scholarly journals Transcription factor abundance controlled by an auto-regulatory mechanism involving a transcription start site switch

2013 ◽  
Vol 42 (4) ◽  
pp. 2171-2184 ◽  
Author(s):  
Richard Patryk Ngondo ◽  
Philippe Carbon
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Transcription Start Site ◽  
Regulatory Mechanism ◽  
Start Site ◽  
Transcription Start ◽  
Aberrant Expression ◽  
Alternative Transcription ◽  
Activating Transcription Factor

Abstract A transcriptional feedback loop is the simplest and most direct means for a transcription factor to provide an increased stability of gene expression. In this work performed in human cells, we reveal a new negative auto-regulatory mechanism involving an alternative transcription start site (TSS) usage. Using the activating transcription factor ZNF143 as a model, we show that the ZNF143 low-affinity binding sites, located downstream of its canonical TSS, play the role of protein sensors to induce the up- or down-regulation of ZNF143 gene expression. We uncovered that the TSS switch that mediates this regulation implies the differential expression of two transcripts with an opposite protein production ability due to their different 5′ untranslated regions. Moreover, our analysis of the ENCODE data suggests that this mechanism could be used by other transcription factors to rapidly respond to their own aberrant expression level.

scholarly journals Control of human testis-specific gene expression

2019 ◽  
Author(s):  
Jay C. Brown
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Transcription Start Site ◽  
Binding Sites ◽  
Human Testis ◽  
Specific Gene ◽  
Start Site ◽  
Transcription Start ◽  
Control Of Gene Expression ◽  
Differentiated Cells

AbstractBackgroundAs a result of decades of effort by many investigators we now have an advanced level of understanding about several molecular systems involved in the control of gene expression. Examples include CpG islands, promoters, mRNA splicing and epigenetic signals. It is less clear, however, how such systems work together to integrate the functions of a living organism. Here I describe the results of a study to test the idea that a contribution might be made by focusing on genes specifically expressed in a particular tissue, the human testis.Experimental DesignA database of 239 testis-specific genes was accumulated and each was examined for the presence of features relevant to control of gene expression. These include: (1) the presence of a promoter, (2) the presence of a CpG island (CGI) within the promoter, (3) the presence in the promoter of a transcription factor binding site near the transcription start site, (4) the level of gene expression, and (5) the above features in genes of cell types such as spermatocyte and spermatid that differ in their extent of differentiation.ResultsOf the 107 database genes with an annotated promoter, 56 were found to have one or more transcription factor binding sites near the transcription start site. Three of the binding sites observed, Pax-5, AP-2αA and GRα, stand out in abundance suggesting they may be involved in testis-specific gene expression. Compared to less differentiated testis-specific cells, genes of more differentiated cells were found to be (1) more likely to lack a CGI, (2) more likely to lack introns and (3) higher in expression level. The results suggest genes of more differentiated cells have a reduced need for CGI-based regulatory repression, reduced usage of gene splicing and a smaller set of expressed proteins

scholarly journals A cis Repression Sequence Adjacent to the Transcription Start Site of the Human Cytomegalovirus US3 Gene Is Required To Down Regulate Gene Expression at Early and Late Times after Infection

1998 ◽  
Vol 72 (12) ◽  
pp. 9575-9584 ◽  
Author(s):  
Philip E. Lashmit ◽  
Mark F. Stinski ◽  
Eain A. Murphy ◽  
Grant C. Bullock
Keyword(s):  
Gene Expression ◽  
Viral Replication ◽  
Transcription Start Site ◽  
Human Cytomegalovirus ◽  
Maximum Level ◽  
Start Site ◽  
Wild Type ◽  
Transcription Start ◽  
Recombinant Viruses

ABSTRACT Human cytomegalovirus has two enhancer-containing immediate-early (IE) promoters with a cis repression sequence (CRS) positioned immediately upstream of the transcription start site, designated the major IE (MIE) promoter and the US3 promoter. The role of the CRS upstream of the US3 transcription start site in the context of the viral genome was determined by comparing the levels of transcription from these two enhancer-containing promoters in recombinant viruses with a wild-type or mutant CRS. Upstream of the CRS of the US3 promoter was either the endogenous enhancer (R2) or silencer (R1). The downstream US3 gene was replaced with the indicator gene chloramphenicol acetyltransferase (CAT). Infected permissive human fibroblast cells or nonpermissive, undifferentiated monocytic THP-1 cells were analyzed for expression from the US3 promoter containing either the wild-type or mutant CRS. With the wild-type CRS, the maximum level of transcription in permissive cells was detected within 4 to 6 h after infection and then declined. With the mutant CRS and the R2 enhancer upstream, expression from the US3 promoter continued to increase throughout the viral replication cycle to levels 20- to 40-fold higher than for the wild type. In nonpermissive or permissive monocytic THP-1 cells, expression from the US3 promoter was also significantly higher when the CRS was mutated. Less expression was obtained when only the R1 element was present, but expression was higher when the CRS was mutated. Thus, the CRS in the enhancer-containing US3 promoter appears to allow for a short burst of US3 gene expression followed by repression at early and late times after infection. Overexpression of US3 may be detrimental to viral replication, and its level of expression must be stringently controlled. The role of the CRS and the viral IE86 protein in controlling enhancer-containing promoters is discussed.

