Overexpression of chicken Klf2 promotes klf7 transcription and inhibits adipocyte differentiation / 生物工程学报

Overexpression of Krüppel like factor 2 (Klf2) or Klf7 inhibits adipocyte formation. However, it remains unclear whether Klf2 regulates klf7 expression in adipose tissue. In this study, oil red O staining and Western blotting were employed to study the effect of Klf2 overexpression on the differentiation of chicken preadipocytes. The results showed that Klf2 overexpression inhibited the differentiation of chicken preadipocytes induced by oleate and the expression of pparγ, while promoted klf7 expression in chicken preadipocytes. Spearman correlation analysis was used to study the correlation between the expression data of klf2 and klf7 in the adipose tissue of both human and chicken. The results showed that there was a significantly positive correlation between the expression of klf2 and klf7 in adipose tissues (r > 0.1). Luciferase reporter assay showed that overexpression of Klf2 significantly promoted the activity of chicken klf7 promoter (-241/-91, -521/-91, -1 845/-91, -2 286/-91, -1 215/-91; P < 0.05). In addition, the activity of klf7 promoter (-241/-91) reporter in chicken preadipocytes was significantly positively correlated with the amount of klf2 overexpression plasmid transfected (Tau=0.917 66, P=1.074×10-7). Moreover, Klf2 overexpression significantly promoted the mRNA expression of klf7 in chicken preadipocytes (P < 0.05). In conclusion, upregulation of klf7 expression might be one of the pathways that Klf2 inhibits chicken adipocyte differentiation, and the sequence from -241 bp to -91 bp upstream chicken klf7 translation start site might mediate the regulation of Klf2 on klf7 transcription.

Comparison of the Promoter Activity of vip3A and cry1Ia using IeGFP as a Fluorescent Reporter / 中国生物化学与分子生物学报

In spite of no homology in sequences‚ Vip3A and Cry1Ia toxins of Bacillus thuringiensis (Bt) share common characteristics‚ such as translocation across cell membranes after synthesis at the early stage of sporulation. The aim of the present study was to compare the regulation patterns and activities of the promoters of vip3A (P

Activity and transcriptional regulatory elements of the promoter in Arctic fox (Vulpes lagopus) β-defensin103 gene / 生物工程学报

The aim of this study was to screen the active regions and transcription factor binding sites in the promoter of the CBD103 gene related to Arctic fox coat color, and to provide a basis for revealing the molecular genetic mechanism of CBD103 gene regulating the coat color formation. The 5'-flanking region fragment 2 123 bp of Arctic fox CBD103 gene was cloned, and 4 truncated promoter reporter vectors of different lengths were constructed. The promoter activity was detected by the dual-luciferase reporter assay system. Point mutations were performed on the 3 predicted specificity protein 1 (Sp1) transcription factor binding sites in the highest promoter active region, and 3 mutant vectors were constructed. The activity was then detected by the dual-luciferase reporter assay system. The results showed that the region 1 656 (-1 604/+51) had the highest activity in the 4 truncated promoters of different lengths, and the promoter activity of the three mutant vectors constructed in this region were significantly lower than that of the wild type (fragment 1 656). The region of -1 604 /+51 was the core promoter region of CBD103 gene in Arctic fox and -1 552/-1 564, -1 439/-1 454 and -329/-339 regions were positive regulatory regions. This study successfully obtained the core promoter region and positive regulation regions of the Arctic fox CBD103 gene, which laid a foundation for further study on the molecular genetic mechanism of this gene regulating Arctic fox coat color.

Role of the CHD7 chromatin remodeler protein in glioblastoma multiformePalavras-chave em inglês Cell motility / Papel do remodelador de cromatina CHD7 em glioblastoma multiforme

