AIM: To investigate the association of the functional monocyte chemotactic protein-1(MCP-1) promoter polymorphism(A-2518G) with spontaneous bacterial peritonitis(SBP).METHODS: Fifty patients with post-hepatitis C live...AIM: To investigate the association of the functional monocyte chemotactic protein-1(MCP-1) promoter polymorphism(A-2518G) with spontaneous bacterial peritonitis(SBP).METHODS: Fifty patients with post-hepatitis C liver cirrhosis and ascites were categorized into two groups; group Ⅰ included 25 patients with SBP and group Ⅱ included 25 patients free from SBP. In addition, a group of 20 healthy volunteers were included. We assessed the MCP-1 gene polymorphism and gene expression as well as interleukin(IL)-10 levels in both blood and ascitic fluid. RESULTS: A significant MCP-1 gene polymorphism was detected in groups Ⅰ and Ⅱ(P = 0.001 and 0.02 respectively). Group Ⅰ was associated with a significantly higher frequency of AG genotype [control 8(40%) vs SBP 19(76.0%), P < 0.001], and group Ⅱ was associated with a significantly higher frequency of GG genotype when compared to healthy volunteers [control 1(5%) vs cirrhotic 16(64%), P < 0.001]. Accordingly, the frequency of G allele was significantly higher in both groups(Ⅰ and Ⅱ) [control 10(25%) vs SBP 27(54%), P < 0.001 and vs cirrhotic 37(74.0%), P < 0.001, respectively]. The total blood and ascetic fluid levels of IL-10 and MCP-1 gene expression were significantly higher in group Ⅰ than in group Ⅱ. Group Ⅰ showed significant reductions in the levels of MCP-1 gene expression and IL-10 in the whole blood and ascetic fluid after therapy. CONCLUSION: MCP-1 GG genotype and G allele may predispose HCV infected patients to a more progressive disease course, while AG genotype may increase the susceptibility to SBP. Patients carrying these genotypes should be under supervision to prevent or restrict further complications.展开更多
Flower development is one of the most vital pathways in plant development, during which the epigenetic regulation of gene expression is essential. DNA methylation, the most conserved epigenetic modification, participa...Flower development is one of the most vital pathways in plant development, during which the epigenetic regulation of gene expression is essential. DNA methylation, the most conserved epigenetic modification, participates in gene expression regulation and transposable element silencing. Honeysuckle(Lonicera japonica) is an important medicinal plant renowned for its colorful and fragrant flowers. Honeysuckle flowers change color from white to gold as a result of carotenoid accumulation during development. However, the role of DNA methylation in flower color changes is not well understood in L. japonica. Here, we performed whole-genome bisulfite sequencing and transcriptome sequencing during flowering development in honeysuckle. The results showed that a decrease in the levels of genome-wide average DNA methylation during flower development and changes in DNA methylation were associated with the expression of demethylase genes. Moreover, many genes involved in carotenoid biosynthesis and degradation, such as Lj PSY1, LjPDS1, LjLCYE, and LjCCD4, have altered expression levels because of hypomethylation, indicating that DNA methylation plays an important role in flower color changes in honeysuckle. Taken together, our data provide epigenetic insights into flower development and color change in honeysuckles.展开更多
Polyploidization is one of the most crucial pathways in introducing speciation and broadening biodiversity, especially in the Plant Kingdom. Although the majority of studies have focused only on allopolyploid or disom...Polyploidization is one of the most crucial pathways in introducing speciation and broadening biodiversity, especially in the Plant Kingdom. Although the majority of studies have focused only on allopolyploid or disomic polyploids, polysomic polyploid species have occurred frequently in higher plants. Due to the occurrence of the capabilities of more copies of alleles in a locus which can have additive dosage effects and/or allelic interactions, polysomic polyploids can lead to unique gene regulations to silence or adjust the expression level to create variations in organ size, metabolic products, and abiotic stress tolerance and biotic stress resistance, etc. This review aims to comprehensively summarize the contemporary understanding and findings concerning the molecular mechanisms of gene expression as well as gene regulation in natural typed and resynthesized polysomic polyploid plants. The review investigates the molecular level of phenomena in polysomic polyploid plants such as 1) typically enlarging organ size and stabilizing meiosis, 2) increasing phytochemical content and metabolic products, 3) enhancing the ability to adapt with biotic and abiotic stress, and 4) changing in gene regulation to silence or adjust the expression levels involve in sequence elimination, methylation, gene suppression, subfunctionalization, neo-functionalization, and transposon activation.展开更多
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
An Ha-ras oncogene was isolated from a cell line of gastric carcinoma called BGE-823 in order to elucidate genetic control and the influence of DNA sequences. The oncogene was cloned and identified as a single nucleot...An Ha-ras oncogene was isolated from a cell line of gastric carcinoma called BGE-823 in order to elucidate genetic control and the influence of DNA sequences. The oncogene was cloned and identified as a single nucleotide substitution of thymine for guanine in the 12th codon through the sequencing of its first axon. We compared the differences of expression and regulation between the transformed Ha-ras cells and untransformed parent cells. Data indicated that the expression of Ha-ras in the transformed cells was five-fold higher than in the untransformed cells and that the Ha-ras gene in the former was hypersensitive toward DNase I. In addition, a nuclear protein of 35 kilodaltons bound strongly to the 2.5 Kb fragment located upstream of the 6.6 Kb Ha-ras gene and contained a CC rich region. These results suggest that there might be another mechanism of activation for the ras gene besides point mutation.展开更多
Proanthocyanidins and flavanoids, both subfamilies of the polyphenols, are highly concentrated in different fruits and berries as well as in fruit pomace. They have shown to exhibit anti-cancer, anti-microbial, anti-o...Proanthocyanidins and flavanoids, both subfamilies of the polyphenols, are highly concentrated in different fruits and berries as well as in fruit pomace. They have shown to exhibit anti-cancer, anti-microbial, anti-oxidative, and im- mune-modulatory effects in vertebrates. Herein the effect of additional apple pomace or red-grape pomace in conven- tional piglet starter feeds were investigated in 36 young growing piglets. Immunological marker gene expression was quantified by quantitative real-time RT-PCR in white blood cells, and intestinal bacterial flora was investigated from weaning to three weeks post weaning. Polyphenol content in red-grape pomace, gut content and tissues were analyzed with HPLC. Flavan-3-ols (epicatechin and catechin) and proanthocyanidins (B1, B2 and C1) were identified in the gas- tro-intestinal tract content, whereas only traces could be detected in various piglet organs. The blood parameters, he- moglobin and hematocrit, were affected and down-regulated in all groups over testing period. In both pomace treated groups more thrombocytes were present compared to the standard feeding group. It turns out, that the pomace diets had greatest impact on the bacterial content in the colon. Results demonstrate that feeding apple pomace and red- grape pomace tended to increase the number of total colonic bacteria. Steptococci/Enterococci increased in the red- grape pomace. C. perfringens was not detectable at the second time point. The number of lactobacilli increased in both applied diets. The number of Clostridium perfringens decreased with the age of the piglets. Trends of mRNA expression changes were found in white blood cell (WBC) between different feeding regimens, since the expression variability in the groups was very high. Between the different time points there were significant differences within the apple pomace group, where TNF? (p = 0.033), NF?B (p = 0.024) and Caspase 3 (p = 0.019) mRNA expression increased signifi- cantly during treatment. We conclude that both polyphenol rich feedings have the potential to positively influence the intestinal flora, blood parameters, and WBC mRNA gene expression pattern of immunological marker genes.展开更多
