Objective: To identify a cDNA clone from the subtracted library of human hepatocellular carcinoma (HCC). Methods: Suppression subtractive hybridization was used to isolated a panel of genes that are differentially exp...Objective: To identify a cDNA clone from the subtracted library of human hepatocellular carcinoma (HCC). Methods: Suppression subtractive hybridization was used to isolated a panel of genes that are differentially expressed in hepatocellular carcinoma as compared with cirrhotic liver. T/A cloning method was used to construct a subtracted cDNA library. DNA sequencing analysis and Northern blot analysis were also utilized. Results: The cloned cDNA is 787 nucleotides in length and contains an open reading frame of 230 amino acids, which is a cDNA fragment of reported human fibrinogen, gamma polypeptide (FGG). Northern analysis revealed that this gene was overexpressed in two hepatocellular carcinoma cell lines, SMMC-7721 and HepG2. Conclusion: Sequence identity proved the cDNA clone fragment of as FGG gene. Differential expression of the cDNA fragment in HCC suggested that FGG is related to HCC, indicating a new clue for developing a novel diagnostic and prognostic marker.展开更多
Total RNA was extracted from eyestalks of shrimp Penaeus chinensis . Eyestalk cDNA was obtained from total RNA by reverse transcription. Reverse transcriptase polymerase chain reaction (RT PCR) was initiated using eye...Total RNA was extracted from eyestalks of shrimp Penaeus chinensis . Eyestalk cDNA was obtained from total RNA by reverse transcription. Reverse transcriptase polymerase chain reaction (RT PCR) was initiated using eyestalk cDNA and degenerate primers designed from the amino acid sequence of molt inhibiting hormone from shrimp Penaeus japonicu s. A specific cDNA was obtained and cloned into a T vector for sequencing. The cDNA consisted of 201 base pairs and encoding for a peptide of 67 amino acid residues. The peptide of P. chinensis had the highest identity with molt inhibiting hormones of P. japonicus . The cDNA could be a partial gene of molt inhibiting hormones from P. chinensis . This paper reports for the first time cDNA encoding for neuropeptide of P. chinensis .展开更多
AIM: To clone the cDNA of UGT1A9 from a Chinese human liver and establish the Chinese hamster lung (CHL) cell line expressing human UGT1A9. METHODS: cDNA of UGT1 A9 was transcripted from mRNA by reverse transcriptase-...AIM: To clone the cDNA of UGT1A9 from a Chinese human liver and establish the Chinese hamster lung (CHL) cell line expressing human UGT1A9. METHODS: cDNA of UGT1 A9 was transcripted from mRNA by reverse transcriptase-ploymerase chain reaction, and was cloned into the pGEM-T vector which was amplified in the host bacteric E.Coli DH5(alpha). The inserted fragment, verified by DNA sequencing, was subcloned into the Hind III /Not I site of a mammalian expression vector pREP9 to construct the plasmid termed pREP9-UGT1A9. CHL cells were transfected with the resultant recombinants, pREP9-UGT1A9, and selected by G418 (400 mg x L(-1)) for one month. The surviving clone (CHL-UGT1A9) was harvested as a pool and sub-cultured in medium containing G418 to obtain samples forUGT1A9 assays. The enzyme activity of CHL-UGT1A9 towards propranolol in S9 protein of the cell was determined by HPLC. RESULTS: The sequence of the cDNA segment cloned, which was 1666 bp in length, was identical to that released by Gene Bank (GenBank accession number: AF056188) in coding region. The recombinant constructed, pREP9-UGT1A9, contains the entire coding region, along with 18 bp of the 5' and 55 bp of the 3' untranslated region of theUGT1A9 cDNA, respectively. The cell lines established expressed the protein of UGT1A9, and the enzyme activity towards propranolol in S9 protein was found to be 101+/- 24 pmol x min(-1) x mg(-1) protein (n=3), but was not detectable in parental CHL cells. CONCLUSION: The cDNA of UGT1A9 was successfully cloned from a Chinese human liver and transfected into CHL cells. The CHL-UGT1 A9 cell lines established efficiently expressed the protein ofUGT1A9 for the further enzyme study of drug glucuronidation.展开更多
Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accessio...Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accession number: AJ2771380), was isolated by screening of rice unmature seed cDNA library. Sequence analysis indicates that Rb24 contains a putative amino acid sequence, which is homologous to unique 8 amino acids sequence within Drosophila bicoid homeodomain (50% identity, 75% similarity) and involves a lys-9 in putative helix 3. Northern blot analysis of rice RNA has shown that this sequence is expressed in a tissue-specific manner. The transcript was detected strongly in young panicles, but less in young leaves and roots. This results are further confirmed with paraffin section in situ hybridization. The signal is intensive in rice globular embryo and located at the apical tip of the embryo, then, along with the development of embryo, the signal is getting reduced and transfers into both sides of embryo. The existence of bicoid-related sequence in rice embryo and the similarity of polar distribution of bicoid and Rb24 mRNA in early embryo development may implicates a conserved maternal regulation mechanism of body axis presents in Drosophila and in rice.展开更多