Chromatin remodeler proteins exert an important function in promoting dynamic modifications in the chromatin architecture, rendering the transcriptional machinery available to the condensed genomic DNA. Due to this central role in regulating gene transcription, deregulation of these molecular machines may lead to severe perturbations in the normal cell functions. Loss-of-function mutations in the CHD7 gene, a member of the chromodomain helicase DNA-binding (CHD) family, are the major cause of the CHARGE syndrome in humans. The disease is characterized by a variety of congenital anomalies, including malformations of the craniofacial structures, peripheral nervous system, ears, eyes and heart. In this context, several studies have already shown the importance of CHD7 for proper function of the neural stem cells (NSCs). Interestingly, we found that CHD7 mRNA levels are upregulated in gliomas, when compared to normal brain tissue, therefore, we hypothesized that CHD7 might have a role in the pathogenesis of these tumors. To investigate the possible oncogenic role of CHD7 in glioblastoma (GBM), we adopted gain- and loss-of-function approaches in adherent GBM cell lines. Using CRISPR_Cas9 genome editing, we found that CHD7 deletion suppresses anchorage-independent growth and reduces spheroid invasion in human LN-229 cells. Moreover, deletion of CHD7 delayed tumor growth and improved overall survival in an orthotopic xenograft glioma mouse model. Conversely, ectopic overexpression of CHD7 in LN-428 and A172 cells was found to increase cell motility and invasiveness in vitro and LN-428 tumor growth in vivo. RNAseq analysis showed that alterations of CHD7 expression levels promote changes in several molecular pathways and modulate critical genes associated with cell adhesion and locomotion. However, the mechanisms underlying the effects of CHD7 overexpression in glioma tissue are still not understood. Here, we also generated recombinant plasmid with functional CHD7 promoter activity reported by luciferase assay. This powerful tool should enable future studies to determine the direct targeting relationship between different signal transduction pathways and CHD7 geneexpression. In summary, our findings indicate that GBM cells expressing a high level of CHD7 may exist and contribute to tumor infiltration and recurrence. Further studies should warrant important clinical-translational implications of our findings for GBM treatment

As proteínas remodeladoras de cromatina exercem importante papel, promovendo modificações dinâmicas na arquitetura da cromatina e dando acesso à maquinaria transcricional ao DNA genômico condensado. Devido à esta função central na regulação da transcrição gênica, a desregulação dessas máquinas moleculares pode levar a perturbações graves na função normal das células. Assim, por exemplo, mutações do tipo perda de função no gene CHD7, um membro da família "chromodomain helicase DNA-binding" (CHD), são a principal causa da síndrome de CHARGE em humanos. A doença é caracterizada por uma variedade de anomalias congênitas, incluindo malformações das estruturas craniofaciais, sistema nervoso periférico, orelhas, olhos e coração. Neste contexto, vários estudos já mostraram a importância da proteína CHD7 para o funcionamento normal de células-tronco neurais (NSCs). Curiosamente, descobrimos que os níveis de mRNA de CHD7 estão mais fortemente expressos em gliomas, quando comparados ao tecido cerebral normal, portanto, nós hipotetizamos que CHD7 poderia ter um papel na patogênese desses tumores. Para investigar o possível papel oncogênico de CHD7 em glioblastoma (GBM), utilizamos enfoques de ganho e perda de função em linhagens celulares aderentes de GBM. Utilizando a técnica de CRISPR_Cas9 para edição do genoma, demonstramos que a deleção do gene CHD7 suprime o crescimento independente de ancoragem e reduz a invasão de esferóides em células LN-229 humanas de GBM. Além disso, a deleção de CHD7 reduziu o crescimento do tumor e melhorou a sobrevida em modelo de injeção ortotópica xenográfica em camundongo. Por outro lado, verificou-se que a super-expressão ectópica de CHD7 nas células LN-428 e A172 aumenta não só a motilidade celular e a capacidade de invasão in vitro, mas, também, o crescimento do tumor de LN-428 in vivo. A análise de RNA-seq mostrou que o nocauteamento da sequência codificadora de CHD7 e sua super-expressão promovem alterações em diversas vias moleculares, modulando genes críticosassociados à adesão e locomoção celular. No entanto, os mecanismos subjacentes aos efeitos da super-expressão de CHD7 em tecidos de glioma ainda não são compreendidos. Neste trabalho, geramos um plasmídeo recombinante contendo um fragmento da região promotora de CHD7, o qual se mostrou funcional em ensaios de luciferase. Esta ferramenta permitirá que estudos futuros possam identificar a relação direta entre as diferentes vias de transdução de sinal e a expressão do gene CHD7. Em resumo, nossos achados indicam que células de GBM expressando um alto nível de CHD7 podem existir e contribuir para a infiltração e recorrência do tumor. Estudos posteriores deverão avaliar as possíveis implicações dos resultados apresentados neste trabalho para a translação clínica no tratamento de pacientes com GBM

KSHV RTA upregulates expression of survivin through interacting with GC/Sp1 and p53 cis-acting elements / 中国病理生理杂志

AIM: To identify the potential elements within the survivin promoter indispensable for the upregu-lation of survivin by Kaposi’ s sarcoma-associated herpesvirus encoded replication and transcription activator ( KSHV RTA).METHODS: A series of truncated survivin promoter luciferase constructs were generated.Reporter assay and chromatin immunoprecipitation were performed to detect the interaction between RTA and the important cis-acting elements. RESULTS: Deletion of the GC/Sp1 and p53 binding sites within the survivin promoter almost completely shut down the survivin promoter activity and the p53 cis-acting element synergistically contributes to survivin promoter activation by RTA. CONCLUSION: KSHV RTA interacts with the GC/Sp1 and p53 cis-acting elements and regulates the expression of cellu-lar survivin by specifically increasing the activity of survivin promoter.