A full-length cDNA of proteinase inhibitor gene with completed open reading frame of 116 amino acids was cloned from Ralstonia solanacearum (Rs) resistant potato leaves using the rapid amplification of cDNA ends (R...A full-length cDNA of proteinase inhibitor gene with completed open reading frame of 116 amino acids was cloned from Ralstonia solanacearum (Rs) resistant potato leaves using the rapid amplification of cDNA ends (RACE) method and designated as StPI. BLAST search against NCBI showed that the StPI gene shared 89% identity with potato proteinase inhibitor I precursor in nucleotide and 74% in amino acid. Analysis of semi-quantitative RT-PCR indicated that this gene was induced by Rs as well as up-regulated by jasmonic acid (JA). The StPI gene expression reached the highest level during 6-12 h post Rs-inoculation or JA-treatment, and then leveled off. Moreover, this gene was strongly induced by JA and its mRNA accumulation increased more quickly than that of Rs-inoculation. The StPI gene may play a role in potato resistance against Rs. The induction of StPI by Rs invasion may have a similar signal transduction pathway with JA treatment.展开更多
The effect of cyclin-dependent kinase inhibitors Cip1/Wafl (p21) on regulatory expression of survivin transcription in human hepatocellular carcinoma cell HepG2 was observed and the related mechanisms explored. Doxo...The effect of cyclin-dependent kinase inhibitors Cip1/Wafl (p21) on regulatory expression of survivin transcription in human hepatocellular carcinoma cell HepG2 was observed and the related mechanisms explored. Doxorubicin (DOX) was used to treat HepG2. Eukaryotic vector pEGFP-C2-p21 was transfected into HepG2 by lipofectamine and positive clones were screened out by G418. The mRNA expression of p21 and survivin was detected by real-time fluorescent quantitative polymerase chain reaction (RQ-PCR). Flow cytometry was used to examine the cell cycle, and reverse transcription polymerase chain reaction (RT-PCR) was used to measure the levels of E2F-1 and p300. The results showed that: (1) After treatment with DOX, the expression of p21 was increased, whereas that of survivin was reduced during 24 h of treatment; (2) After transfection of pEGFP-C2-p21 into HepG2, p21 level was significantly enhanced to 2100.11-folds or 980.89-folds in comparison to HepG2 or HepG2-C2 group, and survivin level was markedly down-regulated to 0.54% or 0.59% relative to the control groups; (3) Overexpressed p21 resulted in GI/G0 phase arrest (F=31.59, P〈0.01), meanwhile E2F-1 mRNA and p300 mRNA were reduced as compared with those of controls (FE2F-1=I25.28, P〈0.05; Fp300= 46.01, P〈0.01). It was suggested that p21 could be a potential mediator of survivin suppression at transcription level in HepG2 cell, which might be through the block at G1/G0 phase and down-regulation of transcription factors E2F-1 and p300.展开更多
The gene encoding bone morphogenetic protein-7(BMP7) is expressed in the developing kidney in embryos and also in the mature organ in adults. During kidney development, expression of BMP7 is essential to determine the...The gene encoding bone morphogenetic protein-7(BMP7) is expressed in the developing kidney in embryos and also in the mature organ in adults. During kidney development, expression of BMP7 is essential to determine the final number of nephrons in and proper size of the organ. The secreted BMP7 acts on the nephron progenitor cells to exert its dual functions: To maintain and expand the progenitor population and to provide them with competence to respond to differentiation cues, each relying on distinct signaling pathways. Intriguingly, in the adult organ, BMP7 has been implicated in protection against and regeneration from injury. Exogenous administration of recombinant BMP7 to animal models of kidney diseases has shown promising effects in counteracting inflammation, apoptosis and fibrosis evoked upon injury. Although the expression pattern of BMP7 has been well described, the mechanisms by which it is regulated have remained elusive and the processes by which the secretion sites of BMP7 impinge upon its functions in kidney development and diseases have not yet been assessed. Understanding the regulatory mechanisms will pave the way towards gaining better insight into the roles of BMP7, and to achieving desired control of the gene expression as a therapeutic strategy for kidney diseases.展开更多
Phosphoenolpyruvate carboxylase (PEPC) is widely distributed in plants and bacteria, and catalyzes the carboxylation of phosphoenolpyruvate to form oxaloacetate and inorganic phosphate. To investigate the molecular ...Phosphoenolpyruvate carboxylase (PEPC) is widely distributed in plants and bacteria, and catalyzes the carboxylation of phosphoenolpyruvate to form oxaloacetate and inorganic phosphate. To investigate the molecular mechanisms of the regulation and control of peanut oil, with the degenerated primers and RACE-PCR approach, five PEPC genes were cloned from peanut, and designated as AhPEPC1, AhPEPC2, AhPEPC3, AhPEPC4, and AhPEPC5, respectively. The structure and phylogenetic analysis of PEPC protein indicated that AhPEPC1-4 genes encoded a typical plant-type PEPC-enzyme, and AhPEPC5 a bacterial-type. By real-time quantitative RT-PCR approach the expression pattern of each gene was detected in various tissues of normal and high oil-content peanut varieties. It was found that there was a lower expression level of AhPEPCs genes except for the AhPEPC2 in high-oil peanut than normal-oil peanut line. The results provide some fundamental information for the further investigation of plant PEPC proteins and their role in regulation of oil-content in peanut seeds.展开更多
