1.Studies on expression, purification, crystal growth and optimization of putative transcription factor LytR from Streptococcus pneumoniae.
Xun MIN ; Wen ZHONG ; Shasha ZHAO ; Jie DONG ; Shanshan DONG ; Aie ZHOU ; Wenjuan YAN ; Deqiang WANG
Journal of Biomedical Engineering 2013;30(4):812-821
The aim of the present study was to obtain the crystal of transcription factor LytR of streptococcus pneumoniae for X-ray crystal structure and function analysis. The LytR gene of D39 strains from Streptococcus pneumoniae (S. pn) was cloned into the prokaryotic expression vector pET32a(+), then overexpression was obtained in the E. coli BL21 (DE3) through transformation of the recombinant plasmid that had been verified by colony PCR and sequencing. Soluble fusion protein with His-tag highly expressed by the induction of 0.5 mmol/L IPTG and was purified by a three step procedure, the purity of the purified LytR recombinant protein was over 90%. Preliminary screening of crystallization conditions was performed using the hanging-drop vapour-diffusing method with Hampton Crystal screen and PEG screen kits. The protein crystals X-ray diffraction data were collected from a single crystal and more stick crystals whose X-ray diffraction reached 4.0 A were obtained. These works laid the foundation for further research on the 3D structure of putative transcription factor LytR and its biological aspects.
Bacterial Proteins
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biosynthesis
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genetics
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isolation & purification
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Escherichia coli
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genetics
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metabolism
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Recombinant Proteins
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biosynthesis
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genetics
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isolation & purification
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Streptococcus pneumoniae
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genetics
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metabolism
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Transcription Factors
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biosynthesis
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genetics
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isolation & purification
2.Research progress of the regulation on active compound biosynthesis by the bHLH transcription factors in plants.
Xin ZHANG ; Jing-Yuan SONG ; Yuan-Lei HU ; Jiang XU ; Zhi-Chao XU ; Ai-Ji JI ; Hong-Mei LUO ; Shi-Lin CHEN
Acta Pharmaceutica Sinica 2014;49(4):435-442
Transcription factor is one of the key factors in the regulation of gene expression at the transcriptional level. It plays an important role in plant growth, active components biosynthesis and response to environmental change. This paper summarized the structure and classification of bHLH transcription factors and elaborated the research progress of bHLH transcription factors which regulate the active components in plants, such as flavonoids, alkaloids, and terpenoids. In addition, the possibility of increasing the concentration of active substances by bHLH in medicinal plants was assessed. The paper emphasized great significance of model plants and multidisciplinary research fields including modern genomics, transcriptomics, metabolomics and bioinformatics, providing the contribution to improve the discovery and function characterization of bHLH transcription factors. Accelerating the research in the mechanism of bHLH transcription factors on the regulation of active components biosynthesis will promote the development of breeding and variety improvement of Chinese medicinal materials, also ease the pressure of resources exhaustion of traditional Chinese medicine home and abroad.
Alkaloids
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biosynthesis
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Basic Helix-Loop-Helix Transcription Factors
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chemistry
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classification
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genetics
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metabolism
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Flavonoids
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biosynthesis
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Plants, Medicinal
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genetics
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metabolism
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Terpenes
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metabolism
3.Expression of heat-shock transcription factor 1 and X-linked inhibitor of apoptosis protein-associated factor-1 in gastrointestinal cancer.
Ting LI ; Cun-long CHEN ; Ji-de WANG ; Sheng-da CUI ; Dan-yu CUI ; Wen GUO
Journal of Southern Medical University 2008;28(3):487-490
OBJECTIVETo investigate the expressions of X-linked inhibitor of apoptosis protein (XIAP)-associated factor-1 (XAFI) and heat-shock transcription factor 1 (HSF1) and their relationship in human gastrointestinal cancers.
METHODSImmunoblotting was used to analyze the expressions of HSF1 and XAF1 in gastric and colon cancer tissues and in gastrointestinal cancer cells. The gastrointestinal cancer cells were tranfected with a eukaryotic expression vector containing HSF1 gene fragment or subjected to RNA interference to induce up- or down-regulation of HSF1 expression, and the consequence changes in XAF1 expression in the cells was measured. XAF1 expression was also assayed in the cells after stress stimulation for HSF1 expression.
RESULTSThe expression of HSF1 was higher in gastrointestinal cancer tissues than in normal tissues. The expression of XAF1 and HSF1 was inversely correlated in the cancer cell lines, and stress stimuli of the cells up-regulated the expression of HSF1 but down-regulated XAF1 expression.