AIM: To reveal the liver regeneration (LR) and its controlas well as the occurrence of liver disease and to study the gene expression profiles of 551 genes after partial hepatectomy (PH) in regenerating rat livers.MET...AIM: To reveal the liver regeneration (LR) and its controlas well as the occurrence of liver disease and to study the gene expression profiles of 551 genes after partial hepatectomy (PH) in regenerating rat livers.METHODS: Five hundred and fifty-one expressed sequence tags screened by suppression subtractive hybridization were made into an in-house cDNA microarray, and the expressive genes and their expressive profiles in regenerating rat livers were analyzed by microarray and bioinformatics. RESULTS: Three hundred of the analyzed 551 genes were up- or downregulated more than twofolds at one or more time points during LR. Most of the genes were up- or downregulated 2-5 folds, but the highest reached 90 folds of the control. One hundred and thirty-nine of themshowed upregulation, 135 displayed downregulation, and up or down expression of 26 genes revealed a dependence on regenerating livers. The genes expressedin 24-h regenerating livers were much more than those in the others. Cluster analysis and generalization analysis showed that there were at least six distinct temporal patterns of gene expression in the regenerating livers, that is, genes were expressed in the immediate early phase, early phase, intermediate phase, early-late phase, late phase, terminal phase. CONCLUSION: In LR, the number of down-regulated genes was almost similar to that of the upregulated genes; the successively altered genes were more than the rapidly transient genes. The temporal patterns of gene expression were similar 2 and 4 h, 12 and 16 h, 48 and 96 h, 72 and 144 h after PH. Microarray combined with suppressive subtractive hybridization can effectively identify the genes related to LR.展开更多
AIM: To investigate SBA2 expression in CRC cell lines and surgical specimens of CRC and autologous healthy mucosa. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used for relative quantification...AIM: To investigate SBA2 expression in CRC cell lines and surgical specimens of CRC and autologous healthy mucosa. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used for relative quantification of SBA2 mRNA levels in 4 human CRC cell lines with different grades of differentiation and 30 clinical samples. Normalization of the results was achieved by simultaneous amplification of beta-actin as an internal control. RESULTS: In the exponential range of amplification, fairly good linearity demonstrated identical amplification efficiency for SBA2 and beta-actin (82%). Markedly lower levels of SBA2 mRNA were detectable in tumors, as compared with the coupled normal counterparts P【0.01). SBA2 expression was significantly (0.01】P 【 0.05) correlated with the grade of differentiation in CRC, with relatively higher levels in well-differentiated samples and lower in poorly-differentiated cases. Of the 9 cases with lymph nodes affected, 78% (7/9) had reduced SBA2 mRNA expression in contrast to 24% (5/21) in non-metastasis samples 0.01】P【0.05). CONCLUSION: SBA2 gene might be a promising novel biomarker of cell differentiation in colorectal cancer and its biological features need further studies.展开更多
A systemic study was initiated to identify stage-specific expression genes in fish embryogenesis by using suppression subtractive hybridization (SSH) technique. In this study, we presented a preliminary result on scre...A systemic study was initiated to identify stage-specific expression genes in fish embryogenesis by using suppression subtractive hybridization (SSH) technique. In this study, we presented a preliminary result on screen for stage-specific expression genes between tail bud stage (TBS) and heartbeat beginning stage (HBS) in gynogenetic silver crucian carp (Carassius auratus gibelio). Two SSH plasmid libraries specific for TBS embryos and HBS embryos were constructed, and stage-specific expression genes were screened between the two stages. 1963 TBS positive clones and 2466 HBS positive clones were sampled to PCR amplification, and 1373 TBS and 1809 HBS PCR positive clones were selected to carry out dot blots. 169 TBS dot blot positive clones and 272 HBS dot blot positive clones were sequenced. Searching GenBank by using these nucleotide sequences indicated that most of the TBS dot blot positive clones could not be found homologous sequences in the database, while known genes were mainly detected from HBS dot blot positive clones. Of the 79 known genes, 20 were enzymes or kinases involved in important metabolism of embryonic development. Moreover, specific expressions of partial genes were further confirmed by virtual northern blots. This study is the first step for making a large attempt to study temporal and spatial control of gene expression in the gynogenetic fish embryogenesis.展开更多
INTRODUCTIONHepatocellular carcinoma(HCC)is one of the major causes of death in the word.The mechanism of carcinogenesis is unknown,although it is widely accepted that HBV and HCV are clsely related to liver cancer[1-...INTRODUCTIONHepatocellular carcinoma(HCC)is one of the major causes of death in the word.The mechanism of carcinogenesis is unknown,although it is widely accepted that HBV and HCV are clsely related to liver cancer[1-5[1-5].Previously,a variety of studies have described the differences in gene expression which distinguished tumor from nontumor[6-11].Cloning of the genes,especially the genes associated with HBV and HCV,is still very important to account for the development of liver cancer.展开更多
The wealth of DNA data generated by the human genome project coupling with recently invented high-throughput gene expression profiling techniques has dramatically sped up the process for biomedical researchers on eluc...The wealth of DNA data generated by the human genome project coupling with recently invented high-throughput gene expression profiling techniques has dramatically sped up the process for biomedical researchers on elucidating the role of genes in human diseases. One powerful method to reveal insight into gene functions is the systematic analysis of gene expression. Two popular high-throughput gene expression technologies, microarray and Serial Analysis of Gene Expression (SAGE) are capable of producing large amounts of gene expression data with the potential of providing novel insights into fundamental disease processes, especially complex syndromes such as cardiovascular disease, whose etiologies are due to multiple genetic factors and their interplay with the environment. Microarray and SAGE have already been used to examine gene expression patterns of cell-culture, animal and human tissues models of cardiovascular diseases. In this review, we will first give a brief introduction of microarray and SAGE technologies and point out their limitations. We will then discuss the major discoveries and the new biological insightsthat have emerged from their applications to cardiovascular diseases. Finally we will touch upon potential challenges and future developments in this area.展开更多
AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing rec...AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF(165) complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or down-regulated. RESULTS: VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR, localized in both the cytoplasm and membrane. Introduction of VEGF(165) antisense into human gastric cancer cells (SGC-7901, immunofluorescence intensity, 31.6%)) resulted in a significant reduction in VEGF-specific messenger RNA and total and cell surface VEGF protein (immunofluorescence intensity, 8.9%) (P【0.05). Conversely, stable integration of VEGF(165) in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity, 75.4%) (P【0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tumor volume: 345.40 +/- 136.31 mm3)(P【0.05 vs control SGC-7901 group: 1534.40 +/- 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tumor volume: 2350.50 +/- 637.70 mm3) (P【0.05 vs control SGC-7901 group). CONCLUSION: This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.展开更多
In searching of differentially expressed genes in human uterine leiomyomas, differential display was used with twelve pairs of primers to compare human uterine leiomyomas with matched myometrium. False positives were ...In searching of differentially expressed genes in human uterine leiomyomas, differential display was used with twelve pairs of primers to compare human uterine leiomyomas with matched myometrium. False positives were eliminated by reverse Northern analysis. Positives were confirmed by Northern blot analysis. RESULTS: Four of 69 cDNA fragments (3 up-regulated named L1, L2 and L3 and 1 down-regulated named M1 in leiomyoma) were confirmed by Northern analysis. Sequence comparison and Northern analysis proved that L1 is exactly the human ribosomal protein S19. It was present ubiquitously in 13 tissues tested but in various levels and even in different size. L1 was highly expressed in parotidean cystadenocarcinoma, pancreatic cancer and breast cancer examined. No mutations have been found in human uterine leiomyomas (n=6). CONCLUSIONS: hRPS19 overexpression might be a universal signal in rapid cell growth tissues.展开更多
AIM: To identify the new alternative splicing variants of human CYP2D6 in human extratumoral liver tissue with RT-PCR and sequencing. METHODS: Full length of human CYP2D6 cDNAs was amplificated by reverse transcriptio...AIM: To identify the new alternative splicing variants of human CYP2D6 in human extratumoral liver tissue with RT-PCR and sequencing. METHODS: Full length of human CYP2D6 cDNAs was amplificated by reverse transcription-polymerase chain reaction (RT-PCR) from a human extratumoral liver tissue and cloned into pGEM-T vector. The cDNA was sequenced. Exons from 1 to 4 of human CYP2D6 cDNAs were also amplificated by RT-PCR from extratumoral liver tissues of 17 human hepatocellular carcinomas. Some RT-PCR products were sequenced. Exons 1 to 4 of CYP2D6 gene were amplified by PCR from extratumoral liver tissue DNA. Two PCR products from extratumoral liver tissues expressing skipped mRNA were partially sequenced. RESULTS: One of the CYP2D6 cDNAs had 470 nucleotides from 79 to 548 (3' portion of exons 1 to 5' portion of exon 4), and was skipped. Exons 1 to 4 of CYP2D6 cDNA were assayed with RT-PCR in 17 extratumoral liver tissues. Both wild type and skipped mRNAs were expressed in 4 samples, only wild type mRNA was expressed in 5 samples, and only skipped mRNA was expressed in 8 samples. Two more variants were identified by sequencing the RT-PCR products of exons 1 to 4 of CYP2D6 cDNA. The second variant skipped 411 nucleotides from 175 to 585. This variant was identified in 4 different liver tissues by sequencing the RT-PCR products. We sequenced partially 2 of the PCR products amplified of CYP2D6 exon 1 to exon 4 from extratumoral liver tissue genomic DNA that only expressed skipped mRNA by RT-PCR. No point mutations around exon 1, intron 1, and exon 4, and no deletion in CYP2D6 gene were detected. The third variant was the skipped exon 3, and 153 bp was lost. CONCLUSION: Three new alternative splicing variants of CYP2D6 mRNA have been identified. They may not be caused by gene mutation and may lose CYP2D6 activity and act as a down-regulator of CYP2D6.展开更多
GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address th...GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address the question, first, 5’ Rapid amplification of cDNA end (RACE) was used to determine GAT1 transcriptional starting sites in neonatal mouse cerebral cortex and intestine, adult mouse brain and adult rat testis. The products of 5’RACE were confirmed by DNA sequencing. We found that the transcript of GAT1 in neonatal mouse cerebral cortex and adult mouse brain starts at the same site (inside of exon 1), while in mouse intestine, GAT1 starts transcription in intron 1, and in rat testis, the transcript of GAT1 has an additional untranslation exon to the 5’ direction.展开更多
We cloned cDNAs for Xenopus aldolases A, B and C. These three aldolase genes are localized on different chromosomes as a single copy gene. In the adult, the aldolase A gene is expressed extensively in muscle tissues, ...We cloned cDNAs for Xenopus aldolases A, B and C. These three aldolase genes are localized on different chromosomes as a single copy gene. In the adult, the aldolase A gene is expressed extensively in muscle tissues, whereas the aldolase B gene is expressed strongly in kidney, liver, stomach and intestine, while the aldolase C gene is expressed in brain, heart and ovary. In oocytes aldolase A and C mRNAs, but not aldolase B mRNA, are extensively transcribed. Thus, aldolase A and C mRNAs, but not B mRNA, occur abundantly in eggs as maternal mRNAs, and strong expression of aldolase B mRNA is seen only after the late neurula stage. We conclude that aldolase A and C mRNAs are major aldolase mRNAs in early stages of Xenopus embryogenesis which proceeds utilizing yolk as the only energy source, aldolase B mRNA, on the other hand, is expressed only later in development in tissues which are required for dietary fructose metabolism.We also isolated the Xenopus aldolase C genomic gene (ca. 12 kb) and found that its promoter (ca. 2 kb)contains regions necessary for tissue-specific expression and also a GC rich region which is essential for basal transcriptional activity.展开更多