The purpose of this study was to characterize Ta14 S homoeologs and assess their functions in wheat seed development.The genomic and c DNA sequences of three Ta14 S homoeologous genes encoding 14-3-3 proteins were iso...The purpose of this study was to characterize Ta14 S homoeologs and assess their functions in wheat seed development.The genomic and c DNA sequences of three Ta14 S homoeologous genes encoding 14-3-3 proteins were isolated.Sequence analysis revealed that the three homoeologs consisted of five exons and four introns and were very highly conserved in the coding regions and in exon/intron structure,whereas the c DNA sequences were variable in the 5′ and 3′-UTR.The three genes,designated as Ta14S-2A,Ta14S-2B and Ta14S-2D,were located in homoeologous group 2 chromosomes.The polypeptide chains of the three Ta14 S genes were highly similar.These genes were most homologous to Hv14 A from barley.Real-time quantitative PCR indicated that the three Ta14 S genes were differentially expressed in different organs at different developmental stages and all exhibited greater expression in primary roots of 1-day-old germlings than in other tissues.Comparison of the expression patterns of the three homoeologous genes at different times after pollination also revealed that their expression was developmentally regulated.The transcription of Ta14S-2B was clearly higher during seed germination,whereas expressions of Ta14S-2A and Ta14S-2D were up-regulated at the beginning of seed imbibition(0–12 h),but declined thereafter.The results suggested that the three Ta14 S homoeologous genes have regulatory roles in seed development and germination.展开更多
Background:Human leukocyte antigen(HLA)-DP is much less studied than other HLA class Ⅱ antigens,that is,HLA-DR and HLA-DQ,etc.However,the accumulating data have suggested the important roles of DP-restricted response...Background:Human leukocyte antigen(HLA)-DP is much less studied than other HLA class Ⅱ antigens,that is,HLA-DR and HLA-DQ,etc.However,the accumulating data have suggested the important roles of DP-restricted responses in the context of cancer,allergy,and infectious disease.Lack of animal models expressing these genes as authentic cis-haplotypes blocks our understanding for the role of HLA-DP haplotypes in immunity.Methods:To explore the potential cis-acting control elements involved in the tran-scriptional regulation of the HLA-DPA1/DPB1 gene,we performed the expression analysis using bacterial artificial chromosome(BAC)-based transgenic humanized mice in the C57BL/6 background,which carried the entire HLA-DP401 gene locus.We further developed a mouse model of Staphylococcus aureus pneumonia in HLA-DP401 humanized transgenic mice,and performed the analysis on the expres-sion pattern of HLA-DP401 and immunological responses in the model.Results:In this study,we screened and identified a BAC clone spanning the entire HLA-DP gene locus.DNA from this clone was analyzed for integrity by pulsed-field gel electrophoresis and then microinjected into fertilized mouse oocytes to produce transgenic founder animals.Nine sets of PCR primers for regional markers with an average distance of 15 kb between each primer were used to confirm the integrity of the transgene in the five transgenic lines carrying the HLA-DPA1/DPB1 gene.Transgene copy numbers were determined by real-time PCR analysis.HLA-DP401 gene expression was analyzed at the mRNA and protein level.Although infection with S aureus Newman did not alter the percentage of immune cells in the spleen and thymus from the HLA-DP401-H2-Aβ1 humanized mice.Increased expression of HLA-DP401 was observed in the thymus of the humanized mice infected by S aureus.Conclusions:We generated several BAC transgenic mice,and analyzed the expres-sion of HLA-DPA1/DPB1 in those mice.A model of S aureus-induced pneumonia in the HLA-DP401-H2-Aβ1^(-/-)humanized mice was further developed,and S aureus in-fection upregulated the HLA-DP401 expression in thymus of those humanized mice.These findings demonstrate the potential of those HLA-DPA1/DPB1 transgenic humanized mice for developing animal models of infectious diseases and MHC-associated immunological diseases.展开更多
The availability of a large number of sequenced bacterial genomes allows researchers not only to derive functional and regulation information about specific organisms but also to study the fundamental properties of th...The availability of a large number of sequenced bacterial genomes allows researchers not only to derive functional and regulation information about specific organisms but also to study the fundamental properties of the organization of a genome. Here we address an important and chal- lenging question regarding the global arrangement of operons in a bacterial genome: why operons in a bacterial genome are arranged in the way they are. We have previously studied this question and found that operons of more frequently activated pathways tend to be more clustered together in a genome. Specifically, we have developed a simple sequential distance-based pseudo energy func- tion and found that the arrangement of operons in a bacterial genome tend to minimize the clus- teredness function (C value) in comparison with artificially-generated alternatives, for a variety of bacterial genomes. Here we extend our previous work, and report a number of new observations: (a) operons of the same pathways tend to group into a few clusters rather than one; and (b) the global arrangement of these operon clusters tend to minimize a new "energy" function (C+ value) that reflects the efficiency of the transcriptional activation of the encoded pathways. These obser- vations provide insights into further study of the genomic organization of genes in bacteria.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. 169TBS 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 f gene expression in the gynogenetic fish embryogenesis.展开更多
AIM To investigate SBA2 expression in CRC cell lines snd surgical specimens of CRC and sutologous healthy mucosa.METHODS Reverse transcription-polymerase chain reaction (RT-PCR) was used for relative quantification of...AIM To investigate SBA2 expression in CRC cell lines snd surgical specimens of CRC and sutologous 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 β-actin as an internal control.RESULTS In the exponential range of amplification, fairly good linearity demonstrated identical amplification efficiency for SBA2 and β-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 nonmetastasis 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
AIM To study the effects of hypoxia, hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 (MMP-2) in hepatic stellate cells ( HSC).``METHODS The expressions of MMP-2, tissue inhibitor o...AIM To study the effects of hypoxia, hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 (MMP-2) in hepatic stellate cells ( HSC).``METHODS The expressions of MMP-2, tissue inhibitor of mjatrix metalloproteinese-2 ( TIMP-2 ) and membrane type matrix metalloproteiness-l (MT1-MMP) in cultured rat HSC were detected by immunocytochemistry (ICC) and in situ hybridization (ISH). The contents of MMP-2 and TIMP-2 in culture supernatant were detected with ELISA and the activity of MMP-2 in supematant was revealed by zymography.``RESULTS In the situation of hypoxia for 12 h, the expression of MMP-2 protein wss enhenced (hypoxiagroup positive indexes: 5.7 ± 2.0, n = 10; control: 3.2 ±1 .0. n -- 7; P<0.05). while TIMP-2 protein wss decreased in HSC ( hypoxia group positive indexes: 2.5 ± 0.7, n =10: control: 3.6 ± 1.0, n = 7; P<O.05), and the activity ( total A) of MMP-2 in supematant declined obviously (hypoxia group: 7.334 ± 1.922, n = 9; control: 17.277 ±7.424. n= 11; P<0.01). Compared the varied duration of hypoxia, the changes of expressions including mRNA and protein level as well as activity of MMP-2 were most notable in 6 h group. The highest value (Ahypoxia-Acontrol) ofthe protein and the most intense signal of mRNA were in the period of hypoxia for 6 h, along with the lowest activity of MMP-2. In the situation of hyperoxia for 12 h,the contonts (A450) of MMP-2 and TIMP-2 in supernatant were both higher then those in the control, especially the TIMP-2 (hyperoxia group: 0.0499 _+ 0.0144, n = 16;control: 0.0219 ± 0.0098, n = 14; P<0.01), and so was the activity of MMP-2 (hyperoxia group: 5.252 _+ 0.771,n: 14; control: 4.304 +_ 1 .083, n = 12; P<0.05), and the expression of MT1-MMP was increased.``CONCLUSION HSC Js sensitive to the oxygen, hypoxia enhances the expression of MMP-2 and the effect is more marked at the early stage; hyperoxia mainly raises the activity of MMP-2.展开更多