CONCLUSIONHSF1 expression is increased in gastrointestinal cancer tissues to result in suppressed expression of XAF1, which may be one of the reasons for the low expression of XAF1 in association with the defect of the apoptosis mechanisms in the cancer cells
Cell Line, Tumor ; Colonic Neoplasms ; genetics ; metabolism ; pathology ; DNA-Binding Proteins ; biosynthesis ; genetics ; Heat Shock Transcription Factors ; Humans ; Immunoblotting ; Intracellular Signaling Peptides and Proteins ; Neoplasm Proteins ; biosynthesis ; genetics ; RNA Interference ; Stomach Neoplasms ; genetics ; metabolism ; pathology ; Transcription Factors ; biosynthesis ; genetics ; Transfection
4.Correlation of E2F-1 and Rb expression with papillomatosis and ductal carcinoma in situ of the breast.
Yun NIU ; Yu LI ; Rui-fang NIU ; A-juan LÜ ; Xi-lin FU
Chinese Journal of Oncology 2004;26(5):290-293
OBJECTIVEE2F-1 and Rb are involved in cell cycle regulation. This study was to illustrate the mechanism of transformation from benign papillomatosis to ductal carcinoma in situ (DCIS) of the breast in relation to E2F-1 and Rb expression.
METHODSIn situ hybridization (ISH) was used to determinate the expression of E2F-1 and Rb mRNA of mild papillomatosis (MP, n = 40), severe papillomatosis (SP, n = 40) and DCIS (n = 40). Immunohistochemistry (IHC) was used to examine the expression of E2F-1 and Rb protein.
RESULTSThe positive rate of E2F-1 mRNA expression in MP, SP and DCIS was 17.5%, 45.0% and 80.0%, and that of E2F-1 protein expression was 20.0%, 47.5% and 77.5%, respectively. There were significant differences among the three groups (P < 0.01), and between any two groups (P < 0.01). The positive rate of Rb mRNA expression in MP, SP and DCIS was 90.0%, 50.5% and 20.0%, and that of Rb protein expression was 85.0%, 52.5% and 22.5%, respectively, with statistically significant difference similar with that of E2F-1. With the progression of papillomatosis to DCIS, the expression of E2F-1 mRNA and protein increased, while that of Rb decreased. The protein expression by IHC was positively correlated with the mRNA expression by ISH. However, that of E2F-1 was negatively correlated with Rb.
CONCLUSIONE2F-1 and Rb might provide a valuable basis for screening high risk papillomatosis and new target of gene therapy for pre-cancerous lesions of the breast.
Breast Neoplasms ; genetics ; metabolism ; Carcinoma, Intraductal, Noninfiltrating ; genetics ; metabolism ; Cell Cycle Proteins ; biosynthesis ; genetics ; DNA-Binding Proteins ; biosynthesis ; genetics ; E2F Transcription Factors ; E2F1 Transcription Factor ; Female ; Gene Expression Regulation, Neoplastic ; Genes, Retinoblastoma ; Humans ; Immunohistochemistry ; In Situ Hybridization ; Papilloma ; genetics ; metabolism ; Precancerous Conditions ; genetics ; metabolism ; RNA, Messenger ; biosynthesis ; genetics ; Retinoblastoma Protein ; biosynthesis ; genetics ; Transcription Factors ; biosynthesis ; genetics
5.Expression of the transcription factor PAX5 in childhood acute leukemic cells.
Bei ZHANG ; Li-Jun TIE ; Qi-Dong YE ; Long-Jun GU ; Jing-Yan TANG ; Xiang-Liang YUAN ; Li-Song SHEN
Journal of Experimental Hematology 2006;14(1):6-10
To investigate transcription factor PAX5 expression characteristics in childhood acute leukemic cells, expression levels of PAX5 and CD19 mRNA in 6 hematological tumor cell lines and bone marrow cells of 6 normal children, 58 de novo patients and 4 relapse acute leukemic children, including 39 cases of B-ALL, 10 cases of T-ALL and 13 cases of AML, were detected by a real-time RT-PCR. The results showed that PAX5 and CD19 mRNA expression levels were 2.35% and 2.52% in Namalwa (B-cell lines) respectively, but almost not detectable in other T- and myeloid cell lines. Among clinical samples, expression of PAX5 mRNA in B-ALL was significantly higher than that in T-ALL and AML (P = 0.029 and P = 0.013 respectively). PAX5 expression was significantly lower in T-ALL and AML than that in normal controls. The difference of PAX5 mRNA expression levels between T-ALL and AML was not significant. Individual difference of PAX5 mRNA expression levels in children with B-ALL was great. Moreover, PAX5 mRNA expressions in de novo and relapse patients with B-ALL were significantly higher than those in remission (P = 0.011 and P = 0.006 respectively). As binding sites for B-cell specific activator protein have been identified in the promoter regions of CD19, the study found that in B-ALL, there was clear correlation between the expression levels of PAX5 and CD19, which was also studied by real-time RT-PCR. It is concluded that PAX5 transcripts are readily detectable and quantifiable in clinical materials with B-ALL by real-time RT-PCR. The strong PAX5 mRNA expression in some B-ALL can be considered to be particularly interesting for further analysis.
