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Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications 被引量:5
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作者 Shuai Liu Jiang-Ming Yu +11 位作者 Yan-Chang Gan Xiao-Zhong Qiu Zhe-Chen Gao Huan Wang Shi-Xuan Chen Yuan Xiong Guo-Hui Liu Si-En Lin Alec McCarthy Johnson V.John Dai-Xu Wei Hong-Hao Hou 《Military Medical Research》 SCIE CAS CSCD 2024年第1期50-79,共30页
Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds bas... Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative medicine.This paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future challenges.We highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ECM.Moreover,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE applications.Finally,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field. 展开更多
关键词 Biomimic SCAFFOLD biosynthesis Natural biomaterial Tissue engineering
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OsFK1 encodes C-14 sterol reductase,which is involved in sterol biosynthesis and affects premature aging of leaves in rice
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作者 Ping Li Xia Zhang +15 位作者 Wuzhong Yin Yang Shui Jie Zhang Nana Xu Dasong Bai Qingxiong Huang Yuanyuan Li Pan Qi Xing Li Qianlong Li Shihong Yang Guotao Yang Hong Chen Peng Qin Yungao Hu Youlin Peng 《The Crop Journal》 SCIE CSCD 2024年第4期1010-1021,共12页
The enzyme C-14 sterol reductase is involved in biosynthesis of brassinosteroids(BR)and sterols,as well as plant development.OsFK1,a member of the sterol biosynthesis pathway located in the endoplasmic reticulum(ER),e... The enzyme C-14 sterol reductase is involved in biosynthesis of brassinosteroids(BR)and sterols,as well as plant development.OsFK1,a member of the sterol biosynthesis pathway located in the endoplasmic reticulum(ER),encodes C-14 sterol reductase.However,there is little research on the function of C-14 sterol reductase in rice.Compared with the wild type,an osfk1 mutant showed dwarf phenotype and premature aging in the second leaf during the trefoil stage,and abnormal development of leaf veins during the tillering stage.The osfk1 mutant showed signs of aberrant PCD,as evidenced by TUNEL staining.This suggested that high ROS buildup caused DNA damage and ROS-mediated cell death in the mutant.The osfk1 mutant also showed decreased chlorophyll content and aberrant chloroplast structure.Sequencing of the osfk1 mutant allele revealed a non-synonymous G to A mutation in the final intron,leading to early termination.Here,we identified the OsFK1 allele,cloned it by Mutmap sequencing,and verified it by complementation.HPLC-MS/MS assays demonstrated that the osfk1 mutation caused lower phytosterol levels.These findings showed that the OsFK1 allele encoding C-14 sterol reductase is involved in phytosterol biosynthesis and mediates normal development of rice plants. 展开更多
关键词 Leaf development ROS Phytosterol biosynthesis RICE
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Chain Elongation Using Native Soil Inocula:Exceptional n-Caproate Biosynthesis Performance and Microbial Mechanisms
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作者 Lin Deng Yang Lv +5 位作者 Tian Lan Qing-Lian Wu Wei-Tong Ren Hua-Zhe Wang Bing-Jie Ni Wan-Qian Guo 《Engineering》 SCIE EI CAS CSCD 2024年第8期262-272,共11页
This study demonstrates the feasibility and effectiveness of utilizing native soils as a resource for inocula to produce n-caproate through the chain elongation(CE)platform,offering new insights into anaerobic soil pr... This study demonstrates the feasibility and effectiveness of utilizing native soils as a resource for inocula to produce n-caproate through the chain elongation(CE)platform,offering new insights into anaerobic soil processes.The results reveal that all five of the tested soil types exhibit CE activity when supplied with high concentrations of ethanol and acetate,highlighting the suitability of soil as an ideal source for n-caproate production.Compared with anaerobic sludge and pit mud,the native soil CE system exhibited higher selectivity(60.53%),specificity(82.32%),carbon distribution(60.00%),electron transfer efficiency(165.00%),and conductivity(0.59 ms∙cm^(-1)).Kinetic analysis further confirmed the superiority of soil in terms of a shorter lag time and higher yield.A microbial community analysis indicated a positive correlation between the relative abundances of Pseudomonas,Azotobacter,and Clostridium and n-caproate production.Moreover,metagenomics analysis revealed a higher abundance of functional genes in key microbial species,providing direct insights into the pathways involved in n-caproate formation,including in situ CO_(2)utilization,ethanol oxidation,fatty acid biosynthesis(FAB),and reverse beta-oxidation(RBO).The numerous functions in FAB and RBO are primarily associated with Pseudomonas,Clostridium,Rhodococcus,Stenotrophomonas,and Geobacter,suggesting that these genera may play roles that are involved or associated with the CE process.Overall,this innovative inoculation strategy offers an efficient microbial source for n-caproate production,underscoring the importance of considering CE activity in anaerobic soil microbial ecology and holding potential for significant economic and environmental benefits through soil consortia exploration. 展开更多
