Since transgene silencing was found in transgenic plants,many scholars have studied it extensively and considered that it has three functional mechanisms:post dependent gene silencing,transcriptional gene silencing,p...Since transgene silencing was found in transgenic plants,many scholars have studied it extensively and considered that it has three functional mechanisms:post dependent gene silencing,transcriptional gene silencing,post transcriptional gene silencing.At the moment,people have mainly focused on the study of post transcriptional gene silencing and found its features:extensivity,conduction and peculiarity,also put forward some hypothesis for its mechanisms,for example,RNA threshold model,aberrant RNA model,inter or intra molecular base pairing model and so on.Furthermore,post transcriptional gene silencing is being applied in gene engineering of plants.Recently the people have found that post transcriptional gene silencing has bearing on capacity plants resisting virus.Many researchers have studied post transcriptional gene silencing,but there are some questions which need be solved in the future.This article summarizes progresses in features,mechanisms,applies of post transcriptional gene silencing about transgenic plants.展开更多
Isochrysis zhanjiangensis is a dietary microalga renowned for its high content of polyunsaturated fatty acids(PUFAs).However,research on the genes essential for PUFA synthesis in Isochrysis zhanjiangensis is limited.T...Isochrysis zhanjiangensis is a dietary microalga renowned for its high content of polyunsaturated fatty acids(PUFAs).However,research on the genes essential for PUFA synthesis in Isochrysis zhanjiangensis is limited.This study successfully isolated twoΔ9 fatty acid desaturase genes,IZ-delta9-1 and IZ-delta9-2,from Isochrysis zhanjiangensis,which are classified as acyl-lipid desaturases based on phylogenetic analysis.When heterologously expressed in yeast,both genes were confirmed to catalyze the conversion of C16:0 and C18:0 into C16:1 and C18:1,respectively.Furthermore,the impacts of environmental factors on algal growth,fatty acid composition,and transcription levels were explored.Using gas chromatography-mass spectrometry(GC-MS),the fatty acid profiles of I.zhanjiangensis were evaluated.The findings showed that under low temperature(LT)and low nitrogen(LN)conditions,the saturated fatty acids(SFAs)content decreased,and the monounsaturated(MUFAs)and unsaturated fatty acids(UFAs)contents increased.Changes in salinity had a minimal impact on the fatty acid composition.The qPCR analysis revealed that high temperature(HT)and high salt(HS)increased the transcription of IZ-delta9-1,while low nitrogen(LN)and high nitrogen(HN)decreased it.Unlike IZ-delta9-1,the transcription of IZ-delta9-2 significantly increased under both low and high temperature treatments,especially in LT groups.Moreover,compared to the control,the transcription levels of IZ-delta9-1 decreased under improper salinity and nitrogen concentrations.This study is helpful for understanding the fatty acid synthesis pathway in I.zhanjiangensis.展开更多
Based on sequencing of part clones in a root subtractive cDNA library, an expressed sequence tag （EST） sharing high similarity to a rice C2H2 zinc finger transcription factor （ZFP15） was obtained in wheat. Through...Based on sequencing of part clones in a root subtractive cDNA library, an expressed sequence tag （EST） sharing high similarity to a rice C2H2 zinc finger transcription factor （ZFP15） was obtained in wheat. Through bioinformatics approach, the wheat C2H2-type ZFP gene referred to TaZFP15 has been identified and characterized. As a full-length cDNA of 670 bp, TaZFP15 has an open reading frame of 408 bp and encodes a 135-aa polypeptide. TaZFP15 contains two C2H2 zinc finger domains and each one has a conserved motif QALGGH. The typical L-box, generally identified in the C2H2 type transcription factors, has also been found in TaZFP15. Phylogenetic analysis suggested that TaZFP15 shares high similarities with rice ZFP15 （GenBank accession no. AY286473）, maize ZFP （GenBank accession no. NM_001159094） and a subset of other zinc-finger transcription factor genes in plant species. The expression of TaZFP15 was up-regulated by starved-Pi stress, showing a pattern to be gradually elevated along with the progression of the Pi-stress in a 23-h treatment regime. Similarly, the transcripts of TaZFP15 in roots were also induced by nitrogen deficiency, and abiotic stresses of drought and salinity. No responses of TaZFP15 were detected in roots to nutrition deficiencies of P, Zn, and Ca, and the external treatment of abscisic acid （ABA）. TaZFP15 could be specifically amplified in genome A, B, and D, and without variability in the sequences, suggesting that TaZFP15 has multi-copies in the homologous hexaploid species. Transgenic analysis in tobacco revealed that up-regulation of TaZFP15 could significantly improve plant dry mass accumulation via increasing the plant phosphorus acquisition capacity under Pi-deficiency condition. The results suggested that TaZFP15 is involved in mediation of signal transductions of diverse external stresses.展开更多
ICE1, an Arabidopsis thaliana transcription factor gene, was cloned by RT-PCR and successfully transformed into rice variety Kenjiandao 10 by the Agrobacterium-mediated transformation method. PCR amplification and Sou...ICE1, an Arabidopsis thaliana transcription factor gene, was cloned by RT-PCR and successfully transformed into rice variety Kenjiandao 10 by the Agrobacterium-mediated transformation method. PCR amplification and Southern blot analysis indicated that ICE1 had been integrated into rice genome. Compared with the non-transgenic plants, the transgenic plants exhibited high resistance to hygromycin B and were consistent with the Mendelian inheritance of a single copy of the transgenic ICE1. Under the low temperature stress, the transgenic plants showed the lower mortality rate and the increased proline content. These results suggest that the Arabidopsis ICE1 is functional in rice and the over-expression of ICE1 improves the tolerance to cold stress in rice.展开更多
Objective: To study the molecular mechanisms of TNF--a expression induced by lipopolysaccharide (LPS) for exploring novel methods to prevent or treat clinical patients with endotoxic shock. Methods:Protein kinase assa...Objective: To study the molecular mechanisms of TNF--a expression induced by lipopolysaccharide (LPS) for exploring novel methods to prevent or treat clinical patients with endotoxic shock. Methods:Protein kinase assay was used to detect the kinase activity stimulated by LPS; Con focal laser scan technique was used to show the translocation of p38 on the activation; RT PCR and reporter gene system were used to study the molecular mechanism of TNF -a gene transcription. Results: In RAW cells it was found that p38 was activated on the stimulation of LPS. and activated p38 moved into nucleus from cytosol; TNF--a mRNA increased on the stimulation of LPS and the increased promoter transactivity induced by LPS could be inhibited significantly by specific inhibitor for p38. Conclusion: p38 mitogen activated protein kinase (MAPK ) was activated by the stimulation of LPS,which brought about its entry to the nucleus to act on transcription factors to regulate cellular processes. p38 MAPK Is an important regulator of TNF--a gene expression induced by LPS.展开更多
