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Effect of high temperature on the expressions of genes encoding starch synthesis enzymes in developing rice endosperms 被引量:7
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作者 CAO Zhen-zhen PAN Gang +5 位作者 WANG Fu-biao WEI Ke-su LI Zhao-wei SHI Chun-hai GENG Wei CHENG Fang-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第4期642-659,共18页
High temperature is the major environmental factor affecting grain starch properties of cooking rice cultivars. In this study, two non-waxy indica rice genotypes, cv. 9311 and its mutant with extremely high amylose ph... High temperature is the major environmental factor affecting grain starch properties of cooking rice cultivars. In this study, two non-waxy indica rice genotypes, cv. 9311 and its mutant with extremely high amylose phenotype(9311eha) were used to study the differential expressions of genes in starch synthesis and their responses to high temperature(HT). Significant increase in apparent amylose content and hot-water-soluble starch content in mutant 9311 eha were genetically caused by a substitution from AGTTATA to AGGTATA at the leader intron 5′ splice site in Wx gene. This mutation resulted in different m RNA transcript levels, m RNA splicing efficiencies and protein levels of Wx between the two rice genotypes, which also lead to the genotype-dependent alteration in the temporal pattern of Wx transcription and granule-bound starch synthase(GBSS) activity in response to HT. However, changes in the activities of other starch synthesizing enzymes and their expressions of distinct isoform genes were not significant with the Wx gene mutation, thus only minor difference in the particle size of starch granule, chain-length distribution and gelatinization enthalpy were found between the two genotypes. The temporal-specific expression of multiple isoform genes responsive to different temperature regiments indicated that the reduction of GBSS transcript expression under HT was generally accompanied by the decreased expressions of SSSIIa, SSSIIIa and SBEIIb. Consequently, high temperature-ripened grains in 9311 eha showed high proportion of intermediate and long B chains and somewhat lower level of short A chain compared to the wildtype. The temperature-dependent alteration of amylose content was not only attributed to the reduced expression of GBSS, but also associated with the complimentary effect of SSSIIa and SBEIIb. 展开更多
关键词 rice starch synthesis gene expression amylopectin strucrute high temperature
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Information Expression Oriented toward the Hearing-Impaired Based on Sign Language Video Synthesis 被引量:1
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作者 王茹 王立春 +1 位作者 孔德慧 尹宝才 《China Communications》 SCIE CSCD 2011年第1期139-144,共6页
Among the human users of the Internet of Things,the hearing-impaired is a special group of people for whom normal information expression forms,such as voice and video are unaccessible,and most of them have some diffic... Among the human users of the Internet of Things,the hearing-impaired is a special group of people for whom normal information expression forms,such as voice and video are unaccessible,and most of them have some difficulty in understanding information in text form.The hearing-impaired are accustomed to receiving information expressed in sign language.For this situation,a new information expression form for the Internet of Things oriented toward the hearing-impaired is proposed in this paper,and the new expression is based on sign language video synthesis.Under the sign synthesis frame,three modules are necessary:constructing database,searching for appropriate sign language video units and transition units,and generating interpolated frames.With this method,text information could be transformed into sign language expression for the hearing-impaired. 展开更多
关键词 information express sign language video synthesis Internet of Things sign language anima- tion
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Multimodal Expression—Synthesis of Facial Emotion,Mouth Movement and Voice
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作者 张晶 高文 陈熙霖 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第2期63-71,共9页
