scholarly journals Regulation of human prohormone convertase 2 promoter activity by the transcription factor EGR-1

1997 ◽  
Vol 328 (1) ◽  
pp. 69-74 ◽  
Author(s):  
Erik JANSEN ◽  
A. Y. Torik AYOUBI ◽  
M. P. Sandra MEULEMANS ◽  
Wim J. M. VAN DE VEN
Keyword(s):  
Transcription Factor ◽  
Promoter Region ◽  
Promoter Activity ◽  
Secretory Pathway ◽  
Tata Box ◽  
Proximal Promoter ◽  
Prohormone Convertase ◽  
Specific Expression ◽  
Proximal Promoter Region ◽  
Prohormone Convertase 2

Prohormone convertases are involved in the tissue-specific endoproteolytic processing of prohormones and neuropeptide precursors within the secretory pathway. In the present study, we have isolated genomic clones comprising the 5ʹ-terminal region of the human prohormone convertase 2 (PC2) gene and established characteristics of the PC2 promoter region. The proximal promoter region is very G+C-rich and does not contain a canonical TATA box or a CAAT box. Transient expression assays with a set of human PC2 gene fragments containing progressive 5ʹ deletions demonstrate that the proximal promoter region is capable of directing high levels of neuroendocrine-specific expression of reporter gene constructs. In addition, we show that the transcription factor EGR-1 interacts with two distinct elements within the proximal human PC2 promoter region. Transfection experiments also demonstrate that EGR-1 is able to enhance PC2 promoter activity.

Kidney-specific expression of human organic cation transporter 2 (OCT2/SLC22A2) is regulated by DNA methylation

2008 ◽  
Vol 295 (1) ◽  
pp. F165-F170 ◽  
Author(s):  
Masayo Aoki ◽  
Tomohiro Terada ◽  
Moto Kajiwara ◽  
Ken Ogasawara ◽  
Iwao Ikai ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Promoter Region ◽  
Organic Cation ◽  
Methylation Status ◽  
Organic Cation Transporter ◽  
Proximal Promoter ◽  
Specific Expression ◽  
Proximal Promoter Region ◽  
E Box ◽  
Organic Cation Transporter 2

Human organic cation transporter 2 (OCT2/SLC22A2), which is specifically expressed in the kidney, plays critical roles in the renal secretion of cationic compounds. Tissue expression and membrane localization of OCT2 are closely related to the tissue distribution, pharmacological effects, and/or adverse effects of its substrate drugs. However, the molecular mechanisms underlying the kidney-specific expression of OCT2 have not been elucidated. In the present study, therefore, we examined the contribution of DNA methylation of the promoter region for the OCT2 gene to its tissue-specific expression using human tissue samples. In vivo methylation status of the proximal promoter region of OCT2 and that of OCT1, a liver-specific organic cation transporter, were investigated by bisulfite sequencing using human genomic DNA extracted from the kidney and liver. All CpG sites in the OCT2 proximal promoter were hypermethylated in the liver, while hypomethylated in the kidney. On the other hand, the promoter region of OCT1 was hypermethylated in both the kidney and liver. The level of methylation of the OCT2 promoter was especially low at the CpG site in the E-box, the binding site of the basal transcription factor upstream stimulating factor (USF) 1. In vitro methylation of the OCT2 proximal promoter dramatically reduced the transcriptional activity, and an electrophoretic mobility shift assay showed that methylation at the E-box inhibited the binding of USF1. These results indicate that kidney-specific expression of human OCT2 is regulated by methylation of the proximal promoter region, interfering with the transactivation by USF1.

scholarly journals Interaction of a lens cell transcription factor with the proximal domain of the mouse gamma F-crystallin promoter.

1991 ◽  
Vol 11 (3) ◽  
pp. 1531-1537 ◽  
Author(s):  
Q R Liu ◽  
M Tini ◽  
L C Tsui ◽  
M L Breitman
Keyword(s):  
Transcription Factor ◽  
Promoter Activity ◽  
Transcriptional Activator ◽  
Tata Box ◽  
Specific Expression ◽  
Nuclear Factors ◽  
Gamma Crystallin ◽  
Lens Cells ◽  
Lens Cell

The elements regulating lens-specific expression of the mouse gamma F-crystallin gene were examined. Here we show that mouse gamma F-crystallin sequences -67 to +45 contain a low basal level of lens-specific promoter activity and that sequences -67 to -25, which are highly conserved among different gamma-crystallin genes, are able to function as a strong transcriptional activator when duplicated and placed upstream of the TATA box. We also show that nuclear factors from lens and nonlens cells are able to form different complexes with sequences centered at -46 to -36 and demonstrate that binding of the factor from lens cells correlates with lens-specific promoter activity of the mouse gamma F-crystallin gene.