The epithelial Na^＋ channel （ENaC） consists of α, β, γ subunits. Its expression and function are regulated by aldosterone at multiple levels including transcription. ENaC plays a key role in Na^＋ homeostasis a...The epithelial Na^＋ channel （ENaC） consists of α, β, γ subunits. Its expression and function are regulated by aldosterone at multiple levels including transcription. ENaC plays a key role in Na^＋ homeostasis and blood pressure. Mutations in ENaC subunit genes result in hypertension or hypotension, depending on the nature of the mutations. Transcription of αENaC is considered as the rate-limiting step in the formation of functional ENaC. As an aldosterone target gene, αENaC is activated upon aldosterone- mineralocorticoid receptor binding to the cis-elements in the αENaC promoter, which is packed into chromatin. However, how aldosterone alters chromatin structure to induce changes in transcription is poorly understood. Studies by others and us suggest that Dot1a-Af9 complex represses αENaC by directly binding and regulating targeted histone H3 K79 hypermethylation at the specific subregions of αENaC promoter. Aldosterone decreases Dot1a-Af9 formation by impairing expression of Dot1a and Af9 and by inducing Sgk1, which, in turn, phosphorylates Af9 at S435 to weaken Dot1a-Af9 interaction. MR attenuates Dot1a-Af9 effect by competing with Dot1a for binding Af9. Af17 relieves repression by interfering with Dot1a-Af9 interaction and promoting Dot1a nuclear export. Af17^-/- mice exhibit defects in ENaC expression, renal Na^＋ retention, and blood pressure control. This review gives a brief summary of these novel fndings.展开更多
Three Gracilariopsis lemaneiformis strains,including wild type and high-temperature-resistant cultivars 981 and 2007,were studied with the changes in their photosynthetic pigment contents and related gene transcriptio...Three Gracilariopsis lemaneiformis strains,including wild type and high-temperature-resistant cultivars 981 and 2007,were studied with the changes in their photosynthetic pigment contents and related gene transcription levels under different light intensities(10,60,100,and 200μmolm^(−2)s^(−1)).The three G.lemaneiformis strains had the following photosynthetic pigments with high-to-low contents:phycoerythrin(PE),phycocyanin(PC),allophycocyanin(APC),and chlorophyll a(Chl a).Among the three strains,cultivar 981 had the highest PE content,followed by cultivar 2007.The PC and APC contents were similar among the three strains,but they were higher in cultivars 981 and 2007 than in the wild type.The Chl a contents in the three G.lemaneiformis strains were equal.A low light intensity(10μmolm^(−2)s^(−1))promoted photosynthetic pigment accumulation in G.lemaneiformis and improved the relative PE gene transcription(peA and peB)in a short period(≤6 d).A high light intensity decreased the PE content.PebA and PebB,which catalyzed phycoerythrobilin synthesis,showed no compensatory upregulation at a low light intensity among the strains except for the wild type.At a high light intensity,transcription levels of pebA and pebB in the three strains were upregulated.This study provided an experimental basis for elucidating the photosynthesis of G.lemaneiformis.As key genes of algal growth,photo-synthesis-related genes served as useful gene markers for screening elite varieties with good traits in breeding.Cultivar 2007 was superior to cultivar 981 in terms of maintaining high pigment levels in a wide range of light intensities,which is the most suitable for aquaculture.展开更多
This paper investigates the stochastic resonance （SR） induced by a multiplicative periodic signal in the gene transcriptional regulatory system with correlated noises. The expression of the signal-to-noise ratio （...This paper investigates the stochastic resonance （SR） induced by a multiplicative periodic signal in the gene transcriptional regulatory system with correlated noises. The expression of the signal-to-noise ratio （SNR） is derived. The results indicate that the existence of a maximum in SNR vs. the additive noise intensity α the multiplicative noise intensity D and the cross-correlated noise intensity λ is the identifying characteristic of the SR phenomenon and there is a critical phenomenon in the SNR as a function of λ, i.e., for the case of smaller values of noise intensity （α or D）, the SNR decreases as λ increases; however, for the case of larger values of noise intensity （α or D）, the SNR increases as λ increases.展开更多
The neural regeneration process is driven by a wide range of molecules and pathways. Adherens junctions are critical cellular junctions for the integrity of peripheral nerves. However, few studies have systematically ...The neural regeneration process is driven by a wide range of molecules and pathways. Adherens junctions are critical cellular junctions for the integrity of peripheral nerves. However, few studies have systematically characterized the transcript changes in the adherens junction pathway following injury. In this study, a rat model of sciatic nerve crush injury was established by forceps. Deep sequencing data were analyzed using comprehensive transcriptome analysis at 0, 1, 4, 7, and 14 days after injury. Results showed that most individual molecules in the adherens junctions were either upregulated or downregulated after nerve injury. The m RNA expression of ARPC1 B, ARPC3, TUBA8, TUBA1 C, CTNNA2, ACTN3, MET, HGF, NME1 and ARF6, which are involved in the adherens junction pathway and in remodeling of adherens junctions, was analyzed using quantitative real-time polymerase chain reaction. Most of these genes were upregulated in the sciatic nerve stump following peripheral nerve injury, except for CTNNA2, which was downregulated. Our findings reveal the dynamic changes of key molecules in adherens junctions and in remodeling of adherens junctions. These key genes provide a reference for the selection of clinical therapeutic targets for peripheral nerve injury.展开更多