In the adult mouse brain, the subventricular zone lining the lateral ventricles and the subgranular zone in the dentate gyrus of the hippocampus are two zones that contain neural stem cells(NSCs) with the capacity to ...In the adult mouse brain, the subventricular zone lining the lateral ventricles and the subgranular zone in the dentate gyrus of the hippocampus are two zones that contain neural stem cells(NSCs) with the capacity to give rise to neurons and glia during the entire life of the animal. Spatial and temporal regulation of gene expression in the NSCs populationis established and maintained by the coordinated interaction between transcription factors and epigenetic regulators which control stem cell fate. Epigenetic mechanisms are heritable alterations in genome function that do not involve changes in DNA sequence itself but that modulate gene expression, acting as mediators between the environment and the genome. At the molecular level, those epigenetic mechanisms comprise chemical modifications of DNA such as methylation, hydroxymethylation and histone modifications needed for the maintenance of NSC identity. Genomic imprinting is another normal epigenetic process leading to parentalspecific expression of a gene, known to be implicated in the control of gene dosage in the neurogenic niches. The generation of induced pluripotent stem cells from NSCs by expression of defined transcription factors, provide key insights into fundamental principles of stem cell biology. Epigenetic modifications can also occur during reprogramming of NSCs to pluripotency and a better understanding of this process will help to elucidate the mechanisms required for stem cell maintenance. This review takes advantage of recent studies from the epigenetic field to report knowledge regarding the mechanisms of stemness maintenance of neural stem cells in the neurogenic niches.展开更多
The paper presented an implement method for a dynamic gene expression display software based on the GTK. This method established the dynamic presentation system of gene expression which according to gene expression da...The paper presented an implement method for a dynamic gene expression display software based on the GTK. This method established the dynamic presentation system of gene expression which according to gene expression data from gene chip hybridize at different time, adopted a linearity combination model and Pearson correlation coefficient algorithm. The system described the gene expression changes in graphic form, the gene expression changes with time and the changes in characteristics of the gene expression, also the changes in relations of the gene expression and regulation relationships among genes. The system also provided an integrated platform for analysis on gene chips data, especially for the research on the network ofgene regulation.展开更多
It is observed by in situ stain that LDH (1 5) ...nNAD + can probably enter the nucleopore and can be bound bound specifically with the genes that encode them. During the in vitro expression, the dilution of heart nuc...It is observed by in situ stain that LDH (1 5) ...nNAD + can probably enter the nucleopore and can be bound bound specifically with the genes that encode them. During the in vitro expression, the dilution of heart nuclear DNA fragments could enhance the expression activity of LDH/DNA and the amount of expressed LDH (1 5) is in proportion to the amount of dissociable LDH (1 5) on the LDH/DNA. With the integration of 14C Leu to the proteins, it is also observed that the addition of LDH (1 5) ...nNAD + can suppress the in vitro expression activity of LDH/DNA. AFM observation shows that the regulation sequence at the both ends of active genes may be bound with such active factors as proteins encoded by the genes which probably is the main molecular switch of gene expression and regulation we have been always searching for. Our work shows the prospective application of the combination of AFM and isotope labeling in the research of biological reaction.展开更多
Actin is a ubiquitous protein and plays essential roles on cellular structure maintenance and cellular motility in both muscle and non-muscle tissues.Multiple genes encoding muscle actin have been identified from the ...Actin is a ubiquitous protein and plays essential roles on cellular structure maintenance and cellular motility in both muscle and non-muscle tissues.Multiple genes encoding muscle actin have been identified from the ascidians,including those expressed in the larval tail muscle,the adult body-wall muscle,and adult heart muscle.In this study,a novel striated non-tail muscle actin gene was identified from the RNA-seq data of Ciona savignyi embryos.Phylogenetic analysis,alignment of the N-terminal amino acid sequences and comparation of diagnostic residues provided evidence that it had high similarity with vertebrate cardiac and skeletal muscle actin.In situ hybridization and promoter-driven GFP reporter assay revealed that it was specifically expressed in the primordia of the oral and atrial siphon.We hereby defined it as siphon-specific muscle actin coding gene(Cs-SMA).A 201 bp(−1350 bp to−1150 bp)sequence containing T-box and Six1/2 binding motif within the upstream region of Cs-SMA confined the expression of GFP in the siphons of electroporated embryos.Six1/2 binding motif was experimentally confirmed to play indispensable role in controlling the siphon-specific expression of Cs-SMA.The tissue-specific expression of Cs-SMA in the siphon primordia indicated its potential crucial roles in Ciona embryogenesis and organogenesis.展开更多
文摘AIM: To investigate the association of the functional monocyte chemotactic protein-1(MCP-1) promoter polymorphism(A-2518G) with spontaneous bacterial peritonitis(SBP).METHODS: Fifty patients with post-hepatitis C liver cirrhosis and ascites were categorized into two groups; group Ⅰ included 25 patients with SBP and group Ⅱ included 25 patients free from SBP. In addition, a group of 20 healthy volunteers were included. We assessed the MCP-1 gene polymorphism and gene expression as well as interleukin(IL)-10 levels in both blood and ascitic fluid. RESULTS: A significant MCP-1 gene polymorphism was detected in groups Ⅰ and Ⅱ(P = 0.001 and 0.02 respectively). Group Ⅰ was associated with a significantly higher frequency of AG genotype [control 8(40%) vs SBP 19(76.0%), P < 0.001], and group Ⅱ was associated with a significantly higher frequency of GG genotype when compared to healthy volunteers [control 1(5%) vs cirrhotic 16(64%), P < 0.001]. Accordingly, the frequency of G allele was significantly higher in both groups(Ⅰ and Ⅱ) [control 10(25%) vs SBP 27(54%), P < 0.001 and vs cirrhotic 37(74.0%), P < 0.001, respectively]. The total blood and ascetic fluid levels of IL-10 and MCP-1 gene expression were significantly higher in group Ⅰ than in group Ⅱ. Group Ⅰ showed significant reductions in the levels of MCP-1 gene expression and IL-10 in the whole blood and ascetic fluid after therapy. CONCLUSION: MCP-1 GG genotype and G allele may predispose HCV infected patients to a more progressive disease course, while AG genotype may increase the susceptibility to SBP. Patients carrying these genotypes should be under supervision to prevent or restrict further complications.
