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 ; biosynthesis ; Basic Helix-Loop-Helix Transcription Factors ; chemistry ; classification ; genetics ; metabolism ; Flavonoids ; biosynthesis ; Plants, Medicinal ; genetics ; metabolism ; Terpenes ; metabolism

The purpose of this study was to investigate the effect on the expression of NF-kappaBp65 of osteoblast-like cell under stretch load with the same amplitude but different daily loading times. The osteoblast-like cells MG-63 were passage cultured and stretched by the four-point-bend loading device; based on the daily loading times, the osteoblast-like cells were randomly divided into four groups. The first was the control, the others were stretched with mechanical tension with the same amplitude of 2,000 mu strain and at the same frequency of 0.5 Hz., but the daily loading times were 1 time/d, 2 times/d, 4 times/d differently for each group, the periods of mechanical tension applied to the cells of the three groups were all 60 min/d and lasted for 2d total. After the cells being streteched, the expression levels of NF-kappaBp65 of the osteoblast-like cells of the three groups and control group were investigated by using the techniques of immunohistochemistry, and were compared with each other. The results showed that the positive expression ratios of the four groups were different significantly; the positive expression ratio of the control was lower than those of the other three groups; the positive expression ratio of the 4 times/d group was higher than those of the other two stretched groups; the positive expression ratio of the 2 times/d group was higher than that of the 1 time/d group. The results suggested that when the osteoblast-like cell was under the stretch load with different daily loading times but the same amplitude, the expression ratio of NF-kappaBp65 in the cell increased with the rising of the stimulating times. It means that the mechanical strain with high daily loading times could promote the transcriptional level of osteoblast-like cell more effectively.
Cell Line ; Humans ; Mechanotransduction, Cellular ; Osteoblasts ; cytology ; metabolism ; Stress, Mechanical ; Time Factors ; Transcription Factor RelA ; biosynthesis

Animals ; Gene Expression ; Humans ; Induced Pluripotent Stem Cells ; metabolism ; physiology ; Mice ; Transcription Factors ; biosynthesis

OBJECTIVETo explore the patterns of Cx43 and Pax3 protein expressions in the small intestinal muscular layers of human embryo during early development.

METHODSImmunohistochemistry with SABC method was employed to examine the expression of Cx43 and Pax3 proteins in the muscular layers of the small intestine in early human embryos in the second to fourth months of gestation.

RESULTSIn the second month of gestation, the muscle layer of the small intestine was negative for Cx43 and Pax3 protein expressions. In the third month, Cx43 and Pax3 expressions were negative in the inner circular muscle layer, but some positive cells were found in the longitudinal muscle layer and the myenteric plexus. In the fourth month, positive expression of Cx43 and Pax3 proteins were seen in the entire muscle layer.

CONCLUSIONCx43 and Pax3 proteins are closely related to the growth and development of the cells and tissues in the small intestinal muscle layer in human embryos.

Connexin 43 ; biosynthesis ; Embryo, Mammalian ; metabolism ; Humans ; Immunohistochemistry ; Intestine, Small ; embryology ; metabolism ; Muscle, Smooth ; embryology ; metabolism ; PAX3 Transcription Factor ; Paired Box Transcription Factors ; biosynthesis

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 ; Antigens, CD19 ; biosynthesis ; genetics ; Cell Line, Tumor ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Male ; PAX5 Transcription Factor ; biosynthesis ; genetics ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; metabolism ; pathology ; RNA, Messenger ; biosynthesis ; genetics ; Transcription Factors ; biosynthesis ; genetics

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 ; Kruppel-Like Transcription Factors/*biosynthesis ; Kruppel-Like Transcription Factors/genetics ; Liver/metabolism ; Liver Neoplasms/*metabolism ; Proto-Oncogene Proteins/*biosynthesis ; Proto-Oncogene Proteins/genetics ; RNA, Messenger/biosynthesis ; RNA, Messenger/genetics ; Reverse Transcriptase Polymerase Chain Reaction

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

The human basic Krüppel-like factor (hBKLF) is a newly cloned human transcription factor from the cDNA library of fetal liver. It belongs to the Krüppel-like transcription factor family. Previous expression study showed that it is a hematopoietic related factor. This study was aimed to investigate the effect of hBKLF on cell proliferation, differentiation and hemoglobin synthesis by using K562 cell line as model. The sense and antisense expression plasmids of hBKLF were constructed, and transfected into K562 cells by lipofectamine. After G418 selection for 4 weeks, the cell line with stable expression of the gene was obtained. Then the hBKLF expression level, proliferation ability, colony formation and hemoglobin production were detected by RT-PCR and Western blot, MTT method, methyl cellulose semisolid culture method and benzidine test respectively. The morphologic change of cell was observed with inverted microscope. The results showed that the sense plasmid could increase hBKLF level and antisense plasmid could decrease hBKLF expression. When hBKLF level was down-regulated, K562 cells could proliferate more quickly and synthesize more hemoglobin. But there were no differences in colony formation ability and no apparent morphologic change. It is concluded that hBKLF can inhibit hematopoietic cell proliferation and hemoglobin synthesis. It is suggested that hBKLF plays an important role in the proliferation and differentiation of hematopoietic cells.
Animals ; COS Cells ; Cell Differentiation ; physiology ; Cell Proliferation ; drug effects ; Cell Transformation, Neoplastic ; drug effects ; Cercopithecus aethiops ; Hemoglobins ; biosynthesis ; Humans ; K562 Cells ; Kruppel-Like Transcription Factors ; biosynthesis ; genetics ; pharmacology ; Transcription Factors ; biosynthesis ; genetics ; Transfection

OBJECTIVETo investigate the expression of gene BRG1 in prostatic intraepithelial neoplasia and adenocarcinoma, and the relationship between gene BRG1 expression and the clinicopathological features of prostate carcinoma.

METHODSGene BRG1 expression was evaluated in 37 cases of human prostate carcinoma, 13 human prostatic intraepithelial neoplasia (PIN) and 14 human benign prostatic hyperplasia (BPH) by using immunohistochemistry (EnVision method) and tissue microarray.

RESULTSThe positive rates of BRG1 protein were 81.08% (30/37), 38.46% (5/13) and 14.28% (2/14) in prostate carcinoma, PIN and BPH, respectively, significantly higher in the first group than in the latter two (P < 0.05). There was no statistically significant difference in BRG1 gene expression either between PIN and BPH (P > 0.05) or between the groups of the moderate differentiation (the Gleason histologic grading: 5-7) and the lower one (the Gleason histologic grading: 8-10) (P > 0.05).

CONCLUSIONBRG1 may play an important role in the development of prostate carcinoma. Tissue microarray technology, with the advantages of high throughput, conciseness, rapidity, high efficiency, low cost, and nice reproducibility, has significant practical value and broad application prospects in pathology.

Aged ; Aged, 80 and over ; DNA Helicases ; biosynthesis ; Humans ; Immunohistochemistry ; Male ; Microchip Analytical Procedures ; Middle Aged ; Nuclear Proteins ; biosynthesis ; Prostatic Neoplasms ; metabolism ; pathology ; Reproducibility of Results ; Transcription Factors ; biosynthesis

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 ; biosynthesis ; genetics ; isolation & purification ; Escherichia coli ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; Streptococcus pneumoniae ; genetics ; metabolism ; Transcription Factors ; biosynthesis ; genetics ; isolation & purification