Congenital cataract is a crystallin severe blinding disease and genetic factors in disease development are important. Crystallin growth is under a combination of genes and their products in time and space to complete ...Congenital cataract is a crystallin severe blinding disease and genetic factors in disease development are important. Crystallin growth is under a combination of genes and their products in time and space to complete the coordination role of the guidance. Congenital cataract-related genes, included crystallin protein gene (CRYAA, CRYAB, CRYBA1/A3, CRYBA4, CRYBB1, CRYBB2, CRYBB3, CRYGC, CRYGD, CRYGS), gap junction channel protein gene (GJA1, GJA3, GJA8), membrane protein gene (GJA3, GJA8, MIP, LIM2), cytoskeletal protein gene (BF-SP2), transcription factor genes (HSF4, MAF, PITX3, PAX6), ferritin light chain gene (FTL), fibroblast growth factor (FGF) and so on. Currently, there are about 39 genetic loci isolated to which primary cataracts have been mapped, although the number is constantly increasing and depends to some extent on definition. We summarized the recent advances on epidemiology and genetic locations of congenital cataract in this review.展开更多
Nuclear envelope proteins have important roles in chromatin organization and signal-dependent transcriptional regulation. A previous study reported that the inner nuclear membrane protein, Otefin （Ote）, was essentia...Nuclear envelope proteins have important roles in chromatin organization and signal-dependent transcriptional regulation. A previous study reported that the inner nuclear membrane protein, Otefin （Ote）, was essential for germline stem cell （GSC） maintenance via interaction with Smad complex. The interaction of Ore with the Smad complex recruits the barn locus to the nuclear periphery and subsequently results in bam transcriptional silencing, revealing that nuclear peripheral localization is essential for barn gene regulation. However, it remains unknown whether the nuclear peripheral localization is sufficient for barn silencing. To address this issue, we have established a tethering system, in which the Gal4 DNA binding domain （DBD） of the Flag：Gal4 DBD：Ote△LEM fusion protein physically interacts with the Gal4 binding sites upstream of bamP-gfp to artificially recruit the reporter gene gfp to the nuclear membrane. Our data demonstrated that the nuclear peripheral localization seemed to affect the expression of the target naked gene in S2 ceils. By contrast, in Drosophila germ cells, the nuclear membrane localization was not sufficient for gene silencing.展开更多
Human α1(Ⅰ), α2(Ⅰ) and α1(Ⅲ) cDNA probes and RNA dot hybridization were employed to quantitate collagen mRNA changes after adding silica dust into the media of human 2BS fibroblasts. At all dosages used (100, 20...Human α1(Ⅰ), α2(Ⅰ) and α1(Ⅲ) cDNA probes and RNA dot hybridization were employed to quantitate collagen mRNA changes after adding silica dust into the media of human 2BS fibroblasts. At all dosages used (100, 200, 500 and 1000μg), the α1(Ⅰ), α2(Ⅰ)and α1(Ⅲ) mRNA levels increased one day after dusting. At the same dosage of silica (100μg), α1(Ⅲ) mRNA increased earlier than type Ⅰ collagen mRNA did. The type Ⅰ and type Ⅲ collagen mRNA contents in the experimental groups were higher than those in control on days 3, 5, 7 and 9. The effect of ceruloplasmin (Cp) and fibronectin (Fn) on collagen mRNA synthesis was also studied, after adding silica dust, Cp or Fn into the media of human 2BS fibroblast. The results showed that Cp and Fn have stimulating effect on collagen mRNA production. When both Cp and silica dust were added into cell culture media, the collagen mRNA level was increased more than those of adding either Cp or silica dust alone. Similar situations were found for Fn. Cp (or Fn) synergism with silica dust on stimulating transcription of human collagen gene was suggested展开更多
We have investigated in the adiabatic limit the phenomenon of stochastic resonance in the gene transcriptional regulatory system subjected to an additive noise, a multiplicative noise, and a weakly periodic signal. Us...We have investigated in the adiabatic limit the phenomenon of stochastic resonance in the gene transcriptional regulatory system subjected to an additive noise, a multiplicative noise, and a weakly periodic signal. Using the general two-state approach for the asymmetry system, the analytic expression of signal-to-noise ratio is obtained. The effects of the additive noise intensity a, the multiplicative noise intensity D and the amplitude of input periodic signal A on the signal-to-noise ratio are analysed by numerical calculation. It is found that the existence of a maximum in the RSNR a and RSNR D plots is the identifying characteristic of the stochastic resonance phenomenon in the weakened noise intensity region. The stochastic resonance phenomena are restrained with increasing a and D, and enhanced with increasing A.展开更多
In order to investigate glucose metabolism pathways and their changes in Kunming mouse preimplantation 1-,2-,4-,8-cell,and morula embryos,the mRNA level for the genes involved in glucose metabolism was tested by neste...In order to investigate glucose metabolism pathways and their changes in Kunming mouse preimplantation 1-,2-,4-,8-cell,and morula embryos,the mRNA level for the genes involved in glucose metabolism was tested by nested RT-PCR on embryos at different development stages in vivo.These genes were glucose 6-phosphate dehydrogenase(G6PDH),phospho-fructokinase(PFK),and phosphoglucomutase(PGM),representing pentose phosphate pathway(PPP),glycolysis,and glycogensis and glycogenolysis respectively.Three sets of inner and outer primers were designed and synthesized based on cDNA sequences of G6PDH,PFK and PGM.RT-PCR results revealed that G6PDH gene transcription was found in Kunming mouse 1-8 cell embryos,and not in morula embryos;it indicated that 1-8 cell embryos may metabolize glucose by pentose phosphate pathway,but morula embryos can not do so.PFK gene transcription was found in 1-8 cell and morula embryos;it is probable that there exists glycolysis in those embryos.PGM gene transcription was not found in 1-8 cell and morula embryos,so glycogenesis and glycogenolysis in these embryos were not present.展开更多
[Objective]It is revealed whether the similar maize transcriptional activator in CBF1 gene is regulatory cold resistance gene to lay the foundation for breeding new transgenic Forage Maize Varieties with high cold res...[Objective]It is revealed whether the similar maize transcriptional activator in CBF1 gene is regulatory cold resistance gene to lay the foundation for breeding new transgenic Forage Maize Varieties with high cold resistance ability.[Methods]In the present paper,the transcriptional factor gene CBF1 was Successfully cloned by PCR from the leaves of Arabidopsis.The sequence was preliminarily analyzed and plant expression vector was constructed.Then with agrobacterium-mediated transgene technique,CBF1 gene was introduced into maize SAUMZ1.[Results]PCR assay revealed that the CBF1 gene was integrated in the maize grass SAUMZ1 genome.Under different low temperature treatment,the relative electrolyte leakage percentage of transgenic plant was lower than Control.[Conclusion] The results showed that the cold-resistance of maize grass SAUMZ1 enhanced after transforming CBF1 gene.展开更多
