3.Cloning and expression analysis of farnesyl pyrophosphate synthase from Aquilaria sinensis.
Xin YANG ; Jian-He WEI ; Juan LIU ; Yan-Hong XU
China Journal of Chinese Materia Medica 2013;38(19):3251-3255
Farnesyl diphosphate synthase (FPS) is one of the key rate-limiting enzymes in the sesquiterpene metabolic pathways. In this study, the open reading frame (ORF) of FPS was cloned by PCR based on the transcript sequence of AsFPS1 from the Aquilaria sinensis transcriptome database and sequenced. Total RNA was extracted from the root, stem and leaves of three-year-old A. sinensis, and from healthy and wounded A. sinensis calli, and then reverse-transcribed into single-stranded cDNA as a template for real-time PCR, to detect the expression specificity of AsFPSI in different tissues and its expression profile in responding to different treatments. The result showed that the full length of AsFPS1 was 1 342 bp with the ORF 1 029 bp, encoding 342 amino acids. Tissue expression analysis indicated that AsFPS1 was mainly expressed in root and stem, and was lower in leaves. Inducible-experiments showed that the genes was induced by mechanical wound as well as chemical liquid induction, and reached the highest expression level at 6 h and 12 h, respectively. The full-length cDNA clone of AsFPSI and its expression patterns analysis will provide a foundation for follow-up study on its biological function and agarwood sesquiterpene biosynthesis mechanism.
DNA, Complementary
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genetics
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Geranyltranstransferase
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genetics
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metabolism
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Real-Time Polymerase Chain Reaction
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Thymelaeaceae
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enzymology
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genetics
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metabolism
4.Cloning,expression and characterization of chalcone isomerase from medicinal plant Chinese sumac (Rhus chinensis).
Xiao-Yue YANG ; Jing WANG ; Chen LI ; Zhu-Mei REN ; Wen-Li MA
China Journal of Chinese Materia Medica 2019;44(15):3253-3260
Flavonoids are a group of secondary metabolites found in plants. They have many pharmacological functions and play an important role in Chinese sumac( Rhus chinensis),which is a well-known traditional Chinese medicinal plant. Chalcone isomerase( CHI,EC 5. 5. 1. 6) is one of the key enzymes in the flavonoids biosynthesis pathway. In this paper,the full-length c DNA sequence encoding the chalcone isomerase from R. chinensis( designated as Rc CHI) was cloned by RT-PCR and rapid-amplification of c DNA Ends( RACE). The Rc CHI c DNA sequence was 1 058 bp and the open reading frame( ORF) was 738 bp. The ORF predicted to encode a 245-amino acid polypeptide. Rc CHI gene contained an intron and two exons. The sequence alignments revealed Rc CHI shared47. 1%-71. 6% identity with the homologues in other plants. Real-time PCR analysis showed that the total flavonoid levels were positively correlated with tissue-specific expressions of Rc CHI mRNA in different tissues. The recombinant protein was successfully expressed in an Escherichia coli strain with the p GEX-6 P-1 vector. In this paper,the CHI gene was cloned and characterized in the family of Anacardiaceae and will help us to obtain better knowledge of the flavonoids biosynthesis of the flavonoid compounds in R. chinensis.
Cloning, Molecular
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DNA, Complementary
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Flavonoids
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biosynthesis
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Intramolecular Lyases
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genetics
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Plants, Medicinal
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enzymology
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genetics
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Rhus
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enzymology
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genetics
5.Modification of pGH cDNA using the first intron and adenovirus-mediated expression in CHO cells.
Xiujin LI ; Fei ZHONG ; Shunzhang QI
Chinese Medical Journal 2003;116(8):1267-1269
OBJECTIVEThis study was conducted to investigate the function of the first intron of porcine growth hormone (pGH) gene in the gene expression.