Adolescent
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Antigens, CD19
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biosynthesis
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genetics
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Cell Line, Tumor
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Child
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Child, Preschool
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Female
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Humans
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Infant
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Male
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PAX5 Transcription Factor
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biosynthesis
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genetics
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Precursor Cell Lymphoblastic Leukemia-Lymphoma
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metabolism
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pathology
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RNA, Messenger
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biosynthesis
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genetics
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Transcription Factors
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biosynthesis
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genetics
6.Improving fatty acid composition and increasing triacylglycerol content in plants by gene engineering: a review.
Han XIA ; Xingjun WANG ; Mengjun LI ; Han XIAO
Chinese Journal of Biotechnology 2010;26(6):735-743
This article reviewed key genes that involved in fatty acid synthesis and triacylglycerol assembly pathway. The transcription factors which play important roles in seed development and oil content were also reviewed. We summarized the achievement in modifying fatty acid composition and increase oil content in plant by gene engineering using these genes.
Fatty Acids
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biosynthesis
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genetics
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Genetic Engineering
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methods
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Plant Oils
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chemistry
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Plants, Genetically Modified
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genetics
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metabolism
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Seeds
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genetics
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metabolism
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Transcription Factors
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genetics
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Triglycerides
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analysis
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biosynthesis
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genetics
7.KLF6mRNA expression in primary hepatocellular carcinoma.
Shaoping, WANG ; Xiaoping, CHEN ; Wanguang, ZHANG ; Fazu, QIU
Journal of Huazhong University of Science and Technology (Medical Sciences) 2004;24(6):585-7
To investigate the expression of KLF6mRNA in primary hepatocellular carcinoma (HCC), nomal liver tissues and the tissues adjacent to the cancers, reverse-transcription polymerase chain reaction (RT-PCR) was employed to investigate the expression of the KLF6 gene in HCC, the corresponding adjacent non-cancerous tissues and normal liver tissue. Our results showed that an amplified fragment of 427 bp DNA was detected in 18 of 19 (94.7%) adjacent non-cancerous tissues and normal liver tissue, and in 12 (85.7%) of 14 HCC. There were no significant differences in the levels of KLF6 mRNA between normal liver and liver tumors (P>0.05). It is concluded that KLF6 mRNA is generally expressed in HCC.
Carcinoma, Hepatocellular/*metabolism
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Kruppel-Like Transcription Factors/*biosynthesis
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Kruppel-Like Transcription Factors/genetics
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Liver/metabolism
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Liver Neoplasms/*metabolism
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Proto-Oncogene Proteins/*biosynthesis
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Proto-Oncogene Proteins/genetics
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RNA, Messenger/biosynthesis
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RNA, Messenger/genetics
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Reverse Transcriptase Polymerase Chain Reaction
8.Construction and structural analysis of integrated cellular network of Corynebacterium glutamicum.
Jinguo JIANG ; Lifu SONG ; Ping ZHENG ; Shiru JIA ; Jibin SUN
Chinese Journal of Biotechnology 2012;28(5):577-591
Corynebacterium glutamicum is one of the most important traditional industrial microorganisms and receiving more and more attention towards a novel cellular factory due to the recently rapid development in genomics and genetic operation toolboxes for Corynebacterium. However, compared to other model organisms such as Escherichia coli, there were few studies on its metabolic regulation, especially a genome-scale integrated cellular network model currently missing for Corynebacterium, which hindered the systematic study of Corynebacterium glutamicum and large-scale rational design and optimization for strains. Here, by gathering relevant information from a number of public databases, we successfully constructed an integrated cellular network, which was composed of 1384 reactions, 1276 metabolites, 88 transcriptional factors and 999 pairs of transcriptional regulatory relationships. The transcriptional regulatory sub-network could be arranged into five layers and the metabolic sub-network presented a clear bow-tie structure. We proposed a new method to extract complex metabolic and regulatory sub-network for product-orientated study taking lysine biosynthesis as an example. The metabolic and regulatory sub-network extracted by our method was more close to the real functional network than the simplex biochemical pathways. The results would be greatly helpful for understanding the high-yielding biomechanism for amino acids and the re-design of the industrial strains.