Expression of P-selectin in injured or activated endothelia cells serves as a permissive step towards leukocyte recruitment and perpetuation of inflammation in the pathogenesis of atherosclerosis.P-selectin can be ind...Expression of P-selectin in injured or activated endothelia cells serves as a permissive step towards leukocyte recruitment and perpetuation of inflammation in the pathogenesis of atherosclerosis.P-selectin can be induced by pro-inflammatory stimuli via the transcription factor NF-κB,but the epigenetic mechanisms remain incompletely understood.Previously we reported that myocardin-related transcription factor A（MRTF-A）mediates the transactivation of a slew of adhesion molecules by oxidized low-density lipoprotein（oxLDL）,likely through a crosstalk with brahma-related gene 1（BRGl）,a chromatin remodeling protein.Here,we show that MRTF-A was both sufficient and necessary for the transactivation of P-selectin gene in endothelial cells treated with TNF-α.Depletion of MRTF-A using small interfering RNA（siRNA）abrogated the binding of BRGl on the P-selectin promoter.Overexpression of BRG1 up-regulated the activity of P-selectin promoter activity while BRGl knockdown attenuated P-selectin expression.Finally,BRGl silencing suppressed the accumulation of acetylated histone H3 and methylated histone H3K4,and altered the binding of NF-κB on the P-selectin promoter.Therefore,our data demonstrate an essential role for MRTF-A and BRGl in P-selectin transactivation in endothelial cells.展开更多
Three rice varieties, Zhonghan 3, Shanyou 63 and Aizizhan, were used as materials in detecting differential active methyl cycle and transfer related gene expression in response to drought stress. The experiment was pe...Three rice varieties, Zhonghan 3, Shanyou 63 and Aizizhan, were used as materials in detecting differential active methyl cycle and transfer related gene expression in response to drought stress. The experiment was performed by gene chip and mRNA differential display technologies under the conditions of drought simulated with 10% PEG6000 solution. The results indicated that the methyl cycle could be activated in the leaves of Zhonghan 3 and Shanyou 63 but inhibited in the leaves of Aizizhan under drought stress. Furthermore, drought stress could induce the expression of a large number of methyltransferase genes, especially the transcription of Rubisco protein methylation related genes, which are beneficial for prevention of Rubisco protein oxidation and degradation, and drought stress could inhibit the transcription of DNA methyltransferase genes and histone methyltransferase genes. This result confirmed that the active methyl cycle and transfer related genes were involved in rice drought resistance.展开更多
BMP2 plays crucial roles in vertebrate developmental process and acts as a bone inducer during osteogenesis. We present here the molecular cloning of bmp2 cDNA from the marine flatfish Cynoglossus semilaevis, and the ...BMP2 plays crucial roles in vertebrate developmental process and acts as a bone inducer during osteogenesis. We present here the molecular cloning of bmp2 cDNA from the marine flatfish Cynoglossus semilaevis, and the analysis of bmp2 expression profiling and promoter function. The full length of bmp2 cDNA sequence is 2 048 bp,which encodes a protein of 422 amino acids. Tissue expression distribution of bmp2 was examined in 14 tissues of mature individuals by quantitative real time PCR（qRT-PCR）. The results revealed that bmp2 was expressed ubiquitously, and the highest expression level was detected in the spinal cord. Moreover, bmp2 expression levels were detected at 15 sampling time points of early developmental stages（egg, larva, juvenile and fingerling stages）.The highest expression level of bmp2 was observed at the gastrula stage, which was about ten times higher than those at the other three embryo stages. Whole-mount in situ hybridization showed that the bmp2 signal was strongly detected at the location of the crown-like larval fin, heart and liver, and slightly expressed in the notochord at one day post hatch（dph）; then the expression of bmp2 started to be concentrated in notochord at three dph. Subsequently, we characterized the 5′-flanking region of bmp2 by testing the promoter activity by Luciferase reporter assays. Positive regulatory region was detected at the location of –179 to ＋109. The predicted transcription factor binding sites（E-box binding factors, zinc finger transcription factor, etc.） in this region might participate in the transcriptional regulation of the bmp2 gene.展开更多
To investigate the expression levels of three Dsb protein genes, dsbB, dsbD and dsbG, at different time points post C. trachomatis infection, mouse fibroblast L2 cells were chosen to be infected with C. trachomatis se...To investigate the expression levels of three Dsb protein genes, dsbB, dsbD and dsbG, at different time points post C. trachomatis infection, mouse fibroblast L2 cells were chosen to be infected with C. trachomatis serovar F strain F/IC-Cal-13. C. trachomatis elementary body （EB）-infected L2 cells were harvested immediately after EB attachment onto the cells and every 4 hours post infection （hpi） till 44 hpi for total RNA preparation. RT-PCR assays were then employed to amplify cDNA with primer pairs which are specific to C. trachomatis dsb genes dsbB, dsbD, dsbG and tufA respectively. The relative expression levels of Dsb protein genes were evaluated as cDNA ratios of gene dsb to gene tufA. Our results showed that the transcription of dsbG started from 12 hpi and gradually increased till 44 hpi. The transcription of dsbB and dsbD were detected at 16 hpi and reached their peaks at 28 hpi and 24-28 hpi, respectively. Moreover, there was obvious transcription of dsbB at the later stage （44 hpi）, but none for dsbD at this time point. We came to the conclusion that the expression levels of the three Dsb protein genes are different during the developmental cycle of C. trachomatist. They may play a role in mid-to-late stage of the developmental cycle of C. trachomatis.展开更多
文摘Since transgene silencing was found in transgenic plants,many scholars have studied it extensively and considered that it has three functional mechanisms:post dependent gene silencing,transcriptional gene silencing,post transcriptional gene silencing.At the moment,people have mainly focused on the study of post transcriptional gene silencing and found its features:extensivity,conduction and peculiarity,also put forward some hypothesis for its mechanisms,for example,RNA threshold model,aberrant RNA model,inter or intra molecular base pairing model and so on.Furthermore,post transcriptional gene silencing is being applied in gene engineering of plants.Recently the people have found that post transcriptional gene silencing has bearing on capacity plants resisting virus.Many researchers have studied post transcriptional gene silencing,but there are some questions which need be solved in the future.This article summarizes progresses in features,mechanisms,applies of post transcriptional gene silencing about transgenic plants.