IMS To isolate mouse CCR5 cDNA (muCCR5) and study its expression in vivo.METHODS Marathon PCR was used to isolate muCCR5 cDNA and two animal models were designed to investigate the gene expression in vivo, one was m...IMS To isolate mouse CCR5 cDNA (muCCR5) and study its expression in vivo.METHODS Marathon PCR was used to isolate muCCR5 cDNA and two animal models were designed to investigate the gene expression in vivo, one was mouse fulminant hepatitis induced by Propionibacterium acnes (P.acnes) and the other was that with delayed type hypersensitivity reaction (DTH). A specific GSTNH2terminus of muCCR5 fusion protein antibody F(ab′)2 was prepared and clarified. RTPCR and immunohistochemical analysis were used to observe the expression level of CCR5 gene in mice.RESULTS A positive reaction of mouse macrophage was found in DTH but not expressed in P.acnes induced fulminant hepatitis by RTPCR and immunohistochemical analysis.CONCLUSION This muCCR5 expression may be involved in an allergic process mediated by cellular immunity but not acute inflammatory reaction induced by P.acnes..展开更多
OBJECTIVE: To perform cloning of the gene encoding Chinese Schistosoma japonicum tropomyosin (SjcTM) and its expression in Escherichia coli. METHODS: SjcTM cDNA fragment, except for 14 amino acids at the amino terminu...OBJECTIVE: To perform cloning of the gene encoding Chinese Schistosoma japonicum tropomyosin (SjcTM) and its expression in Escherichia coli. METHODS: SjcTM cDNA fragment, except for 14 amino acids at the amino terminus, was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) with total RNA extracted from adult worms of S. japonicum. The RT-PCR product was cloned into T vector and sequenced. The SjcTM cDNA, derived from the constructed TA clone pGEM-SjcTM, was then subcloned into the expressing vector pBV220. After characterization by agarose gel electrophoresis, endonucleases digestion and PCR, the resultant recombinant plasmid was used for expression under the temperature-dependent condition. RESULTS: The RT-PCR product, cloned into a T vector, was sequenced and shown to be 96.5% identical at the nuclei acid level and 98.1% identical in deduced amino acid sequence to that of S. mansoni tropomyosin. The target DNA fragment was then subcloned into a prokaryotic vector pBV220. Induced expression in E. coli DH5alpha cells resulted in a constant level of recombinant protein production. The results of SDS-PAGE and Western blot revealed that the molecular weight of non-fusion recombinant protein (rSjcTM) was approximately 32 kDa and could be recognized specifically by a polyclonal antiserum specific for native S. japonicum tropomyosin (SjcTM). CONCLUSION: The engineering of the cDNA encoding S. japonicum tropomyosin and its bacterial expression was successfully made.展开更多
Fishery is an important industry in China as well as in the rest of the world,and it provides a human food resource containing high-quality protein.Best practice in aquaculture requires a full understanding of the gen...Fishery is an important industry in China as well as in the rest of the world,and it provides a human food resource containing high-quality protein.Best practice in aquaculture requires a full understanding of the genomic controls and transcriptional profiles of cultured fish species.Improvements in aquaculture can be made by regulation of the expression of functional genes.Microarray technology is a powerful tool for rapid screening of genes or transcriptional profiles in a particular fish or for a particular economic character;for example,genes that are related to growth and disease control in the fish.This review provides a brief introduction to microarray technology and its methods and applications,together with a discussion of the achievements in fish biology that have resulted from this technology.展开更多
The mammalian liver has a very strong regeneration capacity after partial hepa- tectomy (PH). To further learn the genes participating in the liver regeneration (LR), 551 cDNAs selected from subtract...The mammalian liver has a very strong regeneration capacity after partial hepa- tectomy (PH). To further learn the genes participating in the liver regeneration (LR), 551 cDNAs selected from subtracted cDNA libraries of the regenerating rat liver were screened by microarray, and their expression pro?les were studied by cluster and generalization analyses. Among them, 177 genes were identi?ed unre- ported and up- or down-regulated more than twofold at one or more time points after PH, of which 62 genes were down-regulated to less than 0.5; 99 genes were up-regulated to 2–10 folds, and 16 genes were either up- or down-regulated at dif- ferent time points during LR. By using BLAST and GENSCAN, these genes were located on responsible chromosomes with 131 genes on the long arms of the chro- mosomes. The cluster and generalization analyses showed that the gene expression pro?les are similar in 2 and 4, 12 and 16, 96 and 144 h respectively after PH, suggesting that the actions of the genes expressed in the same pro?les are similar, and those expressed in di?erent pro?les have less similarity. However, the types, characteristics and functions of the 177 genes remain to be further studied.展开更多
文摘Objective: To identify a cDNA clone from the subtracted library of human hepatocellular carcinoma (HCC). Methods: Suppression subtractive hybridization was used to isolated a panel of genes that are differentially expressed in hepatocellular carcinoma as compared with cirrhotic liver. T/A cloning method was used to construct a subtracted cDNA library. DNA sequencing analysis and Northern blot analysis were also utilized. Results: The cloned cDNA is 787 nucleotides in length and contains an open reading frame of 230 amino acids, which is a cDNA fragment of reported human fibrinogen, gamma polypeptide (FGG). Northern analysis revealed that this gene was overexpressed in two hepatocellular carcinoma cell lines, SMMC-7721 and HepG2. Conclusion: Sequence identity proved the cDNA clone fragment of as FGG gene. Differential expression of the cDNA fragment in HCC suggested that FGG is related to HCC, indicating a new clue for developing a novel diagnostic and prognostic marker.