This paper presents a multimodal system for synthesis of continuous voice and corresponding images of facial emotions. In the emotion synthesis, a general 2 D face model is established and mapped to a particular face... This paper presents a multimodal system for synthesis of continuous voice and corresponding images of facial emotions. In the emotion synthesis, a general 2 D face model is established and mapped to a particular face by locating some key points of the facial image. The edges of eyes and mouth are approximated by Hough transformation on the proposed models, which has significant advantage over other methods of edge extraction of facial organs, such as deformable templates. A synthesized subsystem of text driven speech and mouth movement is obtained by using the method of emotion synthesis. The parameters for mouth movement are considered as the functions of original mouth shape input to meet the difference of mouth movements among different persons. The method of wave editing is used to synthesize speech, in which Chinese syllables are taken as the basic units to save time. Automatic transformation of mouth shape parameters, automatic synchronism of voice and mouth movement, and realtime synthesis ability are the three major features of this subsystem. The present system can synthesize continuous speech consisting of words in first and second standard Chinese word tables and the corresponding mouth movements. 展开更多
关键词 MULTIMODAL expression EMOTION synthesis MOUTH MOVEMENT synthesis speech synthesis
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Expression Regulation of Starch and Storage Protein Synthesis Related Genes in Rice Grains
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作者 Bo PENG Dongyan KONG +18 位作者 Yu PENG Lulu HE Yue JIANG Jingbo YU Mengshi SUN Qin DAI Yuchen LIU Qingqing XIN Ruihua PANG Yanfang SUN Xiaohua SONG Huilong LI Juan PENG Qiying ZHOU Jintao LI Quanxiu WANG Bin DUAN Shizhi SONG Hongyu YUAN 《Asian Agricultural Research》 2019年第1期47-53,共7页
Starch and the storage proteins are the main nutritious substances in crop grains,and their composition and content in grains play a decisive role in the grain quality of rice and other staple food crops.This review h... Starch and the storage proteins are the main nutritious substances in crop grains,and their composition and content in grains play a decisive role in the grain quality of rice and other staple food crops.This review has mainly summarized the new advances in the expression regulation of starch and storage protein synthesis related genes in rice grains.Moreover,the challenges of the starch and storage protein synthesis substances in rice genetic improvement were also discussed.This review will provide important information for genetic improvement of grain quality in rice and,potentially,other staple cereals. 展开更多
关键词 RICE STARCH Storage PROTEIN synthesis Gene expression REGULATION
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HMM-Based Photo-Realistic Talking Face Synthesis Using Facial Expression Parameter Mapping with Deep Neural Networks
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作者 Kazuki Sato Takashi Nose Akinori Ito 《Journal of Computer and Communications》 2017年第10期50-65,共16页
This paper proposes a technique for synthesizing a pixel-based photo-realistic talking face animation using two-step synthesis with HMMs and DNNs. We introduce facial expression parameters as an intermediate represent... This paper proposes a technique for synthesizing a pixel-based photo-realistic talking face animation using two-step synthesis with HMMs and DNNs. We introduce facial expression parameters as an intermediate representation that has a good correspondence with both of the input contexts and the output pixel data of face images. The sequences of the facial expression parameters are modeled using context-dependent HMMs with static and dynamic features. The mapping from the expression parameters to the target pixel images are trained using DNNs. We examine the required amount of the training data for HMMs and DNNs and compare the performance of the proposed technique with the conventional PCA-based technique through objective and subjective evaluation experiments. 展开更多
关键词 Visual-Speech synthesis TALKING Head Hidden MARKOV Models (HMMs) Deep Neural Networks (DNNs) FACIAL expression Parameter
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SYNTHESIS AND EXPRESSION OF A GENE FOR HUMAN TUMOR NECROSIS FACTOR-ALPHA (TNF-α)
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作者 王平 徐贤秀 +2 位作者 唐伟 王启松 朱德煦 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1992年第2期16-22,共7页
TNF-α was found originally In sera of Bacillus Calmette Guerln infected mice as a macrophage derived factor. It Is cytotoxlc for tumor cell and less or not toxic to normal cells in vitor. The gene for human TNF-α wi... TNF-α was found originally In sera of Bacillus Calmette Guerln infected mice as a macrophage derived factor. It Is cytotoxlc for tumor cell and less or not toxic to normal cells in vitor. The gene for human TNF-α with E. coli-preferred codons has been designed according to the amino acid sequence deduced from the cDNA. The gene with 504 bp was divided into 27 oligonucleotide fragments having 30. to 40 nucleotides each. The solid phase phosphotriester method was used for the synthesis of these oligonucleotides. The 27 fragments were annealed to three segments and then linked by T4 DNA ligase. The entire gene was incorporated into plasmld PDR540 with Tac promoter which was used to transform E. coli 7118. The expressed protein was estimated by SDSPAGE with a molecular weight of 1. 7×104Da. The cytotoxlc activity of the product against L-929 cell was 1. 0×107units/ml culture. 展开更多