基金supported by the Provincial Natural Science Foundation of Zhejiang,China(No.LY22C190001)the Ningbo Science and Technology Research Projects,China(No.2019B10006)the earmarked fund for CARS-49,and the Ningbo Public Welfare Science and Technology Program(No.2022S161).
文摘Isochrysis zhanjiangensis is a dietary microalga renowned for its high content of polyunsaturated fatty acids(PUFAs).However,research on the genes essential for PUFA synthesis in Isochrysis zhanjiangensis is limited.This study successfully isolated twoΔ9 fatty acid desaturase genes,IZ-delta9-1 and IZ-delta9-2,from Isochrysis zhanjiangensis,which are classified as acyl-lipid desaturases based on phylogenetic analysis.When heterologously expressed in yeast,both genes were confirmed to catalyze the conversion of C16:0 and C18:0 into C16:1 and C18:1,respectively.Furthermore,the impacts of environmental factors on algal growth,fatty acid composition,and transcription levels were explored.Using gas chromatography-mass spectrometry(GC-MS),the fatty acid profiles of I.zhanjiangensis were evaluated.The findings showed that under low temperature(LT)and low nitrogen(LN)conditions,the saturated fatty acids(SFAs)content decreased,and the monounsaturated(MUFAs)and unsaturated fatty acids(UFAs)contents increased.Changes in salinity had a minimal impact on the fatty acid composition.The qPCR analysis revealed that high temperature(HT)and high salt(HS)increased the transcription of IZ-delta9-1,while low nitrogen(LN)and high nitrogen(HN)decreased it.Unlike IZ-delta9-1,the transcription of IZ-delta9-2 significantly increased under both low and high temperature treatments,especially in LT groups.Moreover,compared to the control,the transcription levels of IZ-delta9-1 decreased under improper salinity and nitrogen concentrations.This study is helpful for understanding the fatty acid synthesis pathway in I.zhanjiangensis.
基金supported by the National Natural Science Foundation of China (30971773)the Natural Science Foundation of Hebei Province,China (C2011204031)the Key Laboratory of Crop Growth Regulation of Hebei Province,China
文摘Based on sequencing of part clones in a root subtractive cDNA library, an expressed sequence tag （EST） sharing high similarity to a rice C2H2 zinc finger transcription factor （ZFP15） was obtained in wheat. Through bioinformatics approach, the wheat C2H2-type ZFP gene referred to TaZFP15 has been identified and characterized. As a full-length cDNA of 670 bp, TaZFP15 has an open reading frame of 408 bp and encodes a 135-aa polypeptide. TaZFP15 contains two C2H2 zinc finger domains and each one has a conserved motif QALGGH. The typical L-box, generally identified in the C2H2 type transcription factors, has also been found in TaZFP15. Phylogenetic analysis suggested that TaZFP15 shares high similarities with rice ZFP15 （GenBank accession no. AY286473）, maize ZFP （GenBank accession no. NM_001159094） and a subset of other zinc-finger transcription factor genes in plant species. The expression of TaZFP15 was up-regulated by starved-Pi stress, showing a pattern to be gradually elevated along with the progression of the Pi-stress in a 23-h treatment regime. Similarly, the transcripts of TaZFP15 in roots were also induced by nitrogen deficiency, and abiotic stresses of drought and salinity. No responses of TaZFP15 were detected in roots to nutrition deficiencies of P, Zn, and Ca, and the external treatment of abscisic acid （ABA）. TaZFP15 could be specifically amplified in genome A, B, and D, and without variability in the sequences, suggesting that TaZFP15 has multi-copies in the homologous hexaploid species. Transgenic analysis in tobacco revealed that up-regulation of TaZFP15 could significantly improve plant dry mass accumulation via increasing the plant phosphorus acquisition capacity under Pi-deficiency condition. The results suggested that TaZFP15 is involved in mediation of signal transductions of diverse external stresses.
基金supported by a project grant from the Education Department of Heilongjiang Province, China (Grant No. 11511248).
文摘ICE1, an Arabidopsis thaliana transcription factor gene, was cloned by RT-PCR and successfully transformed into rice variety Kenjiandao 10 by the Agrobacterium-mediated transformation method. PCR amplification and Southern blot analysis indicated that ICE1 had been integrated into rice genome. Compared with the non-transgenic plants, the transgenic plants exhibited high resistance to hygromycin B and were consistent with the Mendelian inheritance of a single copy of the transgenic ICE1. Under the low temperature stress, the transgenic plants showed the lower mortality rate and the increased proline content. These results suggest that the Arabidopsis ICE1 is functional in rice and the over-expression of ICE1 improves the tolerance to cold stress in rice.