METHODSPCR method was used to amplify the first intron from pig genomic DNA. The intron was then inserted into pGH cDNA to construct pGH cDNA-intron (pGH cDNA-in). The recombinant adenoviruses containing pGH cDNA and pGH cDNA-in genes under control of CMV promoter were generated by homologous recombination method in HEK 293 cells respectively. The effect of the first intron on gene expression was evaluated by comparing the expression levels of pGH cDNA-in and pGH cDNA mediated by adenovirus vectors in CHO cells.
RESULTSThe expression level of pGH cDNA containing the first intron increased by 117%, which was significantly higher than that of pGH cDNA without the intron (P < 0.001).
CONCLUSIONThe first intron of pGH gene has the function to improve pGH gene expression.
Adenoviridae ; genetics ; Animals ; CHO Cells ; Cricetinae ; DNA Transposable Elements ; DNA, Complementary ; DNA, Recombinant ; Genetic Vectors ; Growth Hormone ; genetics ; Introns ; Swine
6.Cloning the coding cDNA sequence of alpha1, beta2 and gamma2 subunit of GABA-A receptor in American king pigeon.
Guang-dong CHENG ; Ya-li CUI ; Shi-wen XU ; Shu LI
Chinese Journal of Applied Physiology 2008;24(4):453-456
AIMTo clone and analyse the coding cDNA sequence of alpha1, beta2 and gamma2 subunit of GABAA receptor in American king Pigeon.
METHODSWithdrew total RNA from the American king pigeon brain, reverse transcribing general primers to acquire a gene set cDNA. Designing specific primers of three subunit mRNA of the GABAA receptor, by RT-PCR respectively expanded the conservative gene of al subunit, beta2 subunit and gamma2 subunit of GABAA receptor, and carried on clone, plastid identification and the sequence measurese of three genes.
RESULTSThe experiment on sequence measures has succeeded that sequence analysis indicated that lengths of the conservative gene of alpha1 subunit, beta2 subunit and gamma2 subunit of GABAA receptor was respectively 899 bp, 597 bp and 563 bp, homology on reference sequence was respectively 94.99%, 94.64% and 96.28%.
CONCLUSIONHomology is high on the conservative gene of alpha1 subunit, beta2 subunit and gamma2 subunit of GABAA receptor of brain tissue of pigeon and chicken but there is a discriminating characteristic in different kinds of animals.
Animals ; Brain ; metabolism ; Cloning, Molecular ; Columbidae ; DNA, Complementary ; genetics ; RNA, Messenger ; genetics ; Receptors, GABA-A ; classification ; genetics ; Sequence Analysis, DNA
7.Application of SNaPshot Technology in Semen-Specific cSNP Genetic Marker.
Rui-Yang TAO ; Shou-Yu WANG ; Chun-Yan YUAN ; Ruo-Cheng XIA ; Cheng-Tao LI
Journal of Forensic Medicine 2023;39(5):465-470
OBJECTIVES:
To explore the feasibility of genetic marker detection of semen-specific coding region single nucleotide polymorphism (cSNP) based on SNaPshot technology in semen stains and mixed body fluid identification.
METHODS:
Genomic DNA (gDNA) and total RNA were extracted from 16 semen stains and 11 mixtures composed of semen and venous blood, and the total RNA was reverse transcribed into complementary DNA (cDNA). The cSNP genetic markers were screened on the validated semen-specific mRNA coding genes. The cSNP multiplex detection system based on SNaPshot technology was established, and samples were genotyped by capillary electrophoresis (CE).
RESULTS:
A multiplex detection system containing 5 semen-specific cSNPs was successfully established. In 16 semen samples, except the cSNP located in the TGM4 gene showed allele loss in cDNA detection results, the gDNA and cDNA typing results of other cSNPs were highly consistent. When detecting semen-venous blood mixtures, the results of cSNP typing detected were consistent with the genotype of semen donor and were not interfered by the genotype of venous blood donor.
CONCLUSIONS
The method of semen-specific cSNPs detection by SNaPshot technology method can be applied to the genotyping of semen (stains) and provide information for determining the origin of semen in mixed body fluids (stains).