关键词 TNF PDR synthesis AND expression OF A GENE FOR HUMAN TUMOR NECROSIS FACTOR-ALPHA CCA
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Transcriptomic and metabolomic analysis provides insights into lignin biosynthesis and accumulation and differences in lodging resistance in hybrid wheat
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作者 Weibing Yang Shengquan Zhang +7 位作者 Qiling Hou Jiangang Gao Hanxia Wang Xianchao Chen Xiangzheng Liao Fengting Zhang Changping Zhao Zhilie Qin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1105-1117,共13页
The use of hybrid wheat is one way to improve the yield in the future.However,greater plant heights increase lodging risk to some extent.In this study,two hybrid combinations with differences in lodging resistance wer... The use of hybrid wheat is one way to improve the yield in the future.However,greater plant heights increase lodging risk to some extent.In this study,two hybrid combinations with differences in lodging resistance were used to analyze the stem-related traits during the filling stage,and to investigate the mechanism of the difference in lodging resistance by analyzing lignin synthesis of the basal second internode(BSI).The stem-related traits such as the breaking strength,stem pole substantial degree(SPSD),and rind penetration strength(RPS),as well as the lignin content of the lodging-resistant combination(LRC),were significantly higher than those of the lodgingsensitive combination(LSC).The phenylpropanoid biosynthesis pathway was significantly and simultaneously enriched according to the transcriptomics and metabolomics analysis at the later filling stage.A total of 35 critical regulatory genes involved in the phenylpropanoid pathway were identified.Moreover,42%of the identified genes were significantly and differentially expressed at the later grain-filling stage between the two combinations,among which more than 80%were strongly up-regulated at that stage in the LRC compared with LSC.On the contrary,the LRC displayed lower contents of lignin intermediate metabolites than the LSC.These results suggested that the key to the lodging resistance formation of LRC is largely the higher lignin synthesis at the later grain-filling stage.Finally,breeding strategies for synergistically improving plant height and lodging resistance of hybrid wheat were put forward by comparing the LRC with the conventional wheat applied in large areas. 展开更多
关键词 gene expression lignin synthesis lodging-resistance hybrid wheat
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Control Emotion Intensity for LSTM-Based Expressive Speech Synthesis
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作者 Xiaolian Zhu Liumeng Xue 《国际计算机前沿大会会议论文集》 2019年第2期654-656,共3页
To improve the performance of human-computer interaction interfaces, emotion is considered to be one of the most important factors. The major objective of expressive speech synthesis is to inject various expressions r... To improve the performance of human-computer interaction interfaces, emotion is considered to be one of the most important factors. The major objective of expressive speech synthesis is to inject various expressions reflecting different emotions to the synthesized speech. To effectively model and control the emotion, emotion intensity is introduced for expressive speech synthesis model to generate speech conveyed the delicate and complicate emotional states. The system was composed of an emotion analysis module with the goal of extracting control emotion intensity vector and a speech synthesis module responsible for mapping text characters to speech waveform. The proposed continuous variable “perception vector” is a data-driven approach of controlling the model to synthesize speech with different emotion intensities. Compared with the system using a one-hot vector to control emotion intensity, this model using perception vector is able to learn the high-level emotion information from low-level acoustic features. In terms of the model controllability and flexibility, both the objective and subjective evaluations demonstrate perception vector outperforms one-hot vector. 展开更多
关键词 EMOTION INTENSITY expressive SPEECH synthesis CONTROLLABLE TEXT-TO-SPEECH NEURAL networks
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Molecular Cloning and Characterization of a Novel Gene Involved in Fatty Acid Synthesis in Brassica napus L. 被引量:1
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作者 XIAO Gang ZHANG Zhen-qian +4 位作者 LIU Rui-yang YIN Chang-fa WU Xian-meng TAN Tai-long GUAN Chun-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第6期962-970,共9页