文摘Total RNA was extracted from eyestalks of shrimp Penaeus chinensis . Eyestalk cDNA was obtained from total RNA by reverse transcription. Reverse transcriptase polymerase chain reaction (RT PCR) was initiated using eyestalk cDNA and degenerate primers designed from the amino acid sequence of molt inhibiting hormone from shrimp Penaeus japonicu s. A specific cDNA was obtained and cloned into a T vector for sequencing. The cDNA consisted of 201 base pairs and encoding for a peptide of 67 amino acid residues. The peptide of P. chinensis had the highest identity with molt inhibiting hormones of P. japonicus . The cDNA could be a partial gene of molt inhibiting hormones from P. chinensis . This paper reports for the first time cDNA encoding for neuropeptide of P. chinensis .
基金Supported by the National Natural Science Foundation of China(C39370805)Zhejiang Provincial Natural Science Foundation(300487)the Excellent Youth Scientist Fund of Zhejiang Province
文摘AIM: To clone the cDNA of UGT1A9 from a Chinese human liver and establish the Chinese hamster lung (CHL) cell line expressing human UGT1A9. METHODS: cDNA of UGT1 A9 was transcripted from mRNA by reverse transcriptase-ploymerase chain reaction, and was cloned into the pGEM-T vector which was amplified in the host bacteric E.Coli DH5(alpha). The inserted fragment, verified by DNA sequencing, was subcloned into the Hind III /Not I site of a mammalian expression vector pREP9 to construct the plasmid termed pREP9-UGT1A9. CHL cells were transfected with the resultant recombinants, pREP9-UGT1A9, and selected by G418 (400 mg x L(-1)) for one month. The surviving clone (CHL-UGT1A9) was harvested as a pool and sub-cultured in medium containing G418 to obtain samples forUGT1A9 assays. The enzyme activity of CHL-UGT1A9 towards propranolol in S9 protein of the cell was determined by HPLC. RESULTS: The sequence of the cDNA segment cloned, which was 1666 bp in length, was identical to that released by Gene Bank (GenBank accession number: AF056188) in coding region. The recombinant constructed, pREP9-UGT1A9, contains the entire coding region, along with 18 bp of the 5' and 55 bp of the 3' untranslated region of theUGT1A9 cDNA, respectively. The cell lines established expressed the protein of UGT1A9, and the enzyme activity towards propranolol in S9 protein was found to be 101+/- 24 pmol x min(-1) x mg(-1) protein (n=3), but was not detectable in parental CHL cells. CONCLUSION: The cDNA of UGT1A9 was successfully cloned from a Chinese human liver and transfected into CHL cells. The CHL-UGT1 A9 cell lines established efficiently expressed the protein ofUGT1A9 for the further enzyme study of drug glucuronidation.
文摘Bicoid is one of the important Drosophila maternal genes involved in the control of embryo polarity and larvae segmentation. To clone and characterize the rice bicoid-related genes, one cDNA clone, Rb24 (EMBL accession number: AJ2771380), was isolated by screening of rice unmature seed cDNA library. Sequence analysis indicates that Rb24 contains a putative amino acid sequence, which is homologous to unique 8 amino acids sequence within Drosophila bicoid homeodomain (50% identity, 75% similarity) and involves a lys-9 in putative helix 3. Northern blot analysis of rice RNA has shown that this sequence is expressed in a tissue-specific manner. The transcript was detected strongly in young panicles, but less in young leaves and roots. This results are further confirmed with paraffin section in situ hybridization. The signal is intensive in rice globular embryo and located at the apical tip of the embryo, then, along with the development of embryo, the signal is getting reduced and transfers into both sides of embryo. The existence of bicoid-related sequence in rice embryo and the similarity of polar distribution of bicoid and Rb24 mRNA in early embryo development may implicates a conserved maternal regulation mechanism of body axis presents in Drosophila and in rice.