关键词 SOIL Chain elongation n-caproate Reverse beta-oxidation Fatty acid biosynthesis METAGENOMICS
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Rational Engineering of Secondary Metabolic Pathways in a Heterologous Host to Enable the Biosynthesis of Hibarimicin Derivatives with Enhanced Anti-Melanomic Activity
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作者 Xiangyang Liu Fei-Peng Zhao +9 位作者 Tian Tian Wei-Chen Wang Zaizhou Liu Qiang Zhou Xian-Feng Hou Jing Wang Wenli Guo Shuangjun Lin Yasuhiro Igarashi Gong-Li Tang 《Engineering》 SCIE EI CAS CSCD 2024年第7期113-123,共11页
A 61-kb biosynthetic gene cluster(BGC),which is accountable for the biosynthesis of hibarimicin(HBM)B from Microbispora rosea subsp.hibaria TP-A0121,was heterologously expressed in Streptomyces coelicolor M1154,which ... A 61-kb biosynthetic gene cluster(BGC),which is accountable for the biosynthesis of hibarimicin(HBM)B from Microbispora rosea subsp.hibaria TP-A0121,was heterologously expressed in Streptomyces coelicolor M1154,which generated a trace of the target products but accumulated a large amount of shunt products.Based on rational analysis of the relevant secondary metabolism,directed engineering of the biosynthetic pathways resulted in the high production of HBM B,as well as new HBM derivates with improved antitumor activity.These results not only establish a biosynthetic system to effectively synthesize HBMs-a class of the largest and most complex Type-Ⅱpolyketides,with a unique pseudo-dimeric structure-but also set the stage for further engineering and deep investigation of this complex biosynthetic pathway toward potent anticancer drugs. 展开更多
关键词 Hibarimicin biosynthesis Heterologous expression Biosynthetic gene cluster Rational engineering Type-II polyketide
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Wetting alternating with partial drying during grain filling increases lysine biosynthesis in inferior rice grain
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作者 Yi Jiang Wenli Tao +2 位作者 Weiyang Zhang Zhiqin Wang Jianchang Yang 《The Crop Journal》 SCIE CSCD 2024年第1期262-270,共9页
Lysine content is a criterion of the nutritional quality of rice.Understanding the process of lysine biosynthesis in early-flowering superior grain(SG)and late-flowering inferior grain(IG)of rice would advance breedin... Lysine content is a criterion of the nutritional quality of rice.Understanding the process of lysine biosynthesis in early-flowering superior grain(SG)and late-flowering inferior grain(IG)of rice would advance breeding and cultivation to improve nutritional quality.However,little information is available on differences in lysine anabolism between SG and IG and the underlying mechanism,and whether and how irrigation regimes affect lysine anabolism in these grains.A japonica rice cultivar was grown in the field and two irrigation regimes,continuous flooding(CF)and wetting alternating with partial drying(WAPD),were imposed from heading to the mature stage.Lysine content and activities of key enzymes of lysine biosynthesis,and levels of brassinosteroids(BRs)were lower in the IG than in the SG at the early grainfilling stage but higher at middle and late grain-filling stages.WAPD increased activities of these key enzymes,BR levels,and contents of lysine and total amino acids in IG,but not SG relative to CF.Application of 2,4-epibrassinolide to rice panicles in CF during early grain filling reproduced the effects of WAPD,but neither treatment altered the activities of enzymes responsible for lysine catabolism in either SG or IG.WAPD and elevated BR levels during grain filling increased lysine biosynthesis in IG.Improvement in lysine biosynthesis in rice should focus on IG. 展开更多
关键词 BRASSINOSTEROIDS Inferior grain Lysine biosynthesis Rice Wetting alternating with partial drying
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Transcriptome analysis reveals steroid hormones biosynthesis pathway involved in abdominal fat deposition in broilers
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作者 Yuting Zhu Yongli Wang +3 位作者 Yidong Wang Guiping Zhao Jie Wen Huanxian Cui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3118-3128,共11页
