scholarly journals Radiation Desiccation Response Motif-Like Sequences Are Involved in Transcriptional Activation of the Deinococcal ssb Gene by Ionizing Radiation but Not by Desiccation

2010 ◽  
Vol 192 (21) ◽  
pp. 5637-5644 ◽  
Author(s):  
Aman Kumar Ujaoney ◽  
Akhilesh A. Potnis ◽  
Pratiksha Kane ◽  
Rita Mukhopadhyaya ◽  
Shree Kumar Apte
Keyword(s):  
Mitomycin C ◽  
Gamma Rays ◽  
Transcriptional Activation ◽  
Promoter Region ◽  
Deinococcus Radiodurans ◽  
Dna Binding Protein ◽  
Similar Sequence ◽  
Reading Frame ◽  
Transcriptional Induction ◽  
Transcriptional Fusions

ABSTRACT Single-stranded-DNA binding protein (SSB) levels during poststress recovery of Deinococcus radiodurans were significantly enhanced by 60Co gamma rays or mitomycin C treatment but not by exposure to UV rays, hydrogen peroxide (H2O2), or desiccation. Addition of rifampin prior to postirradiation recovery blocked such induction. In silico analysis of the ssb promoter region revealed a 17-bp palindromic radiation/desiccation response motif (RDRM1) at bp −114 to −98 and a somewhat similar sequence (RDRM2) at bp −213 to −197, upstream of the ssb open reading frame. Involvement of these cis elements in radiation-responsive ssb gene expression was assessed by constructing transcriptional fusions of edited versions of the ssb promoter region with a nonspecific acid phosphatase encoding reporter gene, phoN. Recombinant D. radiodurans strains carrying such constructs clearly revealed (i) transcriptional induction of the ssb promoter upon irradiation and mitomycin C treatment but not upon UV or H2O2 treatment and (ii) involvement of both RDRM-like sequences in such activation of SSB expression, in an additive manner.

scholarly journals Elevated Expression of Toxin TisB Protects Persister Cells against Ciprofloxacin but Enhances Susceptibility to Mitomycin C

2021 ◽  
Vol 9 (5) ◽  
pp. 943
Author(s):  
Daniel Edelmann ◽  
Florian H. Leinberger ◽  
Nicole E. Schmid ◽  
Markus Oberpaul ◽  
Till F. Schäberle ◽  
...  
Keyword(s):  
Dna Damage ◽  
Mitomycin C ◽  
Transcriptional Activation ◽  
Structural Features ◽  
Atp Depletion ◽  
Transcriptional Level ◽  
Persister Cells ◽  
Sos Induction ◽  
Bacterial Chromosomes ◽  
Elevated Expression

Bacterial chromosomes harbor toxin-antitoxin (TA) systems, some of which are implicated in the formation of multidrug-tolerant persister cells. In Escherichia coli, toxin TisB from the tisB/istR-1 TA system depolarizes the inner membrane and causes ATP depletion, which presumably favors persister formation. Transcription of tisB is induced upon DNA damage due to activation of the SOS response by LexA degradation. Transcriptional activation of tisB is counteracted on the post-transcriptional level by structural features of tisB mRNA and RNA antitoxin IstR-1. Deletion of the regulatory RNA elements (mutant Δ1-41 ΔistR) uncouples TisB expression from LexA-dependent SOS induction and causes a ‘high persistence’ (hip) phenotype upon treatment with different antibiotics. Here, we demonstrate by the use of fluorescent reporters that TisB overexpression in mutant Δ1-41 ΔistR inhibits cellular processes, including the expression of SOS genes. The failure in SOS gene expression does not affect the hip phenotype upon treatment with the fluoroquinolone ciprofloxacin, likely because ATP depletion avoids strong DNA damage. By contrast, Δ1-41 ΔistR cells are highly susceptible to the DNA cross-linker mitomycin C, likely because the expression of SOS-dependent repair systems is impeded. Hence, the hip phenotype of the mutant is conditional and strongly depends on the DNA-damaging agent.

scholarly journals The E-box DNA binding protein Sgc1p suppresses thegcr2mutation, which is involved in transcriptional activation of glycolytic genes inSaccharomyces cerevisiae

FEBS Letters ◽  
1999 ◽  
Vol 463 (3) ◽  
pp. 307-311 ◽  
Author(s):  
Takashi Sato ◽  
M.Cecilia Lopez ◽  
Shigemi Sugioka ◽  
Yoshifumi Jigami ◽  
Henry V. Baker ◽  
...  
Keyword(s):  
Dna Binding ◽  
Transcriptional Activation ◽  
Binding Protein ◽  
Dna Binding Protein ◽  
E Box