基金Supported by the National Natural Science Foundation of China,No. 30270673
文摘AIM: To reveal the liver regeneration (LR) and its controlas well as the occurrence of liver disease and to study the gene expression profiles of 551 genes after partial hepatectomy (PH) in regenerating rat livers.METHODS: Five hundred and fifty-one expressed sequence tags screened by suppression subtractive hybridization were made into an in-house cDNA microarray, and the expressive genes and their expressive profiles in regenerating rat livers were analyzed by microarray and bioinformatics. RESULTS: Three hundred of the analyzed 551 genes were up- or downregulated more than twofolds at one or more time points during LR. Most of the genes were up- or downregulated 2-5 folds, but the highest reached 90 folds of the control. One hundred and thirty-nine of themshowed upregulation, 135 displayed downregulation, and up or down expression of 26 genes revealed a dependence on regenerating livers. The genes expressedin 24-h regenerating livers were much more than those in the others. Cluster analysis and generalization analysis showed that there were at least six distinct temporal patterns of gene expression in the regenerating livers, that is, genes were expressed in the immediate early phase, early phase, intermediate phase, early-late phase, late phase, terminal phase. CONCLUSION: In LR, the number of down-regulated genes was almost similar to that of the upregulated genes; the successively altered genes were more than the rapidly transient genes. The temporal patterns of gene expression were similar 2 and 4 h, 12 and 16 h, 48 and 96 h, 72 and 144 h after PH. Microarray combined with suppressive subtractive hybridization can effectively identify the genes related to LR.
文摘AIM: To investigate SBA2 expression in CRC cell lines and surgical specimens of CRC and autologous healthy mucosa. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used for relative quantification of SBA2 mRNA levels in 4 human CRC cell lines with different grades of differentiation and 30 clinical samples. Normalization of the results was achieved by simultaneous amplification of beta-actin as an internal control. RESULTS: In the exponential range of amplification, fairly good linearity demonstrated identical amplification efficiency for SBA2 and beta-actin (82%). Markedly lower levels of SBA2 mRNA were detectable in tumors, as compared with the coupled normal counterparts P【0.01). SBA2 expression was significantly (0.01】P 【 0.05) correlated with the grade of differentiation in CRC, with relatively higher levels in well-differentiated samples and lower in poorly-differentiated cases. Of the 9 cases with lymph nodes affected, 78% (7/9) had reduced SBA2 mRNA expression in contrast to 24% (5/21) in non-metastasis samples 0.01】P【0.05). CONCLUSION: SBA2 gene might be a promising novel biomarker of cell differentiation in colorectal cancer and its biological features need further studies.
基金This work was supported by the National Nat-ural Science Foundation of China(Grant No.30130240),the Chinese Academy of Sciences(GrantNo.KSCX2-SW-303).
文摘A systemic study was initiated to identify stage-specific expression genes in fish embryogenesis by using suppression subtractive hybridization (SSH) technique. In this study, we presented a preliminary result on screen for stage-specific expression genes between tail bud stage (TBS) and heartbeat beginning stage (HBS) in gynogenetic silver crucian carp (Carassius auratus gibelio). Two SSH plasmid libraries specific for TBS embryos and HBS embryos were constructed, and stage-specific expression genes were screened between the two stages. 1963 TBS positive clones and 2466 HBS positive clones were sampled to PCR amplification, and 1373 TBS and 1809 HBS PCR positive clones were selected to carry out dot blots. 169 TBS dot blot positive clones and 272 HBS dot blot positive clones were sequenced. Searching GenBank by using these nucleotide sequences indicated that most of the TBS dot blot positive clones could not be found homologous sequences in the database, while known genes were mainly detected from HBS dot blot positive clones. Of the 79 known genes, 20 were enzymes or kinases involved in important metabolism of embryonic development. Moreover, specific expressions of partial genes were further confirmed by virtual northern blots. This study is the first step for making a large attempt to study temporal and spatial control of gene expression in the gynogenetic fish embryogenesis.
文摘INTRODUCTIONHepatocellular carcinoma(HCC)is one of the major causes of death in the word.The mechanism of carcinogenesis is unknown,although it is widely accepted that HBV and HCV are clsely related to liver cancer[1-5[1-5].Previously,a variety of studies have described the differences in gene expression which distinguished tumor from nontumor[6-11].Cloning of the genes,especially the genes associated with HBV and HCV,is still very important to account for the development of liver cancer.
基金Part of studies cited in this review was in partsupported by Johns Hopkins Institutional ResearchGrant(Ye,SQ),a pilot project(Ye,SQ)in The Hop-kins DK Center for the Analysis of Gene Expres-sion(R24DK58757-01,NIDDK)and Dorothy WallisWagner Charitable Tru
文摘The wealth of DNA data generated by the human genome project coupling with recently invented high-throughput gene expression profiling techniques has dramatically sped up the process for biomedical researchers on elucidating the role of genes in human diseases. One powerful method to reveal insight into gene functions is the systematic analysis of gene expression. Two popular high-throughput gene expression technologies, microarray and Serial Analysis of Gene Expression (SAGE) are capable of producing large amounts of gene expression data with the potential of providing novel insights into fundamental disease processes, especially complex syndromes such as cardiovascular disease, whose etiologies are due to multiple genetic factors and their interplay with the environment. Microarray and SAGE have already been used to examine gene expression patterns of cell-culture, animal and human tissues models of cardiovascular diseases. In this review, we will first give a brief introduction of microarray and SAGE technologies and point out their limitations. We will then discuss the major discoveries and the new biological insightsthat have emerged from their applications to cardiovascular diseases. Finally we will touch upon potential challenges and future developments in this area.