Excessive abdominal fat deposition reduces the feed efficiency and increase the cost of production in broilers.Therefore,it is an important task for poultry breeders to breed broilers with low abdominal fat.Abdominal ... Excessive abdominal fat deposition reduces the feed efficiency and increase the cost of production in broilers.Therefore,it is an important task for poultry breeders to breed broilers with low abdominal fat.Abdominal fat deposition is a highly complex biological process,and its molecular basis remains elusive.In this study,we performed transcriptome analysis to compare gene expression profiles at different stages of abdominal fat deposition to identify the key genes and pathways involved in abdominal fat accumulation.We found that abdominal fat weight(AFW)increased gradually from day 35(D35)to 91(D91),and then decreased at day 119(D119).Accordingly,after detecting differentially expressed genes(DEGs)by comparing gene expression profiles at D35 vs.D63 and D35 vs.D91,and identifying gene modules associated with fat deposition by weighted gene co-expression network analysis(WGCNA),we performed intersection analysis of the detected DEGs and WGCNA gene modules and identified 394 and 435 intersecting genes,respectively.The results of the Gene Ontology(GO)functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses showed that the steroid hormone biosynthesis and insulin signaling pathways were co-enriched in all intersecting genes,steroid hormones have been shown that regulated insulin signaling pathway,indicating the importance of the steroid hormone biosynthesis pathway in the development of broiler abdominal fat.We then identified 6 hub genes(ACTB,SOX9,RHOBTB2,PDLIM3,NEDD9,and DOCK4)related to abdominal fat deposition.Further analysis also revealed that there were direct interactions between 6 hub genes.SOX9 has been shown to bind to proteins required for steroid hormone receptor binding,and RHOBTB2 indirectly regulates the steroid hormones biosynthesis through cyclin factor,and ultimately affect fat deposition.Our results suggest that the genes RHOBTB2 and SOX9 play an important role in fat deposition in broilers,by regulating steroid hormone synthesis.These findings provide new targets and directions for further studies on the mechanisms of fat deposition in chicken. 展开更多
关键词 BROILERS abdominal fat deposition transcriptome analysis hub genes steroid hormones biosynthesis pathway
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Identification and Molecular Characterization of the Alkaloid Biosynthesis Gene Family in Dendrobium catenatum
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作者 Liping Yang Xin Wan +1 位作者 Runyang Zhou Yingdan Yuan 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第1期81-96,共16页
As one of the main active components of Dendrobium catenatum, alkaloids have high medicinal value. The physicochemicalproperties, conserved domains and motifs, phylogenetic analysis, and cis-acting elements of the gen... As one of the main active components of Dendrobium catenatum, alkaloids have high medicinal value. The physicochemicalproperties, conserved domains and motifs, phylogenetic analysis, and cis-acting elements of the genefamily members in the alkaloid biosynthesis pathway of D. catenatum were analyzed by bioinformatics, and theexpression of the genes in different years and tissues was analyzed by qRT-PCR. There are 16 gene families,including 25 genes, in the D. catenatum alkaloid biosynthesis pathway. The analysis of conserved domains andmotifs showed that the types, quantities, and orders of domains and motifs were similar among members ofthe same family, but there were significant differences among families. Phylogenetic analysis indicated that thegene family members showed some evolutionary conservation. Cis-acting element analysis revealed that therewere a large number of light-responsive elements and MYB (v-myb avian myeloblastosis viral oncogene homolog)-related elements in these genes. qRT-PCR showed that expressions of gene family members involved in alkaloidsynthesis were different in different years and tissues of D. catenatum. This study provides a theoretical basisfor further exploration of the regulatory mechanisms of these genes in the alkaloid biosynthesis of D. catenatum. 展开更多
关键词 Dendrobium catenatum gene family alkaloid biosynthesis
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Research Progress on Functions and Biosynthesis of D-Psicose
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作者 Zhe FENG Pan DENG +1 位作者 Yuehan LIU Junqing WANG 《Agricultural Biotechnology》 2024年第3期55-59,63,共6页