The Role of XPB/Ssl2 dsDNA Translocase Processivity in Transcription Start-site Scanning

2021 ◽  
pp. 166813
Author(s):  
Eric J. Tomko ◽  
Olivia Luyties ◽  
Jenna K. Rimel ◽  
Chi-Lin Tsai ◽  
Jill O. Fuss ◽  
...  
Keyword(s):  
Transcription Start Site ◽  
Start Site ◽  
Transcription Start

scholarly journals Sequence of the 5′-flanking region and promoter activity of the human mucin gene MUC5B in different phenotypes of colon cancer cells

2000 ◽  
Vol 348 (3) ◽  
pp. 675-686 ◽  
Author(s):  
Isabelle VAN SEUNINGEN ◽  
Michaël PERRAIS ◽  
Pascal PIGNY ◽  
Nicole PORCHET ◽  
Jean-Pierre AUBERT
Keyword(s):  
Gene Expression ◽  
Transcription Start Site ◽  
Promoter Activity ◽  
Luciferase Reporter ◽  
Nuclear Factor ◽  
Start Site ◽  
Transcription Start ◽  
Mucin Gene ◽  
Intron 1 ◽  
Flanking Region

Control of gene expression in intestinal cells is poorly understood. Molecular mechanisms that regulate transcription of cellular genes are the foundation for understanding developmental and differentiation events. Mucin gene expression has been shown to be altered in many intestinal diseases and especially cancers of the gastrointestinal tract. Towards understanding the transcriptional regulation of a member of the 11p15.5 human mucin gene cluster, we have characterized 3.55 kb of the 5ʹ-flanking region of the human mucin gene MUC5B, including the promoter, the first two exons and the first intron. We report here the promoter activity of successively 5ʹ-truncated sections of 956 bases of this region by fusing it to the coding region of a luciferase reporter gene. The transcription start site was determined by primer-extension analysis. The region upstream of the transcription start site is characterized by the presence of a TATA box at bases -32/-26, DNA-binding elements for transcription factors c-Myc, N-Myc, Sp1 and nuclear factor ĸB as well as putative activator protein (AP)-1-, cAMP-response-element-binding protein (CREB)-, hepatocyte nuclear factor (HNF)-1-, HNF-3-, TGT3-, gut-enriched Krüppel factor (GKLF)-, thyroid transcription factor (TTF)-1- and glucocorticoid receptor element (GRE)-binding sites. Intron 1 of MUC5B was also characterized, it is 2511 nucleotides long and contains a DNA segment of 259 bp in which are clustered eight tandemly repeated GA boxes and a CACCC box that bind Sp1. AP-2α and GATA-1 nuclear factors were also shown to bind to their respective cognate elements in intron 1. In transfection studies the MUC5B promoter showed a cell-specific activity as it is very active in mucus-secreting LS174T cells, whereas it is inactive in Caco-2 enterocytes and HT-29 STD (standard) undifferentiated cells. Within the promoter, maximal transcription activity was found in a segment covering the first 223 bp upstream of the transcription start site. Finally, in co-transfection experiments a transactivating effect of Sp1 on to MUC5B promoter was seen in LS174T and Caco-2 cells.

scholarly journals Transcription Regulation by Tandem-Bound FNR at Escherichia coli Promoters

2003 ◽  
Vol 185 (20) ◽  
pp. 5993-6004 ◽  
Author(s):  
Anne M. L. Barnard ◽  
Jeffrey Green ◽  
Stephen J. W. Busby
Keyword(s):  
Escherichia Coli ◽  
Transcription Factor ◽  
Binding Site ◽  
Transcription Regulation ◽  
Transcription Start Site ◽  
Promoter Activity ◽  
Start Site ◽  
Transcription Start ◽  
Substitution Mutant

ABSTRACT FNR is an Escherichia coli transcription factor that regulates the transcription of many genes in response to anaerobiosis. We have constructed a series of artificial FNR-dependent promoters, based on the melR promoter, in which a consensus FNR binding site was centered at position −41.5 relative to the transcription start site. A second consensus FNR binding site was introduced at different upstream locations, and promoter activity was assayed in vivo. FNR can activate transcription from these promoters when the upstream FNR binding site is located at many different positions. However, sharp repression is observed when the upstream-bound FNR is located near positions −85 or −95. This repression is relieved by the FNR G74C substitution mutant, previously identified as being defective in transcription repression at the yfiD promoter. A parallel series of artificial FNR-dependent promoters, carrying a consensus FNR binding site at position −61.5 and a second upstream DNA site for FNR, was also constructed. Again, promoter activity was repressed by FNR when the upstream-bound FNR was located at particular positions.

scholarly journals FIS activatesglnAp2 inEscherichia coli: role of a DNA bend centered at −55, upstream of the transcription start site

2006 ◽  
Vol 257 (1) ◽  
pp. 99-105 ◽  
Author(s):  
Yi-Xin Huo ◽  
Bei-Yan Nan ◽  
Cong-Hui You ◽  
Zhe-Xian Tian ◽  
Annie Kolb ◽  
...  
Keyword(s):  
Transcription Start Site ◽  
Inescherichia Coli ◽  
Start Site ◽  
Transcription Start
Sign in / Sign up

Export Citation Format

Share Document