Based on the sequence of a novel expressed sequence tag (EST), the full-length cDNA of 1 017 nucleotides was cloned from Brassica napus cv. Xiangyou 15 through rapid amplification of cDNA ends (RACE). The gene was... Based on the sequence of a novel expressed sequence tag (EST), the full-length cDNA of 1 017 nucleotides was cloned from Brassica napus cv. Xiangyou 15 through rapid amplification of cDNA ends (RACE). The gene was designated as Bnhol34 (HQ585980), encoding a protein of 338 amino acids. BLAST analysis showed no high degree of sequence identity to any known gene. The calculated molecular weight of the Bnhol34 protein was 36.23 kDa, and the theoretical isoelectric point was 8.74. The Bnhol34 was also cloned from a high oleic acid mutant 854-1 through homologous cloning. There was no difference between the two Bnhol34 genes. Bnhol34 was localized in a tissue-specific manner in B. napus, and its expression level was about eight-fold greater in Xiangyou 15 seeds than in 854-1. The promoter region sequences of Bnhol34 were then isolated from Xiangyou 15 and 854-1, and a 93-bp deletion was found to occur in the Bnhol34 promoter region of 854-1. Three abscisic acid-responsive cis-elements (ABRE) were identified in the promoter region of Xiangyou 15. Real-time PCR analyses revealed that exogenous abscisic acid increased Bnhol34 expression by about four-fold in Xiangyou 15 seeds, yet did not change Bnhol34 expression in 854-1. It appeared that Bnhol34 might be abscisic acid insensitive in 854-1. 展开更多
关键词 Brassca napus L. rapid amplification of cDNA ends high-efficient thermal asymmetric interlaced PCR fatty acid synthesis abscisic acid expression
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Text-Driven Chinese Sign Language Synthesis
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作者 徐琳 高文 晏洁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第3期93-98,共6页
Sign language is visual-gestural language mainly used by healing-impaired people to communicate with each other. Gesture and facial expression ale important grammar parts of sign language. In this paper, a graphics me... Sign language is visual-gestural language mainly used by healing-impaired people to communicate with each other. Gesture and facial expression ale important grammar parts of sign language. In this paper, a graphics method is taken to synthesize Chinese Sign Language, and a practical system is implemented. The input of the system is text. The output of the system is "graphics person" who can gesticulate sign language accompanied by facial expression that corresponds to text entered so as to realize automatic translation from text to sign language. It’s a meaningful exploration to computer multimedia data expression and fusion. It can play an important role in education of healingimpaired people and sign language interpretation. 展开更多
关键词 SIGN LANGUAGE SIGN LANGUAGE synthesis GESTURE synthesis facial expression synthesis text-driven
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Diurnal Changes in the Transcription Profiles of Genes Encoding Starch Synthesis-related Enzymes in Wheat Grains under Field Conditions
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作者 Lina WANG Qiaoxia HAN +2 位作者 Xianghong XIAO Tiancai GUO Guozhang KANG 《Agricultural Science & Technology》 CAS 2017年第4期565-569,574,共6页
[Objective] During the filling stage of plant growth and development, storage starch is diurnally synthesized and accumulated in the grains from cereal crops, but the underlying molecular mechanism is unclear. [Method... [Objective] During the filling stage of plant growth and development, storage starch is diurnally synthesized and accumulated in the grains from cereal crops, but the underlying molecular mechanism is unclear. [Method] In this study, grains from the bread wheat cultivar Zhoumai 18 grown in fields were harvested at 15 d after anthesis, and quantitative real-time reverse transcription polymerase chain reaction(qPCR) was used to measure the transcriptional levels of 26 genes encoding starch synthesis-related enzymes at 2 h intervals throughout a diurnal cycle. [Result] Our findings indicated that storage starch was persistently synthesized in wheat grains throughout a 24 h period. The diurnal patterns of the transcriptional levels of 26 genes in wheat grains were classified into two groups. The 13 genes in Group 1 were temporally and highly expressed in wheat grains,and their encoded proteins could play crucial roles in starch synthesis. The other 13 genes in Group 2 were characterized by low or no transcription in wheat grains throughout a diurnal cycle, suggesting their function in the synthesis or degradation of transitory starches in wheat grains. [Conclusion] These results provide information on the molecular mechanism of storage starch synthesis in higher plants. 展开更多
关键词 Diurnal change Gene expression Starch synthesis Transcriptional level Triticum aestivum L.