文摘Objective: To study the molecular mechanisms of TNF--a expression induced by lipopolysaccharide (LPS) for exploring novel methods to prevent or treat clinical patients with endotoxic shock. Methods:Protein kinase assay was used to detect the kinase activity stimulated by LPS; Con focal laser scan technique was used to show the translocation of p38 on the activation; RT PCR and reporter gene system were used to study the molecular mechanism of TNF -a gene transcription. Results: In RAW cells it was found that p38 was activated on the stimulation of LPS. and activated p38 moved into nucleus from cytosol; TNF--a mRNA increased on the stimulation of LPS and the increased promoter transactivity induced by LPS could be inhibited significantly by specific inhibitor for p38. Conclusion: p38 mitogen activated protein kinase (MAPK ) was activated by the stimulation of LPS,which brought about its entry to the nucleus to act on transcription factors to regulate cellular processes. p38 MAPK Is an important regulator of TNF--a gene expression induced by LPS.
基金Supported by National Institutes of Health Grant 2R01 DK080236 06A1
文摘The epithelial Na^＋ channel （ENaC） consists of α, β, γ subunits. Its expression and function are regulated by aldosterone at multiple levels including transcription. ENaC plays a key role in Na^＋ homeostasis and blood pressure. Mutations in ENaC subunit genes result in hypertension or hypotension, depending on the nature of the mutations. Transcription of αENaC is considered as the rate-limiting step in the formation of functional ENaC. As an aldosterone target gene, αENaC is activated upon aldosterone- mineralocorticoid receptor binding to the cis-elements in the αENaC promoter, which is packed into chromatin. However, how aldosterone alters chromatin structure to induce changes in transcription is poorly understood. Studies by others and us suggest that Dot1a-Af9 complex represses αENaC by directly binding and regulating targeted histone H3 K79 hypermethylation at the specific subregions of αENaC promoter. Aldosterone decreases Dot1a-Af9 formation by impairing expression of Dot1a and Af9 and by inducing Sgk1, which, in turn, phosphorylates Af9 at S435 to weaken Dot1a-Af9 interaction. MR attenuates Dot1a-Af9 effect by competing with Dot1a for binding Af9. Af17 relieves repression by interfering with Dot1a-Af9 interaction and promoting Dot1a nuclear export. Af17^-/- mice exhibit defects in ENaC expression, renal Na^＋ retention, and blood pressure control. This review gives a brief summary of these novel fndings.
基金This research was supported by the National Natural Sci-ence Foundation of China(No.31872555)the China Agri-culture Research System(No.CARS-50)the Key Pro-gram of Science and Technology Innovation Ningbo(No.2019B10009).
文摘Three Gracilariopsis lemaneiformis strains,including wild type and high-temperature-resistant cultivars 981 and 2007,were studied with the changes in their photosynthetic pigment contents and related gene transcription levels under different light intensities(10,60,100,and 200μmolm^(−2)s^(−1)).The three G.lemaneiformis strains had the following photosynthetic pigments with high-to-low contents:phycoerythrin(PE),phycocyanin(PC),allophycocyanin(APC),and chlorophyll a(Chl a).Among the three strains,cultivar 981 had the highest PE content,followed by cultivar 2007.The PC and APC contents were similar among the three strains,but they were higher in cultivars 981 and 2007 than in the wild type.The Chl a contents in the three G.lemaneiformis strains were equal.A low light intensity(10μmolm^(−2)s^(−1))promoted photosynthetic pigment accumulation in G.lemaneiformis and improved the relative PE gene transcription(peA and peB)in a short period(≤6 d).A high light intensity decreased the PE content.PebA and PebB,which catalyzed phycoerythrobilin synthesis,showed no compensatory upregulation at a low light intensity among the strains except for the wild type.At a high light intensity,transcription levels of pebA and pebB in the three strains were upregulated.This study provided an experimental basis for elucidating the photosynthesis of G.lemaneiformis.As key genes of algal growth,photo-synthesis-related genes served as useful gene markers for screening elite varieties with good traits in breeding.Cultivar 2007 was superior to cultivar 981 in terms of maintaining high pigment levels in a wide range of light intensities,which is the most suitable for aquaculture.
基金Project supported by the National Natural Science Foundation of China (Grant No.10865006)the Science Foundation of Yunnan University (Grant No.2009A01Z)
文摘This paper investigates the stochastic resonance （SR） induced by a multiplicative periodic signal in the gene transcriptional regulatory system with correlated noises. The expression of the signal-to-noise ratio （SNR） is derived. The results indicate that the existence of a maximum in SNR vs. the additive noise intensity α the multiplicative noise intensity D and the cross-correlated noise intensity λ is the identifying characteristic of the SR phenomenon and there is a critical phenomenon in the SNR as a function of λ, i.e., for the case of smaller values of noise intensity （α or D）, the SNR decreases as λ increases; however, for the case of larger values of noise intensity （α or D）, the SNR increases as λ increases.
基金supported by the National Natural Science Foundation of China,No.31700926the Priority Academic Program Development of Jiangsu Higher Education Institutions of China
文摘The neural regeneration process is driven by a wide range of molecules and pathways. Adherens junctions are critical cellular junctions for the integrity of peripheral nerves. However, few studies have systematically characterized the transcript changes in the adherens junction pathway following injury. In this study, a rat model of sciatic nerve crush injury was established by forceps. Deep sequencing data were analyzed using comprehensive transcriptome analysis at 0, 1, 4, 7, and 14 days after injury. Results showed that most individual molecules in the adherens junctions were either upregulated or downregulated after nerve injury. The m RNA expression of ARPC1 B, ARPC3, TUBA8, TUBA1 C, CTNNA2, ACTN3, MET, HGF, NME1 and ARF6, which are involved in the adherens junction pathway and in remodeling of adherens junctions, was analyzed using quantitative real-time polymerase chain reaction. Most of these genes were upregulated in the sciatic nerve stump following peripheral nerve injury, except for CTNNA2, which was downregulated. Our findings reveal the dynamic changes of key molecules in adherens junctions and in remodeling of adherens junctions. These key genes provide a reference for the selection of clinical therapeutic targets for peripheral nerve injury.