Identical genomic footprints of the adenovirus EIIa promoter are detected before and after EIa induction

1987 ◽  
Vol 7 (12) ◽  
pp. 4560-4563
Author(s):  
B Devaux ◽  
G Albrecht ◽  
C Kedinger
Keyword(s):  
Transcription Factors ◽  
Protein Binding ◽  
Promoter Region ◽  
Adenovirus Type ◽  
Specific Protein ◽  
Dnase I ◽  
Dnase I Footprinting ◽  
Before And After ◽  
Adenovirus Type 5 ◽  
Transcriptional Induction

Genomic DNase I footprinting was used to compare specific protein binding to the adenovirus type 5 early, EIa-inducible, EIIa promoter. Identical protection patterns of the promoter region were observed whether EIIa transcription was undetectable or fully induced. These results suggest that EIa-mediated transcriptional induction does not increase binding of limiting transcription factors to the promoter but rather that transactivation results from the proper interactions between factors already bound to their cognate sequences.

Interspersion of an unusual GCN4 activation site with a complex transcriptional repression site in Ty2 elements of Saccharomyces cerevisiae

1993 ◽  
Vol 13 (4) ◽  
pp. 2091-2103
Author(s):  
S Türkel ◽  
P J Farabaugh
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Transcriptional Activation ◽  
Binding Sites ◽  
Transcriptional Repression ◽  
Physiological Control ◽  
Reading Frame ◽  
Negative Region ◽  
Activation Site

Transcription of the Ty2-917 retrotransposon of Saccharomyces cerevisiae is modulated by a complex set of positive and negative elements, including a negative region located within the first open reading frame, TYA2. The negative region includes three downstream repression sites (DRSI, DRSII, and DRSIII). In addition, the negative region includes at least two downstream activation sites (DASs). This paper concerns the characterization of DASI. A 36-bp DASI oligonucleotide acts as an autonomous transcriptional activation site and includes two sequence elements which are both required for activation. We show that these sites bind in vitro the transcriptional activation protein GCN4 and that their activity in vivo responds to the level of GCN4 in the cell. We have termed the two sites GCN4 binding sites (GBS1 and GBS2). GBS1 is a high-affinity GCN4 binding site (dissociation constant, approximately 25 nM at 30 degrees C), binding GCN4 with about the affinity of a consensus UASGCN4, this though GBS1 includes two differences from the right half of the palindromic consensus site. GBS2 is more diverged from the consensus and binds GCN4 with about 20-fold-lower affinity. Nucleotides 13 to 36 of DASI overlap DRSII. Since DRSII is a transcriptional repression site, we tested whether DASI includes repression elements. We identify two sites flanking GBS2, both of which repress transcription activated by the consensus GCN4-specific upstream activation site (UASGCN4). One of these is repeated in the 12 bp immediately adjacent to DASI. Thus, in a 48-bp region of Ty2-917 are interspersed two positive and three negative transcriptional regulators. The net effect of the region must depend on the interaction of the proteins bound at these sites, which may include their competing for binding sites, and on the physiological control of the activity of these proteins.

scholarly journals Characterization of a Chlamydia psittaciDNA Binding Protein (EUO) Synthesized during the Early and Middle Phases of the Developmental Cycle

1998 ◽  
Vol 66 (3) ◽  
pp. 1167-1173 ◽  
Author(s):  
Li Zhang ◽  
Annemarie L. Douglas ◽  
Thomas P. Hatch
Keyword(s):  
Promoter Region ◽  
Chlamydia Psittaci ◽  
Host Cells ◽  
Upstream Open Reading Frame ◽  
Developmental Cycle ◽  
Binding Property ◽  
Logarithmic Growth Phase ◽  
Reading Frame

ABSTRACT The EUO gene (for early upstream open reading frame) ofChlamydia psittaci was previously found to be transcribed better at 1 than at 24 h postinfection. We found that the EUO gene encodes a minor protein that is expressed within 1 h of infection of host cells with C. psittaci 6BC but that protein quantity peaks during the logarithmic growth phase of reticulate bodies (RBs), declines late in the infection (after 20 h) when RBs reorganize into elementary bodies (EBs), and is absent in infectious EBs. EUO protein lacks homology to known proteins but does contain a putative helix-turn-helix motif. We found that recombinant EUO binds to DNA in vitro with a relatively broad specificity. Using the bp −200 to +67 promoter region of the cysteine-rich envelope protein (crp) operon as a model, we show that EUO protein preferentially binds to AT-rich sequences and protects crpDNA from DNase I from approximately bp −60 to −9. We also found that native EUO protein in extracts of RBs binds to the promoter region of the crp operon, demonstrating that the DNA binding property of EUO protein is not an artifact of recombinant methods. Although EUO protein appears to bind to the crp operon with high affinity in vitro (Kd of about 15 nM), it is not known whether the protein binds the crp DNA in vivo.