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Dithiothreitol and PEG Induced Combined Stress May Affect the Expressions of ABA Aldehyde Oxidase, Sucrose Synthase and Proline Metabolic Genes in Maize Seedlings
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作者 Cansu Altuntas Rabiye Terzi 《Phyton-International Journal of Experimental Botany》 SCIE 2020年第3期487-495,共9页
The endoplasmic reticulum(ER)is an organelle in the cell where proteins are created and folded.Folding is a very elaborate process that is often interrupted by various biotic and abiotic stresses,leading to the format... The endoplasmic reticulum(ER)is an organelle in the cell where proteins are created and folded.Folding is a very elaborate process that is often interrupted by various biotic and abiotic stresses,leading to the formation of unfolded and misfolded proteins called ER stress.Dithiothreitol(DTT)-induced unfolded protein response(UPR)in endoplasmic reticulum(ER)has been recently reported in plants.Also,previous studies demonstrated that treatment with polyethylene glycol(PEG 6000)could stimulate water deficit in crops.However,further researches should be conducted to elucidate the molecular mechanism of ER stress response and the relationship between water deficiency and ER.In this study,we examined the expressions of sucrose synthase(SuS)gene,proline metabolic genes and abscisic aldehyde oxidase(AAO3)gene in maize seedlings that were subjected to DTT and PEG induced combined stresses by using quantitative real-time RT-PCR.Three weeks old detached maize seedlings were treated with or without DTT and PEG 6000 for 12 h.The treatment with DTT increased about 2-fold the expression of gene encoding proline synthesis enzyme,pyrroline-5-carboxylate synthetase(P5CS)but no statistically affected the proline catabolism enzyme,proline dehydrogenase(ProDH)in comparison with un-treated seedlings.PEG treatment was also up-regulated P5CS while it was down-regulated ProDH.The relative expression levels of SuS and AAO3 genes statistically enhanced about 2.5 fold under the DTT-induced ER stress.Likewise,the expression levels of SuS and AAO3 genes were up-regulated in the detached seedlings exposed to PEG-induced water deficit.Conversely,the induced gene expressions were down-regulated under the combined stress,the DTT-induced ER stress and PEG-induced water deficit in comparison with the singular stress responses(DTT or PEG).The results indicated that the expressions of genes,related to the synthesis of some signal osmolyte compounds such as proline and sucrose can be suppressed when ER stress occurred under water deficiency in maize seedlings.The changes in the expressions of genes involved in osmolyte and ABA metabolism can be related to ER stress response as well as variations in water status. 展开更多
关键词 ER stress water deficit SUCROSE PROLINE metabolism ABA synthesis gene expression
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Impact of dietary fat levels and fatty acid composition on milk fat synthesis in sows at peak lactation
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作者 Li Zhe Uffe Krogh +3 位作者 Charlotte Lauridsen Mette Olaf Nielsen Zhengfeng Fang Peter Kappel Theil 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1134-1149,共16页
Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis... Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis,and milk fatty acid(FA)output is sparse in sows.This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows.Forty second-parity sows(Danish Landrace×Yorkshire)were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning(d 28 of lactation):low-fat control diet(3%added animal fat);or 1 of 4 high-fat diets with 8%added fat:coconut oil(CO),fish oil(FO),sunflower oil(SO),or 4%octanoic acid plus 4%FO(OFO).Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.Results Daily intake of FA was lowest in low-fat sows within fat levels(P<0.01)and in OFO and FO sows within highfat diets(P<0.01).Daily milk outputs of fat,FA,energy,and FA-derived carbon reflected to a large extent the intake of those.On average,estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo+mobilized FA/d according to method 3.The low-fat diet increased mammary FAS expression(P<0.05)and de novo fat synthesis(method 1;P=0.13)within fat levels.The OFO diet increased de novo fat synthesis(method 1;P<0.05)and numerically upregulated mammary FAS expression compared to the other high-fat diets.Across diets,a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.Conclusions Sows fed diets with low-fat or octanoic acid,through upregulating FAS expression,increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets,indicating that dietary FA intake,dietary fat level,and body fat mobilization in concert determine de novo fat synthesis,amount and profiles of FA in milk. 展开更多
关键词 Carbon metabolism De novo fat synthesis Dietary fatty acid Fat balance Mammary gene expression Mammary lipogenesis Milk fat production Piglet growth
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Molecular cloning,characterization and expression analysis of three key starch synthesis-related genes from the bulb of a rare lily germplasm,Lilium brownii var.giganteum 被引量:2
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作者 Yun WU Minyi SUN +5 位作者 Shiqi LI Ruihan MIN Cong GAO Qundan LYU Ziming REN Yiping XIA 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2021年第6期476-491,共16页
Starch is the predominant compound in bulb scales,and previous studies have shown that bulblet development is closely associated with starch enrichment.However,how starch synthesis affects bulbification at the molecul... Starch is the predominant compound in bulb scales,and previous studies have shown that bulblet development is closely associated with starch enrichment.However,how starch synthesis affects bulbification at the molecular level is unclear.In this study,we demonstrate that Lilium brownii var.giganteum,a wild lily with a giant bulb in nature,and L.brownii,the native species,have different starch levels and characteristics according to cytological and ultra-structural observations.We cloned the complete sequence of three key gene-encoding enzymes(LbgAGPS,LbgGBSS,and LbgSSⅢ)during starch synthesis by rapid amplification of 5’and 3’complementary DNA(cDNA)ends(RACE)technology.Bioinformatics analysis revealed that the proteins deduced by these genes contain the canonical conserved domains.Constructed phylogenetic trees confirmed the evolutionary relationships with proteins from other species,including monocotyledons and dicotyledons.The transcript levels of various tissues and time course samples obtained during