Corynebacterium glutamicum
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genetics
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metabolism
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Gene Expression Regulation, Bacterial
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Gene Regulatory Networks
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genetics
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Lysine
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biosynthesis
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Metabolic Networks and Pathways
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genetics
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Transcription Factors
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genetics
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Transcription, Genetic
9.Identification and expression analysis of WRKY transcription factors in medicinal plant Catharanthus roseus.
Zhirong YANG ; Xingchun WANG ; Jin'ai XUE ; Lingzhi MENG ; Runzhi LI
Chinese Journal of Biotechnology 2013;29(6):785-802
WRKY transcription factors, one of the largest families of transcriptional regulators in plants, involve in multiple life activities including plant growth and development as well as stress responses. However, little is known about the types and functions of WRKY transcription factors in Catharanthus roseus, an important medicinal plant. In this study, we identified 47 CrWRKY transcriptional factors from 26 009 proteins in Catharanthus roseus, and classified them into three distinct groups (G1, G2 and G3) according to the structure of WRKY domain and evolution of the protein family. The expression profiling showed that these CrWRKY genes expressed in a tissue/organ specific manner. The 47 CrWRKY genes were clustered into three types of expression patterns. The first type includes the CrWRKYs highly expressed in flowers and the protoplast treated with methy jasmonate (MeJA) or yeast extraction (YE). The second type contains the CrWRKYs highly expressed in stem and hairy root. The third type represents the CrWRKYs highly expressed in root, stem, leaf, seedling and the hairy root treated by MeJA. Real time quantitative PCR was employed to further identify the expression patterns of the 16 selected CrWRKY genes in various organs, the MeJA-treated protoplasts and hairy roots of Catharanthus roseus, and similar results were obtained. Notably, the expresion of more than 1/3 CrWRKY genes were regulated by MeJA or YE, indicating that these CrWRKYs are likely involed in the signalling webs which modulate the biosynthesis of terpenoid indole alkaloid and plant responses to various stresses. The present results provide a framework for functional identification of the CrWRKYs and understanding of the regulation network of terpenoid indole alkaloid biosynthesis in Catharanthus roseus.
Amino Acid Sequence
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Catharanthus
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genetics
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metabolism
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Gene Expression Regulation, Plant
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Genes, Plant
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Molecular Sequence Data
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Plant Proteins
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biosynthesis
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genetics
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Plants, Medicinal
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genetics
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metabolism
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Transcription Factors
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biosynthesis
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genetics
10.Preparation, purification and identification of the polyclonal antibody of PHD finger protein 8.
Chinese Journal of Biotechnology 2010;26(3):393-397
PHD finger protein 8 (PHF8) is a novel protein with PHD domain and Jmjc domain, which may play important role in regulating transcription and histone demethylation. It is necessary to generate the antibody against PHF8 in order to further study its biological function. First we constructed plasmid pET41b-PHF8 (aa886-936) and expressed the GST-PHF8 (aa886-936) fusion protein in Escherichia coli BL21. We then purified the fusion protein by Glutathione Sepharose 4B beads and subjected to immunize the rabbits for acquiring antiserum. We obtained PHF8 polyclonal antibody by affinity purifying the antiserum with CNBr-activated Sepharose 4B beads. The antibody was effective in Western blotting and immunofluorescence with high specificity. Immunofluorescence also showed that PHF8 protein was located in nucleus in HeLa cells.
Animals
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Antibodies
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isolation & purification
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Escherichia coli
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genetics
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metabolism
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Female
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Genetic Vectors
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genetics
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Glutathione Transferase
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biosynthesis
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genetics
;
immunology
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Histone Demethylases
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biosynthesis
;
genetics
;
immunology
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Immunization
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Rabbits
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Recombinant Fusion Proteins
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biosynthesis
;
genetics
;
immunology
;
Transcription Factors
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biosynthesis
;
genetics
;
immunology