Phosphorylation of DegU is essential for activation of amyE expression in Bacillus subtilis.

Alpha (α)-amylase (amyE) is one of the major exo-enzymes secreted by Bacillus subtilis during the post-exponential phase. The DegS-DegU two-component system regulates expression of majority of post-exponentially expressed genes in B. subtilis. It has been demonstrated that varying levels of the phosphorylated form of DegU (DegU-P) control different cellular processes. Exo-protease production is observed when effective concentration of DegU-P rises in the cell, whereas swarming motility is favoured at very low amounts of DegU-P. In this study we show that like other exo-proteases, expression of amyE is positively regulated by increase in DegU-P levels in the cell. We also demonstrate that residues at the DNA-binding helix-turn-helix (HTH) motif of DegU are necessary for the amyE expression. This observation is further reinforced by demonstrating the direct interaction of DegU on amyE promoter.

Characterization of immediate early gene ORF62 of live attenuated varicella vaccine Oka strains pro-duced in China / 中华微生物学和免疫学杂志

Objective To investigate mutations in immediate early ( IE) gene ORF62 of three var-icella vaccine Oka strains ( vOka ) including two strains produced in China and their parental Oka strain (pOka), and then to further elucidate its possible roles in attenuation mechanism by comparing their ORF 62 promoter sequences and its activities , ORF62 coding regions and its transactivities .Methods ORF62 pro-moter-reporter plasmids and ORF62-expressing plasmids of pOka and three vOka strains ( vOka-BK from Changchun BCHT Biotechnology Co ., vOka-SH from Shanghai Institute of Biological Product Co .Ltd., and vOka-GSK from GlaxoSmithKline plc, as control) were constructed, respectively.ORF62 promoter regions and coding regions of the four strains were sequenced and then compared with each other .Differences of ac-tivities of the ORF62 promoter, and transactivities of the ORF62-encoded IE62 upon immediate early (ORF4), early (ORF28) and late (ORF67) gene promoters between pOka and vOka strains were assayed with transient transfection technique .Results Compared with pOka strain , three vOka strains had a con-sistent T deletion mutation at site 110 050 in ORF62 promoters, which did not result in any change of tran-scription factor binding motif .However , activities of ORF62 promoters from three vOka strains were signifi-cantly lower than those of pOka strain .Three consistent substitution mutations were observed in ORF 62 cod-ing regions of three vOka strains and three new enzyme restriction sites including SmaⅠ, NaeⅠand BssHⅡwere generated, respectively.Transactivities of IE62 from three vOka strains upon ORF4, ORF28 and ORF67 promoters were significantly higher than those of pOka both in CV-1 and MeWo cells , except that vOka-SH IE62 showed significantly lower transactivities upon ORF 4 promoter than those of pOka strain in CV-1 cells.Conclusion Consistent T deletion mutation at site 110 050 in ORF62 promoters of three vOka strains might be responsible for the reduced promoter activities and the changes of IE 62 transactivities .How-ever , it seemed that cell types have no significant effect on ORF 62 promoter activity or IE 62 transactivity be-tween pOka and vOka strains .

Cloning of Alpha gene segments from t(6;11) translocation renal cell carcinoma and analysis of their promoter activities / 中国肿瘤临床