bulblet development uncovered relatively high expression levels in bulblets and gradual increase expression accompanying bulblet growth.Moreover,a set of single nucleotide polymorphisms(SNPs)was discovered in the AGPS genes of four lily genotypes,and a purifying selection fashion was predicted according to the non-synonymous/synonymous(Ka/Ks)values.Taken together,our results suggested that key starch-synthesizing genes might play important roles in bulblet development and lead to distinctive phenotypes in bulblet size. 展开更多
关键词 LILIUM Starch synthesis Bulblet development Single nucleotide polymorphism(SNP) expression pattern
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Synthesis and Expression in Escherichia coli of a Human Neutrophil Activating Protein-1/Interleukin-8 Gene
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作者 金冬雁 徐荣辉 +2 位作者 周圆 王平 侯云德 《Science China Chemistry》 SCIE EI CAS 1993年第10期1224-1232,共9页
The complete gene coding for human neutrophilactivating protein-1/interleukin-8 was synthesized using a semi-chemical semi-enzymatic method. The synthetic gene was then overexpressed in Escherichia coli under the temp... The complete gene coding for human neutrophilactivating protein-1/interleukin-8 was synthesized using a semi-chemical semi-enzymatic method. The synthetic gene was then overexpressed in Escherichia coli under the temperature-regulated control of the P_RP_L tandem promoters. As determined by SDS-PAGE and densitometry, the overexpressed protein comprised up to 18.5% and 10.9% of the total soluble protein in E. coli cells grown in shake flasks and in batch fermentation, respectively. The recombinant NAP-1/IL-8 was then purified to>95% homogeneity by gel filtration and cation exchange chromatography. The purified protein appeared as a single band on the SDS-PAGE gel and possessed potent chemotactic activity in the concentration of <10 ng/ml, as assayed by the agarose plate method. An early skin reactivity was also observed when the pure NAP-1/IL-8 was injected subcutaneously into the rabbits. The N-terminal 36 amino acid sequence of the recombinant NAP1/IL-8 was determined using the Edman method and was shown to be identical to that of the ntive protein. 展开更多
关键词 NEUTROPHIL ACTIVATING protein-1/interleukin-8 DNA synthesis expression of CLONED genes protein sequencing.
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不同波长LEDs光源对苦荞芽菜生长、生物活性物积累及抗氧化活性的影响
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作者 陈丽丽 吕平 +5 位作者 吕少杰 房明志 李斌 胡跃高 薛绪掌 康文艺 《中国农学通报》 2024年第12期45-52,共8页
为探究不同波长LEDs光源对苦荞芽菜生长的影响,本研究以黑暗(D)作对照,采用单色红(R)、蓝(B)、绿(G)光源培养苦荞芽菜,收获后分别测定其形态指标、生物活性物积累量、类黄酮合成关键基因表达量及抗氧化活性指标,结果表明:B处理的苦荞芽... 为探究不同波长LEDs光源对苦荞芽菜生长的影响,本研究以黑暗(D)作对照,采用单色红(R)、蓝(B)、绿(G)光源培养苦荞芽菜,收获后分别测定其形态指标、生物活性物积累量、类黄酮合成关键基因表达量及抗氧化活性指标,结果表明:B处理的苦荞芽菜下胚轴呈深红色,伸长生长受到强烈抑制,花青素、总黄酮及总酚积累量均最高,分别是D的7.18、2.96和2.49倍;R处理的下胚轴呈浅粉色,上述3种生物活性物积累量分别是对照的2.56、1.68和1.40倍;G处理的下胚轴伸长与R相似,外观呈透明白色,生物活性物积累量与对照无显著差异。B和R均强烈诱导类黄酮生物合成通路上关键结构基因表达,显著增加苦荞芽菜下胚轴抗氧化活性。此外,各单色光处理均未显著影响苦荞芽菜可食用部位的鲜重。由此可见,红、蓝LEDs光源可显著影响苦荞芽菜形态生长,并增加其生物活性物积累及抗氧化能力,以蓝光最佳。 展开更多
关键词 红/蓝/绿LEDs光源 苦荞芽菜 生物活性物 抗氧化活性 类黄酮合成基因表达
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溶血素 E基因原核表达载体的构建与蛋白诱导表达
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作者 何学仙 何晓艳 潘晓玥 《宁夏医科大学学报》 2024年第7期663-666,共4页
