regions,there are still differences in the underlying mechanisms.The decadal variations of feedback in the southeastern Indian Ocean are dominated by variations in the depth of the thermocline,which are modulated by equatorial zonal wind anomalies.Whereas the decadal variation of feedback in the southwestern Indian Ocean is mainly controlled by the intensity of upwelling and thermocline depth in winter and spring,respectively.The upwelling and thermocline depth are both affected by wind stress curl anomalies over the southeastern Indian Ocean,which excite anomalous Ekman pumping and influence the southwestern Indian Ocean through westward propagating Rossby waves.
基金funded by the Fundamental Research Funds for the Central Universities(2572019CT02)Heilongjiang Touyan Innovation Team Program(Tree Genetics and Breeding Innovation Team)The Overseas Expertise Introduction Project for Discipline Innovation(B16010).
文摘Populus alba‘Berolinensis’is a fast-growing,high-yielding species with strong biotic and abiotic stress resistance,and widely planted for timber,shelter belts and aesthetic purposes.In this study,molecular development is explored and the important genes regulating xylem forma-tion in P.alba‘Berolinensis’under artificial bending treat-ments was identified.Anatomical investigation indicated that tension wood(TW)was characterized by eccentric growth of xylem and was enriched in cellulose;the degree of ligni-fication was lower than for normal wood(NW)and oppo-site wood(OW).RNA-Seq-based transcriptome analysis was performed using developing xylem from three wood types(TW,OW and NW).A large number of differentially expressed genes(DEGs)were screened and 4889 counted.In GO and KEGG enrichment results,genes involved in plant hormone signal transduction,phenylpropanoid biosynthesis,and cell wall and secondary cell wall biogenesis play major roles in xylem development under artificial bending.Eight expansin(PalEXP)genes were identified from the RNA-seq data;four were differentially expressed during tension wood formation.Phylogenetic analysis indicated that PalEXLB1 belongs to the EXPB subfamily and that the other PalEXPs are members of the EXPA subfamily.A transcriptional regulatory network construction showed 10 transcription factors located in the first and second layers upstream of EXP,including WRKY,ERF and bHLH.RT‒qPCR analy-sis in leaves,stems and roots combined with transcriptome analysis suggests that PalEXPA2,PalEXPA4 and PalEXPA15 play significant regulatory roles in cell wall formation during tension wood development.The candidate genes involved in xylem cell wall development during tension wood formation marks an important step toward identifying the molecular regulatory mechanism of xylem development and wood property improvement in P.alba‘Berolinensis’.