To construct recombinant reporter plasmids containing different Alpha gene segments and Alpha1-TFEB fusion gene and to evaluate the promoter activity of the Alpha gene. Methods:Promoter regions of the Alpha gene were predicted using a software Primer 0.5. Five Alpha gene segments with different lengths and a normal TFEB gene promoter (pTFEB) were amplified via polymerase chain reaction, and recombinant reporter plasmids containing different Alpha gene segments and a normal TFEB gene pro-moter were constructed. Liposome transfection was used to transfect these vectors into the human embryo kidney 293T cells. The pro-moter activity of the Alpha gene was evaluated via luciferase assay. Meanwhile, the recombinant Alpha1-TFEB plasmid was construct-ed and transfected into the 293T cells. The TFEB expression of the recombinant Alpha1-TFEB plasmid was then detected via Western blot. Results: Recombinant reporter plasmids containing different Alpha gene segments and pTFEB were constructed successfully. Compared with the luciferase activity of pGL3-Basic, that of the groups with Alpha1, Alpha2, Alpha3, Alpha4 and Alpha5 significantly increased (P<0.01). The luciferase activity also increased significantly in the groups with Alpha1, Alpha2 and Alpha5 compared with that of the pTFEB group (P<0.01). The TFEB expression of the pGL3-Enhancer-Alpha1-TFEB was significantly higher compared with that of the pGL3-Enhancer group. Conclusion:In t(6;11) translocation RCC, the Alpha gene has a strong promoter activity and it en-hances TFEB expression. The strongest promoter activity region is in Alpha5 with a sequence from 643 bp to 693 bp.

Construction of series reporter plasmids with truncated and deleted human telomerase reverse transcriptase promoter / 中华微生物学和免疫学杂志

Objective To construct series of reporter plasmids with truncated and deleted hTERT promoter.Methods Gene fragments of hTERT promoter was amplified by PCR and cloned into pGL3-Basic to construct luciferase reporter vectors.Dual luciferase assays were performed with cell lysates of HepG2 and COS-7 cells cotransfected with hTERT promoter reporter plasmids and pRL-TK.Results Series of luciferase reporter plasmids with truncated and deleted hTERT promoter were successfully constructed and respectively named pGL3B-895,pGL3B-371,pGL3B-DELS2,pGL3B-349,pGL3B-329,pGL3B-318,pGL3B-306.Dual luciferase reporter assays showed that all the reporter vectors have promoter activity both in HepG2 and COS-7.Conclusion Series of luciferase reporter plasmids with truncated and deleted hTERT promoter were successfully constructed,and their promoter activity were verified.These plasmids provide necessary experimental naterials for further investigation of regulation of hTERT during hepatocarcinoma development.

Transcription factors regulate Forkhead box O1 gene promoter activity in pancreatic β-cells.

Background: Transcription factors of the Forkhead box O (Fox O) family have important roles in cellular proliferation, apoptosis, differentiation, and stress resistance. In pancreatic ?-cells, FoxO1 protein plays an important role in ?-cells development. The molecular mechanism of transcriptional regulation of basal FoxO1 gene expression in pancreatic ?-cells is not fully understood. Objectives: Explore the potential transcription factors regulating FoxO1 promoter activity using pancreatic ?-cell line (RINm5F cells) Methods: Promoter screening method, luciferase reporter gene analysis, transient expression assay system, and deletion analysis of a -974/-18 bp 5’ upstream region of the mouse FoxO1 gene were used in this study. Results: An inhibition domain (-974/-321) and an activation domain (-321/-18) was identified through deletion analysis of a -974/-18 bp 5’ upstream region of the mouse FoxO1 gene. Using the promoter screening method, several transcription factors were selected. Luciferase reporter studies showed that these factors could regulate FoxO1 promoter activity in RINm5F cells. Among these factors, cAMP response-element binding protein (CREB) could positively regulate FoxO1 promoter activity. Signal transducer and activator of transcription 1 (STAT1) played a negative role on FoxO1 promoter. In addition, ETS oncogene family member Elk-1 did not affect the FoxO1 promoter activity. Conclusion: Two transcription factors (CREB and STAT1) could effectively regulate the mouse FoxO1 gene promoter activity.

HIV-1 Tat down-regulates expression of mitotic centromere-associated kinesin through inhibiting promoter activity / 第二军医大学学报

Objective: To investigate the regulatory effect of HIV-1 Tat on mitotic centromere-associated kinesin (MCAK) expression and the related mechanism. Methods: Tat-expression TE671 cell model and purified prokaryotically expressed Tat protein were used to verify the down-regulated expression of MCAK using Northern blotting and Western blotting analysis. Various DNA fragments in the promoter region of the MCAK gene were amplified with PCR, linked to the luciferase reporter plasmid, and then transferred into TE671 cells. Luciferase activity analysis was performed to measure the promoter activity of various DNA fragments, so as to determine the active promoter region of MCAK gene. Moreover, HIV-1 Tat protein was co-incubated with TE671 cells, and the promoter activity was detected to analyze the modulating effect of Tat on promoter activity in vitro. Results: The results of Northern blotting and Western blotting analysis indicated that the mRNA and protein levels of MCAK were strongly decreased by Tat protein. The core region of MCAK promoter was located in -399∼+1 bp region, and the promoter activity was strikingly inhibited by Tat protein. Conclusion HIV-1 Tat has a marked inhibitory effect on MCAK expression, which might be related to the decreased promoter activity caused by Tat protein.