基金supported by the National Natural Science Foundation of China (Grant Nos. 32160142, 81873095)。
文摘Flower development is one of the most vital pathways in plant development, during which the epigenetic regulation of gene expression is essential. DNA methylation, the most conserved epigenetic modification, participates in gene expression regulation and transposable element silencing. Honeysuckle(Lonicera japonica) is an important medicinal plant renowned for its colorful and fragrant flowers. Honeysuckle flowers change color from white to gold as a result of carotenoid accumulation during development. However, the role of DNA methylation in flower color changes is not well understood in L. japonica. Here, we performed whole-genome bisulfite sequencing and transcriptome sequencing during flowering development in honeysuckle. The results showed that a decrease in the levels of genome-wide average DNA methylation during flower development and changes in DNA methylation were associated with the expression of demethylase genes. Moreover, many genes involved in carotenoid biosynthesis and degradation, such as Lj PSY1, LjPDS1, LjLCYE, and LjCCD4, have altered expression levels because of hypomethylation, indicating that DNA methylation plays an important role in flower color changes in honeysuckle. Taken together, our data provide epigenetic insights into flower development and color change in honeysuckles.
文摘Polyploidization is one of the most crucial pathways in introducing speciation and broadening biodiversity, especially in the Plant Kingdom. Although the majority of studies have focused only on allopolyploid or disomic polyploids, polysomic polyploid species have occurred frequently in higher plants. Due to the occurrence of the capabilities of more copies of alleles in a locus which can have additive dosage effects and/or allelic interactions, polysomic polyploids can lead to unique gene regulations to silence or adjust the expression level to create variations in organ size, metabolic products, and abiotic stress tolerance and biotic stress resistance, etc. This review aims to comprehensively summarize the contemporary understanding and findings concerning the molecular mechanisms of gene expression as well as gene regulation in natural typed and resynthesized polysomic polyploid plants. The review investigates the molecular level of phenomena in polysomic polyploid plants such as 1) typically enlarging organ size and stabilizing meiosis, 2) increasing phytochemical content and metabolic products, 3) enhancing the ability to adapt with biotic and abiotic stress, and 4) changing in gene regulation to silence or adjust the expression levels involve in sequence elimination, methylation, gene suppression, subfunctionalization, neo-functionalization, and transposon activation.
基金Supported by National Natural Science Foundation of China(U1604110,U1404319,31600992,31801332)Key Project of Science and Technology in Henan Province(182102110442,152102110100,152102110036)+6 种基金Nanhu Scholars Program for Young Scholars of XYNU(2016054)Scientific Research Innovation Project for Postgraduate of XYNU(2018KYJJ47)Major Science and Technology Project in Henan Province(121100110200)Student Research Fund Project of XYNU(2018-DXS-066)National Innovation and Entrepreneurship Training Program for Undergraduates(201810477004)Key Scientific Research Projects of Universities in Henan Province(19A180030)Institute for Conservation and Utilization of Agro-bioresources in Dabie Mountains
文摘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.
文摘An Ha-ras oncogene was isolated from a cell line of gastric carcinoma called BGE-823 in order to elucidate genetic control and the influence of DNA sequences. The oncogene was cloned and identified as a single nucleotide substitution of thymine for guanine in the 12th codon through the sequencing of its first axon. We compared the differences of expression and regulation between the transformed Ha-ras cells and untransformed parent cells. Data indicated that the expression of Ha-ras in the transformed cells was five-fold higher than in the untransformed cells and that the Ha-ras gene in the former was hypersensitive toward DNase I. In addition, a nuclear protein of 35 kilodaltons bound strongly to the 2.5 Kb fragment located upstream of the 6.6 Kb Ha-ras gene and contained a CC rich region. These results suggest that there might be another mechanism of activation for the ras gene besides point mutation.
基金This study was supported by the Bayerisches Staatsmin-isterium für Landwirtschaft und Forsten,L/a-7606.2-494.
