A dual enhancer-silencer element, DES-K16, in mouse spermatocyte-derived GC-2spd(ts) cells

Vimentin, a member of the intermediate filament protein family, exhibits tissue- as well as development-specific expression. Transcription factors that are involved in expression of the chicken vimentin gene have been described and include a cis-acting silencer element (SE3) that is involved in the down-regulation of this gene (F. X. Farrell, C. M. Sax, and Z. E. Zehner, Mol. Cell. Biol. 10:2349-2358, 1990). In this study, we report the identification of two additional silencer elements (SE1 and SE2). We show by transfection analysis that all three silencer elements are functionally active and that optimal silencing occurs when multiple (at least two) silencer elements are present. In addition, the previously identified SE3 can be divided into three subregions, each of which is moderately active alone. By gel mobility shift assays, all three silencer elements plus SE3 subregions bind a protein which by Southwestern (DNA-protein) blot analysis is identical in molecular mass (approximately 95 kDa). DNase I footprinting experiments indicate that this protein binds to purine-rich sites. Therefore, multiple elements appear to be involved in the negative regulation of the chicken vimentin gene, which may be important in the regulation of other genes as well.

Download Full-text

Negative regulation of catalase gene expression in hepatoma cells

Molecular and Cellular Biology ◽

10.1128/mcb.12.6.2525-2533.1992 ◽

1992 ◽

Vol 12 (6) ◽

pp. 2525-2533

Author(s):

K Sato ◽

K Ito ◽

H Kohara ◽

Y Yamaguchi ◽

K Adachi ◽

...

Keyword(s):

Rat Liver ◽

Catalase Activity ◽

Hepatoma Cell ◽

Nuclear Extract ◽

Hepatoma Cells ◽

Negative Regulation ◽

Regulation Of Transcription ◽

Catalase Gene ◽

Core Sequence ◽

Silencer Element

For an understanding of the molecular basis of the marked decrease in catalase activity of various tumor cells, expression of the catalase gene was studied in rat and human hepatoma cell lines and in rat liver, which was used as a control with high activity. RNA blot hybridization profiles and run-on assays indicated that the decrease in catalase activity was due to depression of catalase gene transcription. Chloramphenicol acetyltransferase (CAT) assays for the fragments with various lengths of the 5'-flanking region (up to -4.5 kb from the ATG codon) of the catalase gene revealed the presence of several cis-acting elements involved in the negative regulation of transcription. The most-upstream element with the strongest activity (-3504 to -3364 bp), when linked to the catalase promoter region (-126 bp) of the CAT construct and subjected to an in vitro transcription assay, did not yield transcripts in experiments with the hepatoma nuclear extract, whereas the unlinked template did yield transcripts. A gel shift competition assay using hepatoma nuclear extract showed the core sequence of the silencer element to be 5'-TGGGGGGAG-3'. A homology search found that the same core sequence was also present in 5'-flanking regions of the albumin gene and of some other liver enzyme genes, the expression of which has been reported to be down regulated in some hepatoma cells. Southwestern (DNA-protein) analysis demonstrated that an approximately 35-kDa nuclear protein bound to the silencer element was present in hepatoma cells but not in rat liver cells.

Download Full-text

The neuron-restrictive silencer element: A dual enhancer/silencer crucial for patterned expression of a nicotinic receptor gene in the brain

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.94.11.5906 ◽

1997 ◽

Vol 94 (11) ◽

pp. 5906-5911 ◽

Cited By ~ 93

Author(s):

A. Bessis ◽

N. Champtiaux ◽

L. Chatelin ◽

J.-P. Changeux

Keyword(s):

Nicotinic Receptor ◽

Receptor Gene ◽

Silencer Element ◽

The Brain

Download Full-text

Activation of the Human Aldehyde Oxidase (hAOX1) Promoter by Tandem Cooperative Sp1/Sp3 Binding Sites: Identification of Complex Architecture in thehAOX Upstream DNA that Includes a Proximal Promoter, Distal Activation Sites, and a Silencer Element

DNA and Cell Biology ◽

10.1089/10445490050128395 ◽

2000 ◽

Vol 19 (8) ◽

pp. 459-474 ◽

Cited By ~ 9

Author(s):

Richard M. Wright ◽

Mary G. Riley ◽

Laura K. Weigel ◽

Lisa A. Ginger ◽

David A. Costantino ◽

...

Keyword(s):

Binding Sites ◽

Aldehyde Oxidase ◽

Proximal Promoter ◽

Complex Architecture ◽

Silencer Element

Download Full-text

A silencer element from the alpha-globin gene inhibits expression of beta-like genes

Molecular and Cellular Biology ◽

10.1128/mcb.8.11.5047-5051.1988 ◽

1988 ◽

Vol 8 (11) ◽

pp. 5047-5051

Author(s):

G F Atweh ◽

J M Liu ◽

H E Brickner ◽

X X Zhu

Keyword(s):

Globin Gene ◽

Expression System ◽

Globin Genes ◽

Beta Globin ◽

Base Pair Fragment ◽

Alpha Globin ◽

In Trans ◽

Cis And Trans ◽

In Cis ◽

Silencer Element

We have studied the cis and trans interactions of the alpha- and beta-globin genes in a transient expression system. We found that the alpha-globin gene inhibited beta-globin expression in cis but not in trans. The silencer element responsible for this inhibition was localized to a 259-base-pair fragment at the 5' end of the alpha-globin gene.

Download Full-text