D-Psicose,a naturally occurring rare sugar,exhibits a sweetness approximately 70%that of sucrose.It possesses high solubility,antioxidant activity,anti-inflammatory properties,and the ability to regulate cholesterol l... D-Psicose,a naturally occurring rare sugar,exhibits a sweetness approximately 70%that of sucrose.It possesses high solubility,antioxidant activity,anti-inflammatory properties,and the ability to regulate cholesterol levels and enhance insulin sensitivity.However,D-psicose is relatively scarce in nature,making large-scale extraction and utilization impractical.Consequently,the development of cost-effective synthetic strategies for D-psicose is pivotal for its industrial application.In recent years,the Izumoring strategy has emerged as an efficient alternative to chemical synthesis for producing D-psicose.Nonetheless,limitations in the biotransformation of D-psicose,primarily governed by the conversion rate of D-psicose 3-epimerase(DPEase)and enzyme yield,continue to pose challenges in achieving economically viable production.Enzyme engineering and the establishment of high-level expression systems remain crucial avenues for reducing the overall biosynthesis costs. 展开更多
关键词 D-Psicose biosynthesis High-throughput screening
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The biosynthesis of alarm pheromone in the wheat aphid Rhopalosiphum padi is regulated by hormones via fatty acid metabolism
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作者 Chengxian Sun Yaoguo Qin +1 位作者 Julian Chen Zhengxi Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2346-2361,共16页
Aphids are major insect pests in agriculture and forestry worldwide.Following attacks by natural enemies,many aphids release an alarm pheromone to protect their population.In most aphids,the main component of the aphi... Aphids are major insect pests in agriculture and forestry worldwide.Following attacks by natural enemies,many aphids release an alarm pheromone to protect their population.In most aphids,the main component of the aphid alarm pheromone(AAP)is the sesquiterpene hydrocarbon(E)-β-farnesene(EβF).However,the mechanisms behind its biosynthesis and regulation remain poorly understood.In this study,we used the bird cherry–oat aphid Rhopalosiphum padi,which is an important wheat aphid,to investigate the regulatory mechanisms of EβF biosynthesis.Our results showed that EβF biosynthesis occurs during the mature embryo period and the molting period of the 1st-and 2nd-instar nymphs.Triglycerides provide the prerequisite material for EβF production and release.Based on transcriptome sequencing,RNAi analysis,hormone treatments,and quantitative measurements,we found that the biosynthesis of EβF utilizes acetyl coenzyme A produced from fatty acid degradation,which can be suppressed by juvenile hormone but it is promoted by 20-hydroxyecdysone through the modulation of fatty acid metabolism.This is the first systemic study on the modulation of EβF production in aphids.The results of our study provide insights into the molecular regulatory mechanisms of AAP biosynthesis,as well as valuable information for designing potential aphid control strategies. 展开更多
关键词 (E)-β-farnesene critical period for biosynthesis fatty acid metabolism juvenile hormone 20-HYDROXYECDYSONE
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Biosynthesis of Silver Nanoparticles with Clerodendron phlomoides Leave Extract:Particle Morphology,Antimicrobial Potential and Application
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作者 Kirubanandan Shanmugam Subha Veeramani Renganathan Sahadevan 《Journal of Clinical and Nursing Research》 2024年第1期51-64,共14页
Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides... Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides leaves extract has been found to contain various phytochemicals,such as phenols,flavonoids,tannins,and alkaloids,which possess reducing and stabilizing properties that can aid the production of silver particles.In this paper,morphological and topographical analyses were performed on silver nanoparticles.The biosynthesized silver nanoparticles showed antimicrobial potential against wound pathogens.SEM and TEM micrographs revealed that the particles were sphere and nanosized,which makes them suitable for various biomedical applications. 展开更多
关键词 Silver nanoparticles Clerodendron phlomoides biosynthesis Morphology SEM TEM FTIR Antimicrobial activity and wound pathogens
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The Chlorophyll Biosynthesis in Lotus Embryo Is Light-dependent 被引量:9
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作者 季宏伟 李良璧 匡廷云 《Acta Botanica Sinica》 CSCD 2001年第7期693-698,共6页
Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the covera... Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the coverage of four layers of integuments (cotyledon, seed coat, pericarp, lotus pod) which were thought impossible for light to pass through. The authors excluded this possibility based on two experimental results: First, enclosing the young lotus pod with aluminium foil, the growth of louts embryo continued, but the chlorophyll formation was seriously inhibited. A lot of protochlorophyllide, chlorophyll precursor, were accumulated, most of which were combined with LPOR (light dependent protochlorophyllide oxidoreductase). Second, DPOR (dark or light-independent protochlorophyllide oxidoreductase) was the enzyme necessary for chlorophyll synthesis in the dark. The genes encoding DPOR were conservative in many species, but no homologues could be found in lotus genome. Taken together, authers' results clearly demonstrated that lotus embryo synthesizes chlorophyll only through the light-dependent pathway. 展开更多