目的构建大肠杆菌(Escherichia Coli,E.coli)溶血素E(Hemolysin E)基因的重组质粒pCZN1-hlyE,诱导表达目的蛋白。方法通过NCBI数据库检索获取E.coli Hemolysin E基因序列(NC_000913.3),采用基于PAS(PCR-based Accurate Synthesis)的全... 目的构建大肠杆菌(Escherichia Coli,E.coli)溶血素E(Hemolysin E)基因的重组质粒pCZN1-hlyE,诱导表达目的蛋白。方法通过NCBI数据库检索获取E.coli Hemolysin E基因序列(NC_000913.3),采用基于PAS(PCR-based Accurate Synthesis)的全基因合成法,设计全长拼接引物,合成目的基因,并成功构建重组质粒pCZN1-hlyE。将构建好的pCZN1-hlyE重组质粒转入大肠杆菌TOP10菌株中,并用异丙基-β-D-硫代半乳糖苷(IPTG)诱导Hemolysin E基因的表达,生成Hemolysin E毒力蛋白。结果经SDS-PAGE凝胶电泳,Western blot分析鉴定目的蛋白Hemolysin E分子量为28.72 kDa,与Hemolysin E基因核酸序列经DNAMAN软件分析所得蛋白分子量一致。结论被诱导表达的Hemolysin E蛋白存在于菌体裂解液上清中,并纯化制备重组蛋白。 展开更多
关键词 溶血素E 全基因合成 原核表达 蛋白诱导表达
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基于转录组测序的苦瓜皂苷合成相关基因的鉴定和分析
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作者 戚仁洁 宁宇 +4 位作者 刘静 刘之洋 徐海 罗志丹 陈龙正 《中国农业科学》 CAS CSCD 北大核心 2024年第9期1779-1793,共15页
【目的】皂苷是苦瓜果实苦味的主要来源,具有降血糖、抗癌等多种药用价值。鉴定和挖掘参与调控苦瓜皂苷生物合成的代谢通路及基因,为进一步深入解析苦瓜皂苷形成的分子机制提供参考。【方法】以苦瓜高代自交系GK24为试验材料,分别在子房... 【目的】皂苷是苦瓜果实苦味的主要来源,具有降血糖、抗癌等多种药用价值。鉴定和挖掘参与调控苦瓜皂苷生物合成的代谢通路及基因,为进一步深入解析苦瓜皂苷形成的分子机制提供参考。【方法】以苦瓜高代自交系GK24为试验材料,分别在子房期(T1)、幼果期(T2)、商品果期(T3)和完全成熟期(T4)取果实组织,通过香草醛-冰醋酸法测定不同时期的苦瓜皂苷含量,利用转录组测序的方法鉴定差异表达基因。【结果】从T1到T4,苦瓜内源皂苷含量随着果实发育而呈现显著下降的趋势。转录组测序共鉴定到17 504个基因,在T1-vs-T2、T2-vs-T3和T3-vs-T4三组比较中,下调表达基因数量均高于上调表达基因数量。GO富集分析表明含磷复合物代谢过程、驱动蛋白复合体和2-琥珀酰-6-羟基-环己二烯-1-羧酸合成酶活性分别是生物过程、细胞组分及分子功能模块最显著富集的条目。KEGG分析显示全局与概述图谱、碳水化合物代谢和氨基酸代谢是3组比较中共同的最显著富集的代谢通路。根据表达模式可将基因划分为20个模块,其中profile 0中基因的表达量从T1到T4逐渐降低,与苦瓜果实发育过程中皂苷含量变化规律一致。从profile 0中鉴定出与苦瓜皂苷生物合成相关的基因14个,包括萜类骨架生物合成通路上的基因AAT1、HMG1、MVK、PMK、MVD2和FPS1,倍半萜与三萜生物合成途径中的基因SS12、SQE1和CPQ及后修饰酶基因CYP97A3、CYP71AN24、UGT94E5及UGT73C6。实时荧光定量PCR(qRT-PCR)结果与RNA-seq结果一致。【结论】苦瓜果实中皂苷含量随着果实不断成熟而逐渐降低。苦瓜皂苷生物合成首先通过上游的萜类骨架生物合成(ko00900)代谢途径完成萜类皂苷骨架的积累,随后通过倍半萜与三萜生物合成(ko00909)代谢途径以及下游的氧化还原酶、糖基转移酶的修饰最终生成皂苷,本研究通过转录组测序共鉴定到14个与苦瓜皂苷生物合成相关的基因。 展开更多
关键词 苦瓜 转录组 差异表达基因 皂苷 合成调控
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苹果PRE6-like基因的克隆及在花青素合成中的功能分析
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作者 黄娟娟 黄亚萍 +2 位作者 李文芳 毛娟 陈佰鸿 《果树学报》 CAS CSCD 北大核心 2024年第5期812-823,共12页
【目的】通过验证苹果非典型成员多效唑抗性蛋白基因(PRE6-like)的功能,探索其在花青素生物合成中的调控作用。【方法】基于俄矮2号芽变枝条果皮转录组测序结果,筛选获得花青素合成相关调节基因MdPRE6-like,对其进行生物信息学分析,克隆... 【目的】通过验证苹果非典型成员多效唑抗性蛋白基因(PRE6-like)的功能,探索其在花青素生物合成中的调控作用。【方法】基于俄矮2号芽变枝条果皮转录组测序结果,筛选获得花青素合成相关调节基因MdPRE6-like,对其进行生物信息学分析,克隆CDS并构建过表达载体,瞬时表达金冠苹果果实,遗传转化苹果愈伤和拟南芥进行功能验证。【结果】MdPRE6-like cDNA全长279 bp,编码92个氨基酸,相对分子质量10450.75 Da,理论等电点(pI)为6.41,含有HLH结构域,亚细胞定位预测结果为细胞核。组织特异性表达分析表明,MdPRE6-like基因在花、果皮中的表达量显著高于根和叶。瞬时表达金冠苹果表明,MdPRE6-like显著促进了金冠苹果果皮注射部位花青素的积累,并显著提高了花青素合成通路相关结构基因的表达水平。MdPRE6-like基因在苹果愈伤组织和拟南芥过表达表明,转基因苹果愈伤组织和拟南芥叶脉中的花青素含量显著高于野生型,且花青素合成通路结构基因表达水平上调。【结论】MdPRE6-like基因能够正向调控花青素的合成和积累,为后续MdPRE6-like基因参与改良苹果果实品质提供理论参考。 展开更多
关键词 苹果 MdPRE6-like 花青素合成 遗传转化 表达水平
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一锅法全细胞催化合成胞苷三磷酸的研究
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作者 沈来伟 任宇红 《现代化工》 CAS CSCD 北大核心 2024年第4期169-174,共6页
分别在大肠杆菌BL21(DE3)中构建胞苷激酶(CDK)与乙酸激酶(ACK)的共表达及融合表达体系和胞苷酸激酶(CMK)与乙酸激酶(ACK)的融合表达体系,其中融合菌株SUMO-CDK-L2-ACK与CMK-L2-ACK构成的双融合催化体系具有较好的催化活性。搭建了双融... 分别在大肠杆菌BL21(DE3)中构建胞苷激酶(CDK)与乙酸激酶(ACK)的共表达及融合表达体系和胞苷酸激酶(CMK)与乙酸激酶(ACK)的融合表达体系,其中融合菌株SUMO-CDK-L2-ACK与CMK-L2-ACK构成的双融合催化体系具有较好的催化活性。搭建了双融合菌全细胞一锅法催化合成胞苷三磷酸(CTP)反应体系,并对其温度、pH、金属离子、乙酰磷酸投加量及菌粉投加量等进行优化。结果表明,在优化反应体系中,反应75 min时CTP产量达到最高为108 mmol/L,总收率达86.4%,实现了CTP的一锅法高效合成。 展开更多
关键词 胞苷三磷酸 全细胞催化 一锅法合成 共表达 融合表达
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