promoter

摘要： The neuronal differentiation of mesenchymal stem cells offers a new strategy for the treatment of neurological disorders.Thus,there is a need to identify a noninvasive and sensitive in vivo imaging approach for real-time monitoring of transplanted stem cells.Our previous study confirmed that magnetic resonance imaging,with a focus on the ferritin heavy chain 1 reporter gene,could track the proliferation and differentiation of bone marrow mesenchymal stem cells that had been transduced with lentivirus carrying the ferritin heavy chain 1 reporter gene.However,we could not determine whether or when bone marrow mesenchymal stem cells had undergone neuronal differentiation based on changes in the magnetic resonance imaging signal.To solve this problem,we identified a neuron-specific enolase that can be differentially expressed before and after neuronal differentiation in stem cells.In this study,we successfully constructed a lentivirus carrying the neuron-specific enolase promoter and expressing the ferritin heavy chain 1 reporter gene;we used this lentivirus to transduce bone marrow mesenchymal stem cells.Cellular and animal studies showed that the neuron-specific enolase promoter effectively drove the expression of ferritin heavy chain 1 after neuronal differentiation of bone marrow mesenchymal stem cells;this led to intracellular accumulation of iron and corresponding changes in the magnetic resonance imaging signal.In summary,we established an innovative magnetic resonance imaging approach focused on the induction of reporter gene expression by a neuron-specific promoter.This imaging method can be used to noninvasively and sensitively detect neuronal differentiation in stem cells,which may be useful in stem cell-based therapies.

摘要： BACKGROUND Helicobacter pylori(H.pylori)is a ubiquitous bacterium that affects nearly half of the world’s population with a high morbidity and mortality rate.Polymorphisms within the tumor necrosis factor-alpha(TNF-A)promoter region are considered a possible genetic basis for this disease.AIM To functionally characterize the genetic variations in the TNF-A 5’-region(-584 to+107)of Sudanese patients infected with H.pylori using in silico tools.METHODS An observational study was carried out in major public and private hospitals in Khartoum state.A total of 122 gastric biopsies were taken from patients who had been referred for endoscopy.Genomic DNA was extracted.Genotyping of the TNF-A-1030 polymorphism was performed using PCR with confronting two-pair primer to investigate its association with the susceptibility to H.pylori infection in the Sudanese population.Furthermore,Sanger sequencing was applied to detect single nucleotide polymorphisms in the 5’-region(-584 to+107)of TNF-A in H.pylori-infected patients.Bioinformatics analyses were used to predict whether these mutations would alter transcription factor binding sites or composite regulatory elements in this region.A comparative profiling analysis was conducted in 11 species using the ECR browser and multiple-sequence local alignment and visualization search engine to investigate the possible conservation.Also,a multivariate logistic regression model was constructed to estimate odds ratios and their 95%confidence intervals for the association between TNF-A-1030,sociodemographic characteristics and H.pylori infection.Differences were statistically significant if PA,-76)was located at the in silico-predicted promoter region(-146 to+10),and it was predicted to alter transcription factor binding sites and composite regulatory elements.A novel mutation(A>T,+27)was detected in the 5’untranslated region,and it could affect the post-transcriptional regulatory pathways.Genotyping of TNF-A-1030 showed a lack of significant association between-1030T and susceptibility to H.pylori and gastric cancer in the studied population(P=0.1756)and(P=0.8116),respectively.However,a significant association was detected between T/C genotype and H.pylori infection(39.34%vs 19.67%,odds ratio=2.69,95%confidence interval:1.17-6.17,P=0.020).Mammalian conservation was observed for the(-146 to+10)region in chimpanzee(99.4%),rhesus monkey(95.6%),cow(91.8%),domesticated dog(89.3%),mouse(84.3%),rat(82.4%)and opossum(78%).CONCLUSION Computational analysis was a valuable method for understanding TNF-A gene expression patterns and guiding further in vitro and in vivo experimental validation.