文摘Proanthocyanidins and flavanoids, both subfamilies of the polyphenols, are highly concentrated in different fruits and berries as well as in fruit pomace. They have shown to exhibit anti-cancer, anti-microbial, anti-oxidative, and im- mune-modulatory effects in vertebrates. Herein the effect of additional apple pomace or red-grape pomace in conven- tional piglet starter feeds were investigated in 36 young growing piglets. Immunological marker gene expression was quantified by quantitative real-time RT-PCR in white blood cells, and intestinal bacterial flora was investigated from weaning to three weeks post weaning. Polyphenol content in red-grape pomace, gut content and tissues were analyzed with HPLC. Flavan-3-ols (epicatechin and catechin) and proanthocyanidins (B1, B2 and C1) were identified in the gas- tro-intestinal tract content, whereas only traces could be detected in various piglet organs. The blood parameters, he- moglobin and hematocrit, were affected and down-regulated in all groups over testing period. In both pomace treated groups more thrombocytes were present compared to the standard feeding group. It turns out, that the pomace diets had greatest impact on the bacterial content in the colon. Results demonstrate that feeding apple pomace and red- grape pomace tended to increase the number of total colonic bacteria. Steptococci/Enterococci increased in the red- grape pomace. C. perfringens was not detectable at the second time point. The number of lactobacilli increased in both applied diets. The number of Clostridium perfringens decreased with the age of the piglets. Trends of mRNA expression changes were found in white blood cell (WBC) between different feeding regimens, since the expression variability in the groups was very high. Between the different time points there were significant differences within the apple pomace group, where TNF? (p = 0.033), NF?B (p = 0.024) and Caspase 3 (p = 0.019) mRNA expression increased signifi- cantly during treatment. We conclude that both polyphenol rich feedings have the potential to positively influence the intestinal flora, blood parameters, and WBC mRNA gene expression pattern of immunological marker genes.
文摘A full-length cDNA of proteinase inhibitor gene with completed open reading frame of 116 amino acids was cloned from Ralstonia solanacearum (Rs) resistant potato leaves using the rapid amplification of cDNA ends (RACE) method and designated as StPI. BLAST search against NCBI showed that the StPI gene shared 89% identity with potato proteinase inhibitor I precursor in nucleotide and 74% in amino acid. Analysis of semi-quantitative RT-PCR indicated that this gene was induced by Rs as well as up-regulated by jasmonic acid (JA). The StPI gene expression reached the highest level during 6-12 h post Rs-inoculation or JA-treatment, and then leveled off. Moreover, this gene was strongly induced by JA and its mRNA accumulation increased more quickly than that of Rs-inoculation. The StPI gene may play a role in potato resistance against Rs. The induction of StPI by Rs invasion may have a similar signal transduction pathway with JA treatment.
基金a grant from Specialized Research Fund for the Doctoral Program of Higher Educa-tion (No. 20060487045)
文摘The effect of cyclin-dependent kinase inhibitors Cip1/Wafl (p21) on regulatory expression of survivin transcription in human hepatocellular carcinoma cell HepG2 was observed and the related mechanisms explored. Doxorubicin (DOX) was used to treat HepG2. Eukaryotic vector pEGFP-C2-p21 was transfected into HepG2 by lipofectamine and positive clones were screened out by G418. The mRNA expression of p21 and survivin was detected by real-time fluorescent quantitative polymerase chain reaction (RQ-PCR). Flow cytometry was used to examine the cell cycle, and reverse transcription polymerase chain reaction (RT-PCR) was used to measure the levels of E2F-1 and p300. The results showed that: (1) After treatment with DOX, the expression of p21 was increased, whereas that of survivin was reduced during 24 h of treatment; (2) After transfection of pEGFP-C2-p21 into HepG2, p21 level was significantly enhanced to 2100.11-folds or 980.89-folds in comparison to HepG2 or HepG2-C2 group, and survivin level was markedly down-regulated to 0.54% or 0.59% relative to the control groups; (3) Overexpressed p21 resulted in GI/G0 phase arrest (F=31.59, P〈0.01), meanwhile E2F-1 mRNA and p300 mRNA were reduced as compared with those of controls (FE2F-1=I25.28, P〈0.05; Fp300= 46.01, P〈0.01). It was suggested that p21 could be a potential mediator of survivin suppression at transcription level in HepG2 cell, which might be through the block at G1/G0 phase and down-regulation of transcription factors E2F-1 and p300.
基金Supported by Grants-in-Aid for Young Scientists(B)(No.15K18454 to Tsujimura T)Scientific Research(B)(No.15H03001 to Hishikawa K)Scientific Research(C)(Nos.25461208 to Takase O,15K09244 to Yoshikawa M and 26462400 to Idei M)from the Japan Society for the Promotion of Science
文摘The gene encoding bone morphogenetic protein-7(BMP7) is expressed in the developing kidney in embryos and also in the mature organ in adults. During kidney development, expression of BMP7 is essential to determine the final number of nephrons in and proper size of the organ. The secreted BMP7 acts on the nephron progenitor cells to exert its dual functions: To maintain and expand the progenitor population and to provide them with competence to respond to differentiation cues, each relying on distinct signaling pathways. Intriguingly, in the adult organ, BMP7 has been implicated in protection against and regeneration from injury. Exogenous administration of recombinant BMP7 to animal models of kidney diseases has shown promising effects in counteracting inflammation, apoptosis and fibrosis evoked upon injury. Although the expression pattern of BMP7 has been well described, the mechanisms by which it is regulated have remained elusive and the processes by which the secretion sites of BMP7 impinge upon its functions in kidney development and diseases have not yet been assessed. Understanding the regulatory mechanisms will pave the way towards gaining better insight into the roles of BMP7, and to achieving desired control of the gene expression as a therapeutic strategy for kidney diseases.
基金supported by the National High Tech-nology Research and Development Program of China(2006AA10A114)the National Basic Research Program of China (2007CB116212)+1 种基金the Natural Science Fundation of Shangdong Province, China(ZR2009DQ004)the Key Technology Research Project of Qingdao, China (07-1-4-16-nsh)
文摘Phosphoenolpyruvate carboxylase (PEPC) is widely distributed in plants and bacteria, and catalyzes the carboxylation of phosphoenolpyruvate to form oxaloacetate and inorganic phosphate. To investigate the molecular mechanisms of the regulation and control of peanut oil, with the degenerated primers and RACE-PCR approach, five PEPC genes were cloned from peanut, and designated as AhPEPC1, AhPEPC2, AhPEPC3, AhPEPC4, and AhPEPC5, respectively. The structure and phylogenetic analysis of PEPC protein indicated that AhPEPC1-4 genes encoded a typical plant-type PEPC-enzyme, and AhPEPC5 a bacterial-type. By real-time quantitative RT-PCR approach the expression pattern of each gene was detected in various tissues of normal and high oil-content peanut varieties. It was found that there was a lower expression level of AhPEPCs genes except for the AhPEPC2 in high-oil peanut than normal-oil peanut line. The results provide some fundamental information for the further investigation of plant PEPC proteins and their role in regulation of oil-content in peanut seeds.