关键词 lotus embryo chlorophyll biosynthesis protochlorophyllide oxidoreductase
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Advances in Trehalose Biosynthesis Pathways and Application of Molecular Biology Technique 被引量:4
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作者 巩涛 李琳琳 +1 位作者 赵正中 刘德海 《Agricultural Science & Technology》 CAS 2016年第8期1790-1795,共6页
This paper aims to provide better guidance for construction of trehalose-producing recombinant strains to further improve the yield of trehalose. The research progress on trehalose biosynthesis pathways and the applic... This paper aims to provide better guidance for construction of trehalose-producing recombinant strains to further improve the yield of trehalose. The research progress on trehalose biosynthesis pathways and the application of molecular biology technique in trehalose study in recent 30 years, especially the last 10 years are reviewed. Results show that there are 5 pathways of trehalose synthesis. Although enzymes and genes of trehalose synthesis have been isolated and genetic engineering strains have increased gradually, the improvement of trehalose yield is still inadequate because most recombinant strains are limited to study the physicochemical properties of single enzyme. With the development of modern biological technology, especially the rapid development of DNA recombinant technology, metagenomics and synthetic biology, high expression of heterologous trehalose in recombinant strains would become a hot research topic in the future. 展开更多
关键词 TREHALOSE biosynthesis pathway DNA recombination technology METAGENOMICS
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OsHemA gene, encoding glutamyl-tRNA reductase(GluTR) is essential for chlorophyll biosynthesis in rice(Oryza sativa) 被引量:15
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作者 ZENG Zhao-qiong LIN Tian-zi +7 位作者 ZHAO Jie-yu ZHENG Tian-hui XU Le-feng WANG Yi-hua LIU Ling-long JIANG Ling CHEN Sai-hua WAN Jian-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第3期612-623,共12页
Chlorophyll(Chl) biosynthesis is essential for photosynthesis and plant growth.Glutamyl-tRNA reductase(GluTR) catalyzes glutamyl-tRNA into glutamate-1-semialdehyde(GSA) and initiates the chlorophyll biosynthesis.Even ... Chlorophyll(Chl) biosynthesis is essential for photosynthesis and plant growth.Glutamyl-tRNA reductase(GluTR) catalyzes glutamyl-tRNA into glutamate-1-semialdehyde(GSA) and initiates the chlorophyll biosynthesis.Even though the main role of GluTR has been established,the effects caused by natural variations in its corresponding gene remain largely unknown.Here,we characterized a spontaneous mutant in paddy field with Chl biosynthesis deficiency,designated as cbd1.With intact thylakoid lamellar structure,the cbd1 plant showed light green leaves and reduced Chl and carotenoids(Cars) content significantly compared to the wild type.By map-based gene cloning,the mutation was restricted within a 57-kb region on chromosome 10,in which an mPingA miniature inverted-repeat transposable element(MITE) inserted in the promoter region of OsHemA gene.Both leaf color and the pigment contents in cbd1 were recovered in a complementation test,confirming OsHemA was responsible for the mutant phenotype.OsHemA was uniquely predicted to encode GluTR and its expression level was dramatically repressed in cbd1.Transient transformation in protoplasts demonstrated that GluTR localized in chloroplasts and a signal peptide exists in its N-terminus.A majority of Chl biosynthesis genes,except for POR and CHLG,were down-regulated synchronously by the repression of OsHemA,suggesting that an attenuation occurred in the Chl biosynthesis pathway.Interestingly,we found major agronomic traits involved in rice yield were statistically unaffected,except for the number of full grains per panicle was increased in cbd1.Collectively,OsHemA plays an essential role in Chl biosynthesis in rice and its weak allele can adjust leaf color and Chls content without compromise to rice yield. 展开更多
关键词 OsHemA GluTR chlorophyll biosynthesis
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Effects of uniconazole with or without micronutrient on the lignin biosynthesis,lodging resistance,and winter wheat production in semiarid regions 被引量:11