Construction of human Egr-1 promoter and its response to ionizing radiation in tumor cells / 细胞与分子免疫学杂志

AIM: To construct human Egr-1 promoter luciferase reporter system and study its activity induced by i-onizing radiation. METHODS: Egr-1 promoter was obtained by human genomic PCR and cloned into pGL3-basic vector. After transfection of recombinant plasmid into human tumor cells, the Egr-1 promoter activity induced by ionizing radiation was detected by luciferase reporter assay. RESULTS: The luciferasy reporter system of Egr-1 promoter was successfully constructed. The activity of Egr-1 promoter was substantially increased after different doses of IR and reached to the peak at the time point of 48h after IR. CONCLUSION: The Egr-1 promoter was constructed in this study showed IR inducible activity in tumor cells, laying foundation for the research of radiation, mediated gene therapy.

5-Fu activates NKG2D ligands MICA/B promoter in transiently transfected A549 cell line / 军事医学科学院院刊

Objective:To analyze the activities of human NKG2D ligand MICA/B promoter induced by 5-Fu.Methods:The 5'-end flanking regions of MICA /B promoter and their different truncated fragments were amplified from A549 genome by PCR. The resulting amplicons were cloned into pGL3-Basic vector to generate the MICA/B luciferase reporter plasmids. All the constructs were transiently transfected A549 cells. The promoter region activities were determined by dual-luciferase reporter assays. The effect of 5-Fu on the promoter activities of MICA/B was also tested.Results and Conclusion:The 5'-end flanking regions of MICA /B promoter and five of their different truncated fragments were successfully obtained. The normalized luciferase reporter gene activities driven by the above promoters and fragments were 3.61,2.26,1.63,0.313,0.711 and 0.663 for MICA and 17.49,10.11,7.398,0.822,0.997 and 0.49 for MICB,respectively. Promoter activities in transiently transfected A549 cells treated by 20,40,80,160 and 320 μg/m of 5-Fu increased 1.69,1.48,1.62,1.55 and 1.78 fold for MICA and 1.44,1.87,1.38,1.19 and 1.25 fold for MICB. Our results suggest that 5-FU can significantly up-regulate the promoter activity of both MICA and MICB.

Isolation and Identification of Promoter Sequence of Interferon Regulatory Factor-3 and Detection of Its Promotor Activity in Human Embryonic Kidney-293 Cells / 实用儿科临床杂志

Objective To construct a luciferase reporter plasmid containing interferon regulatory factor 3(IRF-3)human gene promoter and to evaluate promoter activity in human embryonic kidney(HEK)-293 cells.Methods The 1 000 bp fragment was amplified by PCR with human genomic DNA as a template and was directionally cloned into pGL3-basic multiple cloning sites to construct the luciferase repor-ter plasmid pGL3-pIRF-3.Transfection of HEK-293 cells with the promoter-driven lucife-rase construct was performed to induce lucife-rase gene expression and calculate the relative luciferase activity unit(RLU).Promoter sequence of 1 000 bp upstream of transcription initiation site of IRF-3 was analyzed by using Promoter 2.0 Prediction software.Results DNA sequencing and restriction endonuclease analysis verified the successful construction of the plasmid pGL3-pIRF-3.This IRF-3 promoter exhibited a strong promoter activity with an increase of 42.2-fold of RLU in HEK-293 cells when compared with pGL-3 basic vector.The transfection experiment confirmed that the levels of its activation were significantly higher than that in controls in HEK-293 cells.Function analysis of IRF-3 promoter disclosed seve-ral GATA-1 and specific protein 1(Sp1) sites and E2F in minimal promoter region.Conclusion The plasmid pGL3-pIRF-3 promoter is successfully constructed and has a strong basal promoter activity in HEK-293 cells.