文摘AIM: To establish the role of vascular endothelial growth factor (VEGF) in the oncogenesis of human gastric carcinoma more directly. METHODS: The expression of VEGF and its receptor kinase-domain insert containing receptor (KDR) in human gastric cancer tissue were observed by immunohistochemical staining. VEGF levels were manipulated in human gastric cancer cell using eukaryotic expression constructs designed to express the complete VEGF(165) complimentary DNA in either the sense or antisense orientation. The biological changes of the cells were observed in which VEGF was up-regulated or down-regulated. RESULTS: VEGF-positive rate was 50%, and VEGF was mainly localized in the cytoplasm and membrane of the tumor cells, while KDR was mainly located in the membrane of vascular endothelial cells in gastric cancer tissues and peri-cancerous tissue. In 2 cases of 50 specimens, the gastric cancer cells expressed KDR, localized in both the cytoplasm and membrane. Introduction of VEGF(165) antisense into human gastric cancer cells (SGC-7901, immunofluorescence intensity, 31.6%)) resulted in a significant reduction in VEGF-specific messenger RNA and total and cell surface VEGF protein (immunofluorescence intensity, 8.9%) (P【0.05). Conversely, stable integration of VEGF(165) in the sense orientation resulted in an increase in cellular and cell surface VEGF (immunofluorescence intensity, 75.4%) (P【0.05). Lowered VEGF levels were associated with a marked decrease in the growth of nude mouse xenografted tumor (at 33 days postimplantation, tumor volume: 345.40 +/- 136.31 mm3)(P【0.05 vs control SGC-7901 group: 1534.40 +/- 362.88 mm3), whereas up-regulation of VEGF resulted in increased xenografted tumor size (at 33 days postimplantation, tumor volume: 2350.50 +/- 637.70 mm3) (P【0.05 vs control SGC-7901 group). CONCLUSION: This study provides direct evidence that VEGF plays an important role in the oncogenesis of human gastric cancer.
文摘In searching of differentially expressed genes in human uterine leiomyomas, differential display was used with twelve pairs of primers to compare human uterine leiomyomas with matched myometrium. False positives were eliminated by reverse Northern analysis. Positives were confirmed by Northern blot analysis. RESULTS: Four of 69 cDNA fragments (3 up-regulated named L1, L2 and L3 and 1 down-regulated named M1 in leiomyoma) were confirmed by Northern analysis. Sequence comparison and Northern analysis proved that L1 is exactly the human ribosomal protein S19. It was present ubiquitously in 13 tissues tested but in various levels and even in different size. L1 was highly expressed in parotidean cystadenocarcinoma, pancreatic cancer and breast cancer examined. No mutations have been found in human uterine leiomyomas (n=6). CONCLUSIONS: hRPS19 overexpression might be a universal signal in rapid cell growth tissues.
基金Supported by the National Key Basic Research and Development Program of China,No.2002CB512901National Natural Science Foundation of China,No.39770868 and Natural Science Foundation of Zhejiang Province,No.397490
文摘AIM: To identify the new alternative splicing variants of human CYP2D6 in human extratumoral liver tissue with RT-PCR and sequencing. METHODS: Full length of human CYP2D6 cDNAs was amplificated by reverse transcription-polymerase chain reaction (RT-PCR) from a human extratumoral liver tissue and cloned into pGEM-T vector. The cDNA was sequenced. Exons from 1 to 4 of human CYP2D6 cDNAs were also amplificated by RT-PCR from extratumoral liver tissues of 17 human hepatocellular carcinomas. Some RT-PCR products were sequenced. Exons 1 to 4 of CYP2D6 gene were amplified by PCR from extratumoral liver tissue DNA. Two PCR products from extratumoral liver tissues expressing skipped mRNA were partially sequenced. RESULTS: One of the CYP2D6 cDNAs had 470 nucleotides from 79 to 548 (3' portion of exons 1 to 5' portion of exon 4), and was skipped. Exons 1 to 4 of CYP2D6 cDNA were assayed with RT-PCR in 17 extratumoral liver tissues. Both wild type and skipped mRNAs were expressed in 4 samples, only wild type mRNA was expressed in 5 samples, and only skipped mRNA was expressed in 8 samples. Two more variants were identified by sequencing the RT-PCR products of exons 1 to 4 of CYP2D6 cDNA. The second variant skipped 411 nucleotides from 175 to 585. This variant was identified in 4 different liver tissues by sequencing the RT-PCR products. We sequenced partially 2 of the PCR products amplified of CYP2D6 exon 1 to exon 4 from extratumoral liver tissue genomic DNA that only expressed skipped mRNA by RT-PCR. No point mutations around exon 1, intron 1, and exon 4, and no deletion in CYP2D6 gene were detected. The third variant was the skipped exon 3, and 153 bp was lost. CONCLUSION: Three new alternative splicing variants of CYP2D6 mRNA have been identified. They may not be caused by gene mutation and may lose CYP2D6 activity and act as a down-regulator of CYP2D6.
基金foundations from Chinese Academy of Sciences and Special Funds for Major State Basic reseaxch of China (G1999053903).
文摘GABA transporter 1(GAT1) takes important roles in multiple physiological processes through the uptake and release of GABA, but the regulation of GAT1 gene expression in different tissues is rarely known. To address the question, first, 5’ Rapid amplification of cDNA end (RACE) was used to determine GAT1 transcriptional starting sites in neonatal mouse cerebral cortex and intestine, adult mouse brain and adult rat testis. The products of 5’RACE were confirmed by DNA sequencing. We found that the transcript of GAT1 in neonatal mouse cerebral cortex and adult mouse brain starts at the same site (inside of exon 1), while in mouse intestine, GAT1 starts transcription in intron 1, and in rat testis, the transcript of GAT1 has an additional untranslation exon to the 5’ direction.