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作者 Irshad AHMAD MENG Xiang-ping +5 位作者 Muhammad KAMRAN Shahzad ALI Shakeel AHMAD LIU Tie-ning CAI Tie HAN Qing-fang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第1期62-77,共16页
Lodging stress results in grain yield and quality reduction in wheat. Uniconazole, a potential plant growth regulator significantly enhances lignin biosynthesis and thus provides mechanical strength to plants in order... Lodging stress results in grain yield and quality reduction in wheat. Uniconazole, a potential plant growth regulator significantly enhances lignin biosynthesis and thus provides mechanical strength to plants in order to cope with lodging stress. A field study was conducted during the 2015–2016 and 2016–2017 growing seasons, to investigate the effects of uniconazole sole application or with micronutrient on the lignin biosynthesis, lodging resistance, and production of winter wheat. In the first experiment, uniconazole at concentrations of 0(CK), 15(US1), 30(US2), and 45(US3) mg L^-1 was applied as sole seed soaking, while in the second experiment with manganese(Mn) at concentration of 0.06 g L^-1 Mn, 0.06 g L^-1 Mn+ 15 mg L^-1 uniconazole(UMS1), 0.06 g L^-1 Mn+30 mg L^-1 uniconazole(UMS2), and 0.06 g L^-1 Mn+45 mg L^-1 uniconazole(UMS3), respectively. Uniconazole sole application or with micronutrient significantly increased the lignin content by improving the lignin-related enzyme activities of phenylalanine ammonia-lyase, cinnamyl alcohol dehydrogenase, tyrosine ammonialyase, and peroxidase, ameliorating basal internode characteristics, and breaking strength. The spike length, spike diameter, spikes/plant, weight/spike, yield/spike, and grain yield increased and then decreased with uniconazole application at a higher concentration, where their maximum values were recorded with UMS2 and US2 treatments. The lignin accumulation was positively correlated with lignin-related enzyme activities and breaking strength while, negatively correlated with lodging rate. Uniconazole significantly improved the lignin biosynthesis, lodging resistance, and grain yield of winter wheat and the treatments which showed the greatest effects were uniconazole seed soaking with micronutrient at a concentration of 30 mg L^-1 and 0.06 g L^-1 , and uniconazole sole seed soaking at a concentration of 30 mg L^-1 . 展开更多
关键词 lignin biosynthesis lodging resistance semi-arid regions MANGANESE UNICONAZOLE WHEAT
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Liver-specific gene expression in mesenchymal stem cells is induced by liver cells 被引量:31
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作者 Claudia Lange Philipp Bassler +4 位作者 Michael V. Lioznov Helge Bruns Dietrich Kluth Axel R. Zander Henning C. Fiegel 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第29期4497-4504,共8页
AIM: The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments reveale... AIM: The origin of putative liver cells from distinct bone marrow stem cells, e.g. hematopoietic stem cells or multipotent adult progenitor cells was found in recent in vitro studies. Cell culture experiments revealed a key role of growth factors for the induction of liver-specific genes in stern cell cultures. We investigated the potential of rat mesenchymal stem cells (MSC) from bone marrow to differentiate into hepatocytic cells in vitro. Furthermore, we assessed the influence of cocultured liver cells on induction of liver-specific gene expression. METHODS: Mesenchymal stem cells were marked with green fluorescent protein (GFP) by retroviral gene transduction. Clonal marked MSC were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with SCF, HGF, EGF, and FGF-4 alone, or in presence of freshly isolated rat liver cells. Cells in cocultures were harvested and GFP+ or GFP- cells were separated using fluorescence activated cell sorting. RT-PCR analysis for the stem cell marker Thyl and the hepatocytic markers CK-18, albumin, CK-19, and AFP was performed in the different cell populations. RESULTS: Under the specified culture conditions, rat MSC cocultured with liver cells expressed albumin-, CK-18, CK-19, and AFP-RNA over 3 weeks, whereas MSC cultured alone did not show liver specific gene expression, CONCLUSION: The results indicate that (1) rat MSC from bone marrow can differentiate towards hepatocytic lineage in vitro, and (2) that the microenvironment plays a decisive role for the induction of hepatic differentiation of rMSC. 展开更多
关键词 Mesenchymal stem cells liver-specific differentiation COCULTURE
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Cloning and Characterization of Genes Coding for Fructan Biosynthesis Enzymes (FBEs) in Triticeae Plants 被引量:8
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作者 GAO Xiang SHE Mao-yun +4 位作者 YIN Gui-xiang YU Yang QIAO Wei-hua DU Li-pu YE Xing-guo 《Agricultural Sciences in China》 CAS CSCD 2010年第3期313-324,共12页