文摘Congenital cataract is a crystallin severe blinding disease and genetic factors in disease development are important. Crystallin growth is under a combination of genes and their products in time and space to complete the coordination role of the guidance. Congenital cataract-related genes, included crystallin protein gene (CRYAA, CRYAB, CRYBA1/A3, CRYBA4, CRYBB1, CRYBB2, CRYBB3, CRYGC, CRYGD, CRYGS), gap junction channel protein gene (GJA1, GJA3, GJA8), membrane protein gene (GJA3, GJA8, MIP, LIM2), cytoskeletal protein gene (BF-SP2), transcription factor genes (HSF4, MAF, PITX3, PAX6), ferritin light chain gene (FTL), fibroblast growth factor (FGF) and so on. Currently, there are about 39 genetic loci isolated to which primary cataracts have been mapped, although the number is constantly increasing and depends to some extent on definition. We summarized the recent advances on epidemiology and genetic locations of congenital cataract in this review.
基金supported by the Postdoctoral Science Foundation of China(No.20090460517)
文摘Nuclear envelope proteins have important roles in chromatin organization and signal-dependent transcriptional regulation. A previous study reported that the inner nuclear membrane protein, Otefin （Ote）, was essential for germline stem cell （GSC） maintenance via interaction with Smad complex. The interaction of Ore with the Smad complex recruits the barn locus to the nuclear periphery and subsequently results in bam transcriptional silencing, revealing that nuclear peripheral localization is essential for barn gene regulation. However, it remains unknown whether the nuclear peripheral localization is sufficient for barn silencing. To address this issue, we have established a tethering system, in which the Gal4 DNA binding domain （DBD） of the Flag：Gal4 DBD：Ote△LEM fusion protein physically interacts with the Gal4 binding sites upstream of bamP-gfp to artificially recruit the reporter gene gfp to the nuclear membrane. Our data demonstrated that the nuclear peripheral localization seemed to affect the expression of the target naked gene in S2 ceils. By contrast, in Drosophila germ cells, the nuclear membrane localization was not sufficient for gene silencing.
文摘Human α1(Ⅰ), α2(Ⅰ) and α1(Ⅲ) cDNA probes and RNA dot hybridization were employed to quantitate collagen mRNA changes after adding silica dust into the media of human 2BS fibroblasts. At all dosages used (100, 200, 500 and 1000μg), the α1(Ⅰ), α2(Ⅰ)and α1(Ⅲ) mRNA levels increased one day after dusting. At the same dosage of silica (100μg), α1(Ⅲ) mRNA increased earlier than type Ⅰ collagen mRNA did. The type Ⅰ and type Ⅲ collagen mRNA contents in the experimental groups were higher than those in control on days 3, 5, 7 and 9. The effect of ceruloplasmin (Cp) and fibronectin (Fn) on collagen mRNA synthesis was also studied, after adding silica dust, Cp or Fn into the media of human 2BS fibroblast. The results showed that Cp and Fn have stimulating effect on collagen mRNA production. When both Cp and silica dust were added into cell culture media, the collagen mRNA level was increased more than those of adding either Cp or silica dust alone. Similar situations were found for Fn. Cp (or Fn) synergism with silica dust on stimulating transcription of human collagen gene was suggested
基金Project supported by the National Natural Science Foundation of China (Grant No. 10865006)the Science Foundation of the Education Bureau of Shaanxi Province of China (Grant No. 09JK331)the Science Foundation of Baoji University of Science and Arts of China (Grant No. Zk0834)
文摘We have investigated in the adiabatic limit the phenomenon of stochastic resonance in the gene transcriptional regulatory system subjected to an additive noise, a multiplicative noise, and a weakly periodic signal. Using the general two-state approach for the asymmetry system, the analytic expression of signal-to-noise ratio is obtained. The effects of the additive noise intensity a, the multiplicative noise intensity D and the amplitude of input periodic signal A on the signal-to-noise ratio are analysed by numerical calculation. It is found that the existence of a maximum in the RSNR a and RSNR D plots is the identifying characteristic of the stochastic resonance phenomenon in the weakened noise intensity region. The stochastic resonance phenomena are restrained with increasing a and D, and enhanced with increasing A.
基金National Natural Science Foundation of China(39600106)
文摘In order to investigate glucose metabolism pathways and their changes in Kunming mouse preimplantation 1-,2-,4-,8-cell,and morula embryos,the mRNA level for the genes involved in glucose metabolism was tested by nested RT-PCR on embryos at different development stages in vivo.These genes were glucose 6-phosphate dehydrogenase(G6PDH),phospho-fructokinase(PFK),and phosphoglucomutase(PGM),representing pentose phosphate pathway(PPP),glycolysis,and glycogensis and glycogenolysis respectively.Three sets of inner and outer primers were designed and synthesized based on cDNA sequences of G6PDH,PFK and PGM.RT-PCR results revealed that G6PDH gene transcription was found in Kunming mouse 1-8 cell embryos,and not in morula embryos;it indicated that 1-8 cell embryos may metabolize glucose by pentose phosphate pathway,but morula embryos can not do so.PFK gene transcription was found in 1-8 cell and morula embryos;it is probable that there exists glycolysis in those embryos.PGM gene transcription was not found in 1-8 cell and morula embryos,so glycogenesis and glycogenolysis in these embryos were not present.