基金financially supported by the Key Transgenic Breeding Program of the Ministry of Agriculture of China(No.2014ZX0800205B-003)the National Natural Science Foundation of China(No.30771332)
文摘The purpose of this study was to characterize Ta14 S homoeologs and assess their functions in wheat seed development.The genomic and c DNA sequences of three Ta14 S homoeologous genes encoding 14-3-3 proteins were isolated.Sequence analysis revealed that the three homoeologs consisted of five exons and four introns and were very highly conserved in the coding regions and in exon/intron structure,whereas the c DNA sequences were variable in the 5′ and 3′-UTR.The three genes,designated as Ta14S-2A,Ta14S-2B and Ta14S-2D,were located in homoeologous group 2 chromosomes.The polypeptide chains of the three Ta14 S genes were highly similar.These genes were most homologous to Hv14 A from barley.Real-time quantitative PCR indicated that the three Ta14 S genes were differentially expressed in different organs at different developmental stages and all exhibited greater expression in primary roots of 1-day-old germlings than in other tissues.Comparison of the expression patterns of the three homoeologous genes at different times after pollination also revealed that their expression was developmentally regulated.The transcription of Ta14S-2B was clearly higher during seed germination,whereas expressions of Ta14S-2A and Ta14S-2D were up-regulated at the beginning of seed imbibition(0–12 h),but declined thereafter.The results suggested that the three Ta14 S homoeologous genes have regulatory roles in seed development and germination.
基金National Science and Technology Major Project,Grant/Award Number:2017ZX10304402-001-006 and 2017ZX10304402-001-012Shanghai Professional Platform for High-level Biosafety Pathogenic Microorganism Detection,Grant/Award Number:18DZ2293000+1 种基金Scientific Research Projects of Shanghai Science and Technology Commission,Grant/Award Number:19140905300Shanghai Public Health Clinical Center General Program and the Start-on Funding,Grant/Award Number:KY-GW-2017-06,KY-GW-2018-11,KY-GW-2018-04,KY-GW-2019-11 and KY-GW-2019-19。
文摘Background:Human leukocyte antigen(HLA)-DP is much less studied than other HLA class Ⅱ antigens,that is,HLA-DR and HLA-DQ,etc.However,the accumulating data have suggested the important roles of DP-restricted responses in the context of cancer,allergy,and infectious disease.Lack of animal models expressing these genes as authentic cis-haplotypes blocks our understanding for the role of HLA-DP haplotypes in immunity.Methods:To explore the potential cis-acting control elements involved in the tran-scriptional regulation of the HLA-DPA1/DPB1 gene,we performed the expression analysis using bacterial artificial chromosome(BAC)-based transgenic humanized mice in the C57BL/6 background,which carried the entire HLA-DP401 gene locus.We further developed a mouse model of Staphylococcus aureus pneumonia in HLA-DP401 humanized transgenic mice,and performed the analysis on the expres-sion pattern of HLA-DP401 and immunological responses in the model.Results:In this study,we screened and identified a BAC clone spanning the entire HLA-DP gene locus.DNA from this clone was analyzed for integrity by pulsed-field gel electrophoresis and then microinjected into fertilized mouse oocytes to produce transgenic founder animals.Nine sets of PCR primers for regional markers with an average distance of 15 kb between each primer were used to confirm the integrity of the transgene in the five transgenic lines carrying the HLA-DPA1/DPB1 gene.Transgene copy numbers were determined by real-time PCR analysis.HLA-DP401 gene expression was analyzed at the mRNA and protein level.Although infection with S aureus Newman did not alter the percentage of immune cells in the spleen and thymus from the HLA-DP401-H2-Aβ1 humanized mice.Increased expression of HLA-DP401 was observed in the thymus of the humanized mice infected by S aureus.Conclusions:We generated several BAC transgenic mice,and analyzed the expres-sion of HLA-DPA1/DPB1 in those mice.A model of S aureus-induced pneumonia in the HLA-DP401-H2-Aβ1^(-/-)humanized mice was further developed,and S aureus in-fection upregulated the HLA-DP401 expression in thymus of those humanized mice.These findings demonstrate the potential of those HLA-DPA1/DPB1 transgenic humanized mice for developing animal models of infectious diseases and MHC-associated immunological diseases.
基金supported in part by National Science Foundation (Grant No. NSF DEB-0830024 and NSF MCB-0958172)by Grant from the BioEnergy Science Center(BESC) of US Department of Energy through the Office of Biological and Environmental Research
文摘The availability of a large number of sequenced bacterial genomes allows researchers not only to derive functional and regulation information about specific organisms but also to study the fundamental properties of the organization of a genome. Here we address an important and chal- lenging question regarding the global arrangement of operons in a bacterial genome: why operons in a bacterial genome are arranged in the way they are. We have previously studied this question and found that operons of more frequently activated pathways tend to be more clustered together in a genome. Specifically, we have developed a simple sequential distance-based pseudo energy func- tion and found that the arrangement of operons in a bacterial genome tend to minimize the clus- teredness function (C value) in comparison with artificially-generated alternatives, for a variety of bacterial genomes. Here we extend our previous work, and report a number of new observations: (a) operons of the same pathways tend to group into a few clusters rather than one; and (b) the global arrangement of these operon clusters tend to minimize a new "energy" function (C+ value) that reflects the efficiency of the transcriptional activation of the encoded pathways. These obser- vations provide insights into further study of the genomic organization of genes in bacteria.
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. 169TBS 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 f gene expression in the gynogenetic fish embryogenesis.