Fructan is not only a carbon source for storage but also plays an important role as anti-stress agents in many plant species. Complex fructans having both β-(2,1)- and β-(2,6)-linked fructosyl units accumulate i... Fructan is not only a carbon source for storage but also plays an important role as anti-stress agents in many plant species. Complex fructans having both β-(2,1)- and β-(2,6)-linked fructosyl units accumulate in Triticeae plants commonly. Three enzymes (sucrose: sucrose 1-fructosyltransferase, 1-SST, EC: 2.4.1.99; sucrose: fructan 6-fructosyltransferase, 6- SFT, EC: 2.4.1.10; and fructan: fructan 1-fructosyltransferase, 1-FFT, EC: 2.4.1.100) were involved in fructan biosynthesis in Triticeae plant species. We successfully isolated these genes from tetraploid wheat (Triticum turgidum, genotype: AABB), common wheat (Triticum aestivum L., genotype: AABBDD) and three wild relatives of common wheat, Triticum urartu Thum. (the origin of the AA genome), Aegilops speltoides (Tausch) Gren. (the putative source of the SS genome) and Aegilops tauschii Coss. (the source of the DD genome). Sequence analysis revealed that all the FBEs (fructan biosynthetic enzymes) had three highly conserved functional motifs except 1-SST (EU981912) from tetraploid wheat species only with conserved DPNG. Low pI (isoelectric point) and potential N-glycosylation sites were predicted, which were crucial for protein compartmentation and post-translational process. Analysis on subcelluar localization signals showed that only 6-SFT had vacuolar-directed signal. Sequences alignment result showed that 1-SST and 1-FFT were more conservative and had closer relationship each other, while 6-SFT was more active during the evolution processing. According to the syntenic relationship between wheat and rice genome, FBEs were predicated to be located on the homeologous group 6 and group 2 chromosomes. Expression profile confirmed that expression of all the three FBEs were drought-stress induced. This study can assist to establish a useful theoretical platform for cold- or drought-tolerant improvement of wheat by modulating FBEs expression. 展开更多
关键词 FRUCTANS fructan biosynthesis enzymes gene structure wheat evolution
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Biosynthesis of poly-3-hydroxybutyrate with a high molecular weight by methanotroph from methane and methanol 被引量:6
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作者 Yingxin Zhang Jiaying Xin +2 位作者 Linlin Chen Hao Song Chungu Xia 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第1期103-109,共7页
Poly-3-hydroxybutyrate (PHB) can be produced by various species of bacteria. Among the possible carbon sources, both methane and methanol could be a suitable substrate for the production of PHB. Methane is cheap and... Poly-3-hydroxybutyrate (PHB) can be produced by various species of bacteria. Among the possible carbon sources, both methane and methanol could be a suitable substrate for the production of PHB. Methane is cheap and plentiful not only as natural gas, but also as biogas. Methanol can also maintain methanotrophic activity in some conditions. The methanotrophic strain Methylosinus trichosporium IMV3011 can accumulate PHB with methane and methanol in a brief nonsterile process. Liquid methanol (0.1%) was added to improve the oxidization of methane. The studies were carried out using shake flasks. Cultivation was performed in two stages: a continuous growth phase and a PHB accumulation phase under the conditions short of essential nutrients (ammonium, nitrate, phosphorus, copper, iron (Ⅲ), magnesium or ethylenediamine tetraacetate (EDTA)) in batch culture. It was found that the most suitable growth time for the cell is 144 h. Then an optimized culture condition for second stage was determined, in which the PHB concentration could be much increased to 0.6 g/L. In order to increase PHB content, citric acid was added as an inhibitor of tricarboxylic acid cycle (TCA). It was found that citric acid is favorable for the PHB accumulation, and the PHB yield was increased to 40% (w/w) from the initial yield of 12% (w/w) after nutrient deficiency cultivation. The PHB produced is of very high quality with molecular weight up to 1.5 × 10^6Da. 展开更多
关键词 poly-3-hydroxybutyrate METHANOTROPHS METHANE METHANOL cultivation biosynthesis high molecular weight
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Biosynthesis of silver nanoparticles by using mangrove plant extract and their potential mosquito larvicidal property 被引量:4
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作者 M Gnanadesigan M Anand +5 位作者 S Ravikumar M Maruthupandy V Vijayakumar S Selvam M Dhineshkumar AK Kumaraguru 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第10期799-803,共5页