Proximal promoter region is sufficient to regulate tissue-specific expression of UDP-galactose: Ceramide galactosyltransferase gene

1998 ◽  
Vol 52 (6) ◽  
pp. 757-765 ◽  
Author(s):  
Tomoko Yonemasu ◽  
Kensuke Nakahira ◽  
Syunichiro Okumura ◽  
Tetsushi Kagawa ◽  
Araceli Espinosa de los Monteros ◽  
...  
Keyword(s):  
Promoter Region ◽  
Proximal Promoter ◽  
Specific Expression ◽  
Tissue Specific ◽  
Proximal Promoter Region ◽  
Tissue Specific Expression

Interaction of a lens cell transcription factor with the proximal domain of the mouse gamma F-crystallin promoter

1991 ◽  
Vol 11 (3) ◽  
pp. 1531-1537
Author(s):  
Q R Liu ◽  
M Tini ◽  
L C Tsui ◽  
M L Breitman
Keyword(s):  
Transcription Factor ◽  
Promoter Activity ◽  
Transcriptional Activator ◽  
Tata Box ◽  
Specific Expression ◽  
Nuclear Factors ◽  
Gamma Crystallin ◽  
Lens Cells ◽  
Lens Cell

The elements regulating lens-specific expression of the mouse gamma F-crystallin gene were examined. Here we show that mouse gamma F-crystallin sequences -67 to +45 contain a low basal level of lens-specific promoter activity and that sequences -67 to -25, which are highly conserved among different gamma-crystallin genes, are able to function as a strong transcriptional activator when duplicated and placed upstream of the TATA box. We also show that nuclear factors from lens and nonlens cells are able to form different complexes with sequences centered at -46 to -36 and demonstrate that binding of the factor from lens cells correlates with lens-specific promoter activity of the mouse gamma F-crystallin gene.

scholarly journals Induced JunD in intestinal epithelial cells represses CDK4 transcription through its proximal promoter region following polyamine depletion

2007 ◽  
Vol 403 (3) ◽  
pp. 573-581 ◽  
Author(s):  
Lan Xiao ◽  
Jaladanki N. Rao ◽  
Tongtong Zou ◽  
Lan Liu ◽  
Bernard S. Marasa ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Epithelial Cells ◽  
Promoter Region ◽  
Promoter Activity ◽  
Intestinal Epithelial Cells ◽  
Ectopic Expression ◽  
Proximal Promoter ◽  
Transcriptional Level ◽  
Intestinal Epithelial ◽  
Proximal Promoter Region

Maintenance of intestinal epithelial integrity requires cellular polyamines that regulate expression of various genes involved in cell proliferation, growth arrest and apoptosis. In prior studies, depletion of cellular polyamines has been shown to stabilize JunD, a member of the AP-1 (activator protein-1) family of transcription factors, leading to inhibition of intestinal epithelial cell proliferation, but the exact downstream targets of induced JunD remain elusive. CDK4 (cyclin-dependent kinase 4) is essential for the G1- to S-phase transition during the cell cycle and its expression is primarily controlled at the transcriptional level. In the present study, we show that induced JunD in IECs (intestinal epithelial cells) is a transcriptional repressor of the CDK4 gene following polyamine depletion. Increased JunD in polyamine-deficient cells was associated with a significant inhibition of CDK4 transcription, as indicated by repression of CDK4-promoter activity and decreased levels of CDK4 mRNA and protein, all of which were prevented by using specific antisense JunD oligomers. Ectopic expression of the wild-type junD also repressed CDK4-promoter activity and decreased levels of CDK4 mRNA and protein without any effect on CDK2 expression. Gel shift and chromatin immunoprecipitation assays revealed that JunD bound to the proximal region of the CDK4-promoter in vitro as well as in vivo, while experiments using different CDK4-promoter mutants showed that transcriptional repression of CDK4 by JunD was mediated through an AP-1 binding site within this proximal sequence of the CDK4-promoter. These results indicate that induced JunD in IECs represses CDK4 transcription through its proximal promoter region following polyamine depletion.

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