Genetic Markers
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Semen
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Polymorphism, Single Nucleotide
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DNA, Complementary/genetics*
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Body Fluids
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RNA, Messenger/genetics*
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DNA
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Saliva
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Forensic Genetics/methods*
8.Prokaryotic expression of Chinese bovine enterokinase catalytic subunit.
He HUANG ; Yang ZHAO ; Gan YI-RU
Chinese Medical Journal 2004;117(2):286-290
BACKGROUNDTo express in vitro the bovine enterokinase catalytic subunit (EKL) protein, which could be used in the future for the cleavage and purification of fusion proteins.
METHODSBovine enterokinase catalytic subunit cDNA was obtained by RT-PCR from duodenal mucosa of a bovine obtained at wholesale market, and then cloned into a pUCmT cloning vector and sequenced. The desired gene fragment was inserted into a pET39b expression plasmid and the recombinant vector pET39b-EKL was transformed into E. coli BL21 (DE3). Protein expression was induced using IPTG. The recombinant DsbA-EKL was purified with His.Tag affinity chromatography, and it bioactivity was analyzed.
RESULTSCompared with the sequence deposited in GenBank, the sequence of the EKL gene cloned in the present study is correct. It was also confirmed that the nucleotide sequence of expression plasmid pET39b-EKL was correct at the conjunction site between the recombinant DNA 5' terminal multi-cloning site and the recombinant fragment. SDS-PAGE analysis indicated that the target product was about 65 kDa and represented 28% of total cell protein. Purified recombinant protein was obtained by metal chelating chromatography using Ni-IDA resin. After desalting and changing the buffer, the crude kinase was incubated at 21 degrees C overnight and shown to have a high autocatalytic cleavage activity.
CONCLUSIONSThe EKL gene from Chinese bovine has been cloned successfully and expressed. This investigation has layed the foundation for future enterokinase activity research and for further large-scale application of expression products.
Animals ; Catalytic Domain ; genetics ; Cattle ; Cloning, Organism ; DNA, Complementary ; Enteropeptidase ; analysis ; genetics ; Recombinant Proteins
10.Screening for endocrine exophthalmos-associated genes/cDNA fragments.
Jianguo ZHENG ; Ying ZHANG ; Congye SHU ; Rixiang GONG
Journal of Biomedical Engineering 2006;23(2):383-387
This study was conducted to screen the endocrine exophthalmos-associated genes or cDNA fragments and provide a basis for exploring the pathogenesis. The cDNA from the thyroid tissues of patients with hyperthyroidism and endocrine exophthalmos (HT&EE) was used as tester cDNA, and that from the thyroid tissues of patients with HT but free from EE was used as driver cDNA. The subtractive PCR products between tester and driver cDNA were obtained through two cycles of subtraction hybridization and two cycles of PCR by using suppression subtractive hybridization, and then were inserted into pT-Adv, a cloning vector. The ligated DNAs were transformed into E. coli DH5alpha competent cells and incubated for proper blue/white color development. Forty-eight white colonies were randomly picked and their inserts were colony PCR amplified. The PCR product from one of the colonies contained two inserts; the others contained single insert, having a size of 0.2 kb to 2 kb. The inserts of transformants were arrayed on nylon membrane. After cDNA/Rsa I digestion the thyroid tissues of patients with HT, and of patients with HT&EE, were labeled with digoxigenin; the nylon membranes were then hybridized respectively with the two cDNA probes for a high throughput screening for positive clones. The clones which were hybridized with the cDNA probe of HE&EE patients but not hybridized with the probe of the HT patients or showed only faint signal of hybridization, were chosen as positive clones and their inserts were candidates for the endocrine exophthalmos genes or cDNA fragments. About 50% of the clones were confirmed as positive clones. The cDNA fragments in the positive clones were the endocrine exophthalmos-associated genes or cDNA fragments. Endocrine exophthalmos
Cloning, Molecular
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DNA, Complementary
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genetics
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Graves Disease
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genetics
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Humans
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Polymerase Chain Reaction