基金Funded by "Twelfth five-year" rural areas of science and technology plan project "south high quality forage grass efficient production and processing using the key technology research and integrated demonstration bad17b03 (2011) and "Gongan gus beef cattle production integrated technology demonstration to promote" (12417)
文摘[Objective]It is revealed whether the similar maize transcriptional activator in CBF1 gene is regulatory cold resistance gene to lay the foundation for breeding new transgenic Forage Maize Varieties with high cold resistance ability.[Methods]In the present paper,the transcriptional factor gene CBF1 was Successfully cloned by PCR from the leaves of Arabidopsis.The sequence was preliminarily analyzed and plant expression vector was constructed.Then with agrobacterium-mediated transgene technique,CBF1 gene was introduced into maize SAUMZ1.[Results]PCR assay revealed that the CBF1 gene was integrated in the maize grass SAUMZ1 genome.Under different low temperature treatment,the relative electrolyte leakage percentage of transgenic plant was lower than Control.[Conclusion] The results showed that the cold-resistance of maize grass SAUMZ1 enhanced after transforming CBF1 gene.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20141498)a grant from Jiangsu Jiankang Vocational University(JKC201505)
文摘Expression of P-selectin in injured or activated endothelia cells serves as a permissive step towards leukocyte recruitment and perpetuation of inflammation in the pathogenesis of atherosclerosis.P-selectin can be induced by pro-inflammatory stimuli via the transcription factor NF-κB,but the epigenetic mechanisms remain incompletely understood.Previously we reported that myocardin-related transcription factor A（MRTF-A）mediates the transactivation of a slew of adhesion molecules by oxidized low-density lipoprotein（oxLDL）,likely through a crosstalk with brahma-related gene 1（BRGl）,a chromatin remodeling protein.Here,we show that MRTF-A was both sufficient and necessary for the transactivation of P-selectin gene in endothelial cells treated with TNF-α.Depletion of MRTF-A using small interfering RNA（siRNA）abrogated the binding of BRGl on the P-selectin promoter.Overexpression of BRG1 up-regulated the activity of P-selectin promoter activity while BRGl knockdown attenuated P-selectin expression.Finally,BRGl silencing suppressed the accumulation of acetylated histone H3 and methylated histone H3K4,and altered the binding of NF-κB on the P-selectin promoter.Therefore,our data demonstrate an essential role for MRTF-A and BRGl in P-selectin transactivation in endothelial cells.
基金supported by the Open Research Fund Program of Jiangsu Key Laboratory of Crop Cultivation and Physiology,China (Grant No.0273880036)
文摘Three rice varieties, Zhonghan 3, Shanyou 63 and Aizizhan, were used as materials in detecting differential active methyl cycle and transfer related gene expression in response to drought stress. The experiment was performed by gene chip and mRNA differential display technologies under the conditions of drought simulated with 10% PEG6000 solution. The results indicated that the methyl cycle could be activated in the leaves of Zhonghan 3 and Shanyou 63 but inhibited in the leaves of Aizizhan under drought stress. Furthermore, drought stress could induce the expression of a large number of methyltransferase genes, especially the transcription of Rubisco protein methylation related genes, which are beneficial for prevention of Rubisco protein oxidation and degradation, and drought stress could inhibit the transcription of DNA methyltransferase genes and histone methyltransferase genes. This result confirmed that the active methyl cycle and transfer related genes were involved in rice drought resistance.
基金The Special Scientific Research Funds for Central Non-profit Institutes,Chinese Academy of Fishery Sciences under contract No.2016RC-LX02the National Natural Science Foundation of China under contract No.31201981
文摘BMP2 plays crucial roles in vertebrate developmental process and acts as a bone inducer during osteogenesis. We present here the molecular cloning of bmp2 cDNA from the marine flatfish Cynoglossus semilaevis, and the analysis of bmp2 expression profiling and promoter function. The full length of bmp2 cDNA sequence is 2 048 bp,which encodes a protein of 422 amino acids. Tissue expression distribution of bmp2 was examined in 14 tissues of mature individuals by quantitative real time PCR（qRT-PCR）. The results revealed that bmp2 was expressed ubiquitously, and the highest expression level was detected in the spinal cord. Moreover, bmp2 expression levels were detected at 15 sampling time points of early developmental stages（egg, larva, juvenile and fingerling stages）.The highest expression level of bmp2 was observed at the gastrula stage, which was about ten times higher than those at the other three embryo stages. Whole-mount in situ hybridization showed that the bmp2 signal was strongly detected at the location of the crown-like larval fin, heart and liver, and slightly expressed in the notochord at one day post hatch（dph）; then the expression of bmp2 started to be concentrated in notochord at three dph. Subsequently, we characterized the 5′-flanking region of bmp2 by testing the promoter activity by Luciferase reporter assays. Positive regulatory region was detected at the location of –179 to ＋109. The predicted transcription factor binding sites（E-box binding factors, zinc finger transcription factor, etc.） in this region might participate in the transcriptional regulation of the bmp2 gene.
文摘To investigate the expression levels of three Dsb protein genes, dsbB, dsbD and dsbG, at different time points post C. trachomatis infection, mouse fibroblast L2 cells were chosen to be infected with C. trachomatis serovar F strain F/IC-Cal-13. C. trachomatis elementary body （EB）-infected L2 cells were harvested immediately after EB attachment onto the cells and every 4 hours post infection （hpi） till 44 hpi for total RNA preparation. RT-PCR assays were then employed to amplify cDNA with primer pairs which are specific to C. trachomatis dsb genes dsbB, dsbD, dsbG and tufA respectively. The relative expression levels of Dsb protein genes were evaluated as cDNA ratios of gene dsb to gene tufA. Our results showed that the transcription of dsbG started from 12 hpi and gradually increased till 44 hpi. The transcription of dsbB and dsbD were detected at 16 hpi and reached their peaks at 28 hpi and 24-28 hpi, respectively. Moreover, there was obvious transcription of dsbB at the later stage （44 hpi）, but none for dsbD at this time point. We came to the conclusion that the expression levels of the three Dsb protein genes are different during the developmental cycle of C. trachomatist. They may play a role in mid-to-late stage of the developmental cycle of C. trachomatis.