摘要： Soybean(Glycine max)is short-day(SD)plant.Flowering time is a key agronomic trait that determines the transition from vegetative to reproductive growth.The study on the expression and regulation mechanism of flowering time gene in soybean photoperiod control of flowering pathway is particularly theoretically significant for soybean genetic improvement.In this study,a dual-luciferase reporter gene system with the GmFT2a gene promoter as promoter sequence was constructed,and the method of Agrobacterium tumefaciens injection into tobacco leaves was selected to study the effects of long and short days on the activity of the GmFT2a gene promoter.The results of transient expression analysis showed that the GmFT2a promoter was strongly induced under the SD conditions in tobacco.Furthermore,analysis of the GmFT2a promoter sequence revealed several cis-acting elements,including G-Box,Box 4,GT1-motif and TCT-motif by PlantCARE search.It was speculated that these elements might promote the expression of GmFT2a gene in the SDs and played a role in promoting flowering.The results of this study provided a basis for a better understanding of the function of the GmFT2a gene and further exploration of the complex flowering mechanism of soybean.

摘要： The knowledge generated from the identification of plant promoters has been very important for plant biotechnology development. The use of promoters in transgenic plants allows a reasonable level of regulating protein expression. With the application of reporter genes, such as gusA (uidA,) the production of a colored protein, β-glucuronidase, can be detected and measured both qualitatively and quantitatively, and the activity of the promoter can be assessed. In this work we use a promoter of an abundant banana fruit protein gene Musa acuminata Acidic Chitinase class III a monocot species, to drive expression of gusA in a dicot species, like tomato. We evaluated the monocot promoter capabilities by localizing and quantifying β-glucuronidase (GUS) expression through fluorometric assays during tomato fruit ripening. Our results suggest that this promoter could be used for specifically strong fruit protein expression in dicot plants.

摘要： The divergence and continuous evolution of plants and animals contribute to ecological diversity.Promoters and transcription factors(TFs) are key determinants of gene regulation and transcription throughoutlife.However,theevolutionary trajectories and relationships of promoters and TFs are still poorly understood. Here, we conducted extensive analysis of large-scale multi-omics sequences in 420 animal species and 223 plant species spanning nearly a billion years of evolutionary history. Results showed that promoter GC-contentandTFisoelectricpoints,as features/signatures that accompany long biological evolution, exhibited increasing growth in animal cells but a decreasing trend in plant cells. Furthermore, the evolutionary trajectories of promoter and TF signatures in the animal kingdom provided further evidence that Mammalia as well as Aves evolved directly from the ancestor Reptilia. The strong correlation between promoter and TF signatures indicates that promoters and TFs formed antagonistic coevolution in the animal kingdom, but mutualistic coevolution in the plant kingdom. The distinct coevolutionary patterns potentially drive the plant-animal divergence, divergent evolution and ecological diversity.

摘要： Carotenoids are indispensable for both human health and plant survival.Citrus,is one of the fruit crops richest in carotenoid compounds,with approximately 115 kinds of carotenoids;tremendous diversity in carotenoids composition and concentration exists among various species,showing different colors from nearly white to crimson.The carotenoid biosynthetic pathway and the key carotenogenic genes have been identified in citrus;however,the underlying regulatory mechanisms remain unclear.In this study,among the main species of genus Citrus(primitive,wild,and cultivated),we detected carotenoids in flavedo using High-Performance Liquid Chromatography,and analyzed variations in cis-acting elements in the promoters of key carotenoid pathway genes.Intriguingly,both carotenoid composition and content were generally increased during the evolution of citrus,and the corresponding variations in the promoters were identified,including the gain or loss of critical environmental stress-responsive elements and hormone-responsive elements,which are closely associated with carotenoid enhancement.In addition,pummelo has the most heat-responsive elements,but the Mangshan mandarin does not have this element in the promoters of PSY,which is highly related to their geographical origin and indicate that temperature is a critical environmental signal influencing carotenoid accumulation.Moreover,the abscisic acid-responsive motif was rich in almost all the seven species,but the ethylene-responsive motif was deficient,which demystified the unique phytohormone regulation mechanism of carotenoid accumulation in citrus.Overall,our study provides new insights into the molecular regulatory mechanism of carotenoid enhancement in the evolution of citrus,which can facilitate breeding and cultivation efforts to improve the nutritional quality and esthetic value in citrus and hopefully other fruit crops.