文摘We cloned cDNAs for Xenopus aldolases A, B and C. These three aldolase genes are localized on different chromosomes as a single copy gene. In the adult, the aldolase A gene is expressed extensively in muscle tissues, whereas the aldolase B gene is expressed strongly in kidney, liver, stomach and intestine, while the aldolase C gene is expressed in brain, heart and ovary. In oocytes aldolase A and C mRNAs, but not aldolase B mRNA, are extensively transcribed. Thus, aldolase A and C mRNAs, but not B mRNA, occur abundantly in eggs as maternal mRNAs, and strong expression of aldolase B mRNA is seen only after the late neurula stage. We conclude that aldolase A and C mRNAs are major aldolase mRNAs in early stages of Xenopus embryogenesis which proceeds utilizing yolk as the only energy source, aldolase B mRNA, on the other hand, is expressed only later in development in tissues which are required for dietary fructose metabolism.We also isolated the Xenopus aldolase C genomic gene (ca. 12 kb) and found that its promoter (ca. 2 kb)contains regions necessary for tissue-specific expression and also a GC rich region which is essential for basal transcriptional activity.
文摘IMS To isolate mouse CCR5 cDNA (muCCR5) and study its expression in vivo.METHODS Marathon PCR was used to isolate muCCR5 cDNA and two animal models were designed to investigate the gene expression in vivo, one was mouse fulminant hepatitis induced by Propionibacterium acnes (P.acnes) and the other was that with delayed type hypersensitivity reaction (DTH). A specific GSTNH2terminus of muCCR5 fusion protein antibody F(ab′)2 was prepared and clarified. RTPCR and immunohistochemical analysis were used to observe the expression level of CCR5 gene in mice.RESULTS A positive reaction of mouse macrophage was found in DTH but not expressed in P.acnes induced fulminant hepatitis by RTPCR and immunohistochemical analysis.CONCLUSION This muCCR5 expression may be involved in an allergic process mediated by cellular immunity but not acute inflammatory reaction induced by P.acnes..
文摘OBJECTIVE: To perform cloning of the gene encoding Chinese Schistosoma japonicum tropomyosin (SjcTM) and its expression in Escherichia coli. METHODS: SjcTM cDNA fragment, except for 14 amino acids at the amino terminus, was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) with total RNA extracted from adult worms of S. japonicum. The RT-PCR product was cloned into T vector and sequenced. The SjcTM cDNA, derived from the constructed TA clone pGEM-SjcTM, was then subcloned into the expressing vector pBV220. After characterization by agarose gel electrophoresis, endonucleases digestion and PCR, the resultant recombinant plasmid was used for expression under the temperature-dependent condition. RESULTS: The RT-PCR product, cloned into a T vector, was sequenced and shown to be 96.5% identical at the nuclei acid level and 98.1% identical in deduced amino acid sequence to that of S. mansoni tropomyosin. The target DNA fragment was then subcloned into a prokaryotic vector pBV220. Induced expression in E. coli DH5alpha cells resulted in a constant level of recombinant protein production. The results of SDS-PAGE and Western blot revealed that the molecular weight of non-fusion recombinant protein (rSjcTM) was approximately 32 kDa and could be recognized specifically by a polyclonal antiserum specific for native S. japonicum tropomyosin (SjcTM). CONCLUSION: The engineering of the cDNA encoding S. japonicum tropomyosin and its bacterial expression was successfully made.
基金supported by the Natural Science Foundation of China(Grant Nos.30640015 and 30771644).
文摘Fishery is an important industry in China as well as in the rest of the world,and it provides a human food resource containing high-quality protein.Best practice in aquaculture requires a full understanding of the genomic controls and transcriptional profiles of cultured fish species.Improvements in aquaculture can be made by regulation of the expression of functional genes.Microarray technology is a powerful tool for rapid screening of genes or transcriptional profiles in a particular fish or for a particular economic character;for example,genes that are related to growth and disease control in the fish.This review provides a brief introduction to microarray technology and its methods and applications,together with a discussion of the achievements in fish biology that have resulted from this technology.
基金This work was supported by National Natural Science Foundation of China (No. 30270673).
文摘The mammalian liver has a very strong regeneration capacity after partial hepa- tectomy (PH). To further learn the genes participating in the liver regeneration (LR), 551 cDNAs selected from subtracted cDNA libraries of the regenerating rat liver were screened by microarray, and their expression pro?les were studied by cluster and generalization analyses. Among them, 177 genes were identi?ed unre- ported and up- or down-regulated more than twofold at one or more time points after PH, of which 62 genes were down-regulated to less than 0.5; 99 genes were up-regulated to 2–10 folds, and 16 genes were either up- or down-regulated at dif- ferent time points during LR. By using BLAST and GENSCAN, these genes were located on responsible chromosomes with 131 genes on the long arms of the chro- mosomes. The cluster and generalization analyses showed that the gene expression pro?les are similar in 2 and 4, 12 and 16, 96 and 144 h respectively after PH, suggesting that the actions of the genes expressed in the same pro?les are similar, and those expressed in di?erent pro?les have less similarity. However, the types, characteristics and functions of the 177 genes remain to be further studied.