Objective:To identify the larvicidal activities of silver nano particles synthesised with Rhizophora mucronata(R.mucronata) leaf extract against the larvae of Aedes aegypti(Ae.aegypti) and Culex quinquefasciatus(... Objective:To identify the larvicidal activities of silver nano particles synthesised with Rhizophora mucronata(R.mucronata) leaf extract against the larvae of Aedes aegypti(Ae.aegypti) and Culex quinquefasciatus(Cx.quinquefasciatus).Methods:In vitro larvicidal activities such as LC<sub>50</sub> and LC<sub>90</sub> were assessed for the Ae.aegypti and Cx.quinquefasciatus larval species.Further, characterisation such as UV,XRD,FTIR and AFM analysis were carried out for the synthesised silver nano particles.Results:The LC<sub>50</sub> value of the synthesised silver nano particle was identified as 0.585 and 0.891 mgg/L for Ae.aegypti and Cx.quinquefasciatus larvae respectively. Further,the LG<sub>90</sub> values are also identified as 2.615 and 6.291 mg/L for Ae.aegypti and Cx. quinquefasciatus species respectively.The synthesised silver nanoparticles have maximum absorption at 420 nm with the average size of 60-95 nm.The XRD data showed 20 intense values with various degrees such as 37.10°,47.66°,63.97°and 70.01°.The FTIR data showed prominent peaks in(3 426.89,2 925.49,2 869.56,2 346.95,1 631.49,1 031.73,669.18 and 455.12) different ranges.Conclusions:The biosynthesis of silver nanoparticles with leaf aqueous extract of R. mucronata provides potential source for the larvicidal activity against mosquito borne diseases. 展开更多
关键词 biosynthesis MANGROVES LARVICIDAL
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Biosynthesis of Flower-Shaped CuO Nanostructures and Their Photocatalytic and Antibacterial Activities 被引量:5
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作者 Hafsa Siddiqui MSQureshi Fozia Zia Haque 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第2期224-234,共11页
Copper oxide nanoflowers(CuO-NFs)have been synthesized through a novel green route using Tulsi leaves-extracted eugenol(4-allyl-2-methoxyphenol)as reducing agent.Characterizations results reveal the growth of crystall... Copper oxide nanoflowers(CuO-NFs)have been synthesized through a novel green route using Tulsi leaves-extracted eugenol(4-allyl-2-methoxyphenol)as reducing agent.Characterizations results reveal the growth of crystalline singlephase CuO-NFs with monoclinic structure.The prepared CuO-NFs can effectively degrade methylene blue with 90%efficiency.They also show strong barrier against E.coli(27±2 mm)at the concentration of 100μg mL−1,while at the concentration of 25μg mL−1 weak barrier has been found against all examined bacterial organisms.The results provide important evidence that CuO-NFs have sustainable performance in methylene blue degradation as well as bacterial organisms. 展开更多
关键词 Copper oxide O.Sanctum EUGENOL biosynthesis PHOTOCATALYSIS ANTIBACTERIAL
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Effect of shade stress on lignin biosynthesis in soybean stems 被引量:4
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作者 LIU Wei-guo REN Meng-lu +6 位作者 LIU Ting DU Yong-li ZHOU Tao LIU Xiao-ming LIU Jiang Sajad Hussain YANG Wen-yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第7期1594-1604,共11页
To clarify how shade stress affects lignin biosynthesis in soybean stem, two varieties, Nandou 12(shade tolerant) and Nan 032-4(shade susceptible) grew under normal light and shade conditions(the photosynthetical... To clarify how shade stress affects lignin biosynthesis in soybean stem, two varieties, Nandou 12(shade tolerant) and Nan 032-4(shade susceptible) grew under normal light and shade conditions(the photosynthetically active radiation and the ratio of red:far-red were lower than normal light condition). Lignin accumulation, transcripts of genes involved in lignin biosynthesis, and intermediates content of lignin biosynthesis were analyzed. Both soybean varieties suffered shade stress had increased plant heights and internode lengths, and reduced stem diameters and lignin accumulation in stems. The expression levels of lignin-related genes were significantly influenced by shade stress, with interactions between the light environment and variety. The gene of 3-hydroxylase(C3H), cinnamoyl-Co A reductase(CCR), caffeoylCoAO-methyltransferase(CCoAOMT), and peroxidase(POD) attributed to lignin biosynthesis under shade stress, and the down-regulation of these genes resulted in lower caffeic, sinapic, and ferulic acid levels, which caused a further decrease in lignin biosynthesis. Under shade stress, the shade tolerant soybean variety(Nandou 12) showed stiffer stems, higher lignin content, and greater gene expression level and higher metabolite contents than shade susceptible one. So these characteristics could be used for screening the shade-tolerant soybean for intercropping. 展开更多
关键词 Glycine max STEM shade stress lignin biosynthesis gene expression phenolic acids
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