摘要： Laccases, multicopper oxidoreductases, are mainly produced in white-rot fungi and are considered as ideal green catalysts in industrial and biotechnological applications. However, the development of laccases is limited due to the slow growth of natural laccase producing strains and the low expression levels of laccases. In this study, we designed three regulation strategies for laccase gene expression in the model fungus Aspergillus nidulans. By introducing various promoters in front of the laccase gene pslcc from the white-rot fungus Pycnoporus sanguineus, we found that the laccase gene with the original promoter had effective expression in A. nidulans. Using the previously identified transcription factor RsmA regulatory mechanism, the aflR promoter was inserted into the pslcc expression vectors, and the laccase production was 15-fold higher in the strain overexpressing of RsmA compared to the control strain. To improve the laccase yield, the dipeptidyl-peptidase DppV, aspartic protease PepA and mannosyltransferase Mnn9 were successfully deleted in the A. nidulans host. The laccase activities were increased approximately 8-fold and 13-fold in the double deletions strains of Δmnn9ΔpepA and ΔdppVΔpepA over the control strains, respectively.Taken together, these results not only demonstrate an efficient system for heterologous protein production in the model fungus A.nidulans but also provide a general approach to applying regulatory methods to control gene expression.

摘要： Objective: To study the association between post-traumatic stress disorder (PTSD) and serotonin transporter promoter (5-HTTLPR) gene polymorphism in Han children in Hainan;to explore the genetic mechanism of PTSD in children. Methods: 50 patients with post-traumatic stress disorder and healthy children in Han nationality in Hainan were selected. Detection of 5-HTTLPR gene polymorphism by polymerase chain reaction (PCR) and amplified fragment length polymorphism, the genotype and allele frequencies were analyzed using a case-control association analysis method. Results: There were 4, 14 and 32 cases of LL, SL and SS in the post-traumatic stress disorder group of Hainan Han children, and 13, 20 and 17 cases in the control group. From the perspective of gene frequency, the L gene of post-traumatic stress disorder appeared 22.0%, and S appeared 78.0%. In the control group, L appeared 46.0%, and S appeared 54.0%. There were significant differences in genotype and gene frequency (P Conclusion: The 5-HTTLPR gene polymorphism in Hainan Han children may be associated with post-traumatic stress disorder.

摘要： Identification of promoters and their regulatory elements are the most important phases in bioinformatics. To understand the regulation of gene expression, identification, and analysis of promoters region, motif and CpG islands are the most important steps. The accurate prediction of promoter’s is basic for proper interpretation of gene expression patterns, construction and understanding of genetic regulatory system. Therefore, the objective of this study was to analyze the promoter region, motif such as a transcription factor and CpG islands in AraC family transcriptional regulator ACP92 genes of Herbaspirillum seropedicae. The analysis was carried out by identifying transcription start sites in ACP92 genome sequences taken from the H. seropedicae assembly of NCBI genome browser, and 29 ACP92 genes sequences. Accordingly, transcription start sites (TSS) were identified, and the result indicated that 37.9% had more than one TSS whereas only 62.1% had one TSS. In the analysis, seven motifs were identified from the thought sequences and MV6 was revealed the common promoter motif for all (100%) in H. seropedicae ACP92 gene that serves as binding sites for transcription factors which shared a minimum of 48.27%. Based on a common motif MV6 to find out similar motifs using TOMTOM from the databases of prokaryotes DNA, most of them are transcription factors of fur family. The others are bacterial histone-like protein family, matp and sigma-54 factor family also transcription factor families that are binding candidate to MV6. H. seropedicae ACP92 genes are CpG Island which implies that the regulation of gene expression plays an important role.