文摘AIM To investigate SBA2 expression in CRC cell lines snd surgical specimens of CRC and sutologous 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 β-actin as an internal control.RESULTS In the exponential range of amplification, fairly good linearity demonstrated identical amplification efficiency for SBA2 and β-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 nonmetastasis 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Supported by the Scientific Research Fund for Doctorate Education,State Educational Commission,No.9837
文摘AIM To study the effects of hypoxia, hyperoxia on the regulation of expression and activity of matrix metalloproteinase-2 (MMP-2) in hepatic stellate cells ( HSC).``METHODS The expressions of MMP-2, tissue inhibitor of mjatrix metalloproteinese-2 ( TIMP-2 ) and membrane type matrix metalloproteiness-l (MT1-MMP) in cultured rat HSC were detected by immunocytochemistry (ICC) and in situ hybridization (ISH). The contents of MMP-2 and TIMP-2 in culture supernatant were detected with ELISA and the activity of MMP-2 in supematant was revealed by zymography.``RESULTS In the situation of hypoxia for 12 h, the expression of MMP-2 protein wss enhenced (hypoxiagroup positive indexes: 5.7 ± 2.0, n = 10; control: 3.2 ±1 .0. n -- 7; P<0.05). while TIMP-2 protein wss decreased in HSC ( hypoxia group positive indexes: 2.5 ± 0.7, n =10: control: 3.6 ± 1.0, n = 7; P<O.05), and the activity ( total A) of MMP-2 in supematant declined obviously (hypoxia group: 7.334 ± 1.922, n = 9; control: 17.277 ±7.424. n= 11; P<0.01). Compared the varied duration of hypoxia, the changes of expressions including mRNA and protein level as well as activity of MMP-2 were most notable in 6 h group. The highest value (Ahypoxia-Acontrol) ofthe protein and the most intense signal of mRNA were in the period of hypoxia for 6 h, along with the lowest activity of MMP-2. In the situation of hyperoxia for 12 h,the contonts (A450) of MMP-2 and TIMP-2 in supernatant were both higher then those in the control, especially the TIMP-2 (hyperoxia group: 0.0499 _+ 0.0144, n = 16;control: 0.0219 ± 0.0098, n = 14; P<0.01), and so was the activity of MMP-2 (hyperoxia group: 5.252 _+ 0.771,n: 14; control: 4.304 +_ 1 .083, n = 12; P<0.05), and the expression of MT1-MMP was increased.``CONCLUSION HSC Js sensitive to the oxygen, hypoxia enhances the expression of MMP-2 and the effect is more marked at the early stage; hyperoxia mainly raises the activity of MMP-2.
基金Supported by Ministerio de Ciencia e Innovación(SAF Program)to Sacri R Ferrónfunded by a Spanish FPI fellowship+1 种基金Ana Domingo-Muelas by a Spanish FPU fellowship from the Ministerio de Educación y CienciaSacri R Ferrón is a Ramón y Cajal investigator
文摘In the adult mouse brain, the subventricular zone lining the lateral ventricles and the subgranular zone in the dentate gyrus of the hippocampus are two zones that contain neural stem cells(NSCs) with the capacity to give rise to neurons and glia during the entire life of the animal. Spatial and temporal regulation of gene expression in the NSCs populationis established and maintained by the coordinated interaction between transcription factors and epigenetic regulators which control stem cell fate. Epigenetic mechanisms are heritable alterations in genome function that do not involve changes in DNA sequence itself but that modulate gene expression, acting as mediators between the environment and the genome. At the molecular level, those epigenetic mechanisms comprise chemical modifications of DNA such as methylation, hydroxymethylation and histone modifications needed for the maintenance of NSC identity. Genomic imprinting is another normal epigenetic process leading to parentalspecific expression of a gene, known to be implicated in the control of gene dosage in the neurogenic niches. The generation of induced pluripotent stem cells from NSCs by expression of defined transcription factors, provide key insights into fundamental principles of stem cell biology. Epigenetic modifications can also occur during reprogramming of NSCs to pluripotency and a better understanding of this process will help to elucidate the mechanisms required for stem cell maintenance. This review takes advantage of recent studies from the epigenetic field to report knowledge regarding the mechanisms of stemness maintenance of neural stem cells in the neurogenic niches.
文摘The paper presented an implement method for a dynamic gene expression display software based on the GTK. This method established the dynamic presentation system of gene expression which according to gene expression data from gene chip hybridize at different time, adopted a linearity combination model and Pearson correlation coefficient algorithm. The system described the gene expression changes in graphic form, the gene expression changes with time and the changes in characteristics of the gene expression, also the changes in relations of the gene expression and regulation relationships among genes. The system also provided an integrated platform for analysis on gene chips data, especially for the research on the network ofgene regulation.
文摘It is observed by in situ stain that LDH (1 5) ...nNAD + can probably enter the nucleopore and can be bound bound specifically with the genes that encode them. During the in vitro expression, the dilution of heart nuclear DNA fragments could enhance the expression activity of LDH/DNA and the amount of expressed LDH (1 5) is in proportion to the amount of dissociable LDH (1 5) on the LDH/DNA. With the integration of 14C Leu to the proteins, it is also observed that the addition of LDH (1 5) ...nNAD + can suppress the in vitro expression activity of LDH/DNA. AFM observation shows that the regulation sequence at the both ends of active genes may be bound with such active factors as proteins encoded by the genes which probably is the main molecular switch of gene expression and regulation we have been always searching for. Our work shows the prospective application of the combination of AFM and isotope labeling in the research of biological reaction.
基金funded by the National Key Research and Development Program of China(Nos.2019YFE0190900,2018YFD0900705).
文摘Actin is a ubiquitous protein and plays essential roles on cellular structure maintenance and cellular motility in both muscle and non-muscle tissues.Multiple genes encoding muscle actin have been identified from the ascidians,including those expressed in the larval tail muscle,the adult body-wall muscle,and adult heart muscle.In this study,a novel striated non-tail muscle actin gene was identified from the RNA-seq data of Ciona savignyi embryos.Phylogenetic analysis,alignment of the N-terminal amino acid sequences and comparation of diagnostic residues provided evidence that it had high similarity with vertebrate cardiac and skeletal muscle actin.In situ hybridization and promoter-driven GFP reporter assay revealed that it was specifically expressed in the primordia of the oral and atrial siphon.We hereby defined it as siphon-specific muscle actin coding gene(Cs-SMA).A 201 bp(−1350 bp to−1150 bp)sequence containing T-box and Six1/2 binding motif within the upstream region of Cs-SMA confined the expression of GFP in the siphons of electroporated embryos.Six1/2 binding motif was experimentally confirmed to play indispensable role in controlling the siphon-specific expression of Cs-SMA.The tissue-specific expression of Cs-SMA in the siphon primordia indicated its potential crucial roles in Ciona embryogenesis and organogenesis.