Cloning of Human PRL-3 Gene Promoter and Preliminary Identification of Its Snail Binding Site / 生物化学与生物物理进展

PRL-3 is a key gene related to metastasis of colorectal carcinoma. However, it is known little about the possible regulatory mechanisms of PRL-3 gene expression. There were three possible promoter regions predicted by TRED, a promoter prediction software,which were all located in the upstream regions of PRL-3 gene. One of PRL-3 gene candidate promoters was located in the region of about -1kb upstream proximal to 5′ UTR of PRL-3 gene. Many possible transcription factor binding sites such as Snail, n-MYC, ARNT, E74A, NF-kappaB, NRF-2 and AML-1 were predicted in the region by Consite, a promoter analysis web system. Interestingly, a 5′ CACCTG 3′ core sequence and other related sequences of snail binding sites were found in promoter region of PRL-3 genes. Two PRL-3 gene promoters between -699 to 299 nt and between -642 to -383 nt were cloned into pGL3 vector with luciferase report gene. Both of them had promoter activities in four different cell lines including colorectal carcinoma cell lines SW480 and SW620, nasopharyngeal carcinoma cell line CNE2 and human embryo kidney cell line 293A. Interestingly, the luciferase activities of the short DNA fragmentations with Snail binding site′s core sequence 5′ CACCTG 3′ were higher than that of the longer one. PRL-3 promoter obtaining the 5′ CACCTG 3′ core sequence of Snail binding sites, was validated to bind to snail by chromatin immunoprecipitation (CHIP) analysis and electrophoretic mobility shift assay (EMSA) in SW480 cells. The data suggested that Snail was involved in regulation of PRL-3.

Influence of the sequence variations of the HLA-DR promoters derived from human melanoma cell lines on nuclear protein binding and promoter activity

In previous studies we reported that the expression of HLA-DR on melanoma cell lines was differentially modulated by IFN- gamma and that the transcription rate was responsible for this differential modulation. We have also reported the nucleotide sequence variations in the promoter region of HLA-DR genes, and proposed that differences in the promoter activity by the sequence variations of the HLA-DR promoters might contribute to such a differential transcriptional regulation at the promoter level. In this study, in order to assess whether the sequence variations of the HLA-DR promoters affect the factor binding and exert influence on the promoter activity, nuclear factor binding to our previous six HLA-DRA and fourteen HLA-DRB promoter clones was evaluated with the nuclear protein extracted from a B-lymphoblastoid cell line (BLCL), BH, together with the chloramphenicol acetyltransferase (CAT) reporter assay. In the HLA-DRA promoters, clone 35 containing one bp nucleotide sequence variation at the octamer binding site (OCT) (GATTTGC to GATCTGC) showed relatively weak factor binding. In the HLA-DRB promoters, clusters I, III, and IV of our previous HLA-DRB promoter homologues, containing one bp nucleotide sequence variation (GATTCG) in their Y boxes exhibited weak factor binding and CAT activity compared to other clusters (GATTGG) that showed strong factor binding and CAT activity. This data suggests chat the binding patterns of transcription factors influenced by the nucleotide sequence variations of the HLA-DR promoter could affect the promoter activity and the DNA sequence elements in the HLA-DR promoter could mediate transcriptional regulation.

The Effect of Interferon-γ and Tumor Necrosis Factor-α on COL1A2 Promoter Activity Elevated by Interleukin-4 in Human Skin Fibroblasts Cultures

BACKGROUND: IL-4 is known as a potent stimulating factor and, TNF-α and IFN-γ suppress collagen synthesis of dermal fibroblasts. However, relatively little is known about interaction of these cytokines. OBJECTIVE: The purpose of this study was to evaluate the interactional effect of TNF-α and INF-r for the type I collagen gene expression and promoter activation produced by IL-4. METHODS: Using dermal fibroblasts from the normal skin cultured with three cytokines, IL-4, TNF-α and IFN-γ, we examined Northern blot analysis with each cDNA and assayed CAT activity with human pro a 2(l)collagen(COL1A2)/CAT reporter gene chimeric construct. RESULTS: Compared to the control, treating with IL-4 resulted in prominent elevation of both type I procollagen mRNA levels and prce 2(I) collagen promoter activity. IL-4 with TNF-α suppressed the IL-4 induced elevations, whereas IL-4 with IFN-γ did not reveal the obvious suppression of the elevations produced by IL-4. Fibroolasts treated with IL-4 together with IFN-γ and TNF-α completely abolished the type I procollagen gene expression and the activation of COL1A2 promoter gene elicited by IL-4. CONCLUSION: IL-4 induced enhancement of type I collagen gene expression was synergistically suppressed by TNF-α and IFN-γ on transcriptional level.