scholarly journals Epithelial-Mesenchymal Transition Induces GSDME Transcriptional Activation for Inflammatory Pyroptosis

2021 ◽  
Vol 9 ◽  
Author(s):  
Chenqiang Jia ◽  
Zhuqing Zhang ◽  
Jun Tang ◽  
Mei-Chun Cai ◽  
Jingyu Zang ◽  
...  
Keyword(s):  
Cell Death ◽  
Transcriptional Activation ◽  
Promoter Region ◽  
Drug Exposure ◽  
Epithelial Mesenchymal Transition ◽  
Experimental Models ◽  
Cytokine Release ◽  
Functional Importance ◽  
Bioinformatics Analyses ◽  
Mesenchymal Transition

GSDME is a newly recognized executor of cellular pyroptosis, and has been recently implicated in tumor growth and immunity. However, knowledge about the molecular regulators underlying GSDME abundance remains limited. Here, we performed integrative bioinformatics analyses and identified that epithelial-mesenchymal transition (EMT) gene signatures exhibited positive correlation with GSDME levels across human cancers. A causal role was supported by the observation that EMT dictated GSDME reversible upregulation in multiple experimental models. Mechanistically, transcriptional activation of GSDME was directly driven by core EMT-activating transcription factors ZEB1/2, which bound to the GSDME promoter region. Of functional importance, elevated GSDME in mesenchymally transdifferentiated derivatives underwent proteolytic cleavage upon antineoplastic drug exposure, leading to pyroptotic cell death and consequent cytokine release. Taken together, our findings pinpointed a key transcriptional machinery controlling GSDME expression and indicated potential therapeutic avenues to exploit GSDME-mediated inflammatory pyroptosis for the treatment of mesenchymal malignancies.

scholarly journals Transcriptional activation upon pheromone stimulation mediated by a small domain of Saccharomyces cerevisiae Ste12p.

1997 ◽  
Vol 17 (11) ◽  
pp. 6410-6418 ◽  
Author(s):  
H Pi ◽  
C T Chien ◽  
S Fields
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Map Kinase ◽  
Transcriptional Activation ◽  
Transcriptional Activity ◽  
Activation Domain ◽  
Yeast Saccharomyces Cerevisiae ◽  
Activation Domains ◽  
Hybrid Proteins ◽  
High Level ◽  
Transcriptional Induction

In the yeast Saccharomyces cerevisiae, Ste12p induces transcription of pheromone-responsive genes by binding to a DNA sequence designated the pheromone response element. We generated a series of hybrid proteins of Ste12p with the DNA-binding and activation domains of the transcriptional activator Gal4p to define a pheromone induction domain of Ste12p sufficient to mediate pheromone-induced transcription by these hybrid proteins. A minimal pheromone induction domain, delineated as residues 301 to 335 of Ste12p, is dependent on the pheromone mitogen-activated protein (MAP) kinase pathway for induction activity. Mutation of the three serine and threonine residues within the minimal pheromone induction domain did not affect transcriptional induction, indicating that the activity of this domain is not directly regulated by MAP kinase phosphorylation. By contrast, mutation of the two tyrosines or their preceding acidic residues led to a high level of transcriptional activity in the absence of pheromone and consequently to the loss of pheromone induction. This constitutively high activity was not affected by mutations in the MAP kinase cascade, suggesting that the function of the pheromone induction domain is normally repressed in the absence of pheromone. By two-hybrid analysis, this minimal domain interacts with two negative regulators, Dig1p and Dig2p (also designated Rst1p and Rst2p), and the interaction is abolished by mutation of the tyrosines. The pheromone induction domain itself has weak and inducible transcriptional activity, and its ability to potentiate transcription depends on the activity of an adjacent activation domain. These results suggest that the pheromone induction domain of Ste12p mediates transcriptional induction via a two-step process: the relief of repression and synergistic transcriptional activation with another activation domain.

scholarly journals RbsR Activates Capsule but Represses therbsUDKOperon in Staphylococcus aureus

2015 ◽  
Vol 197 (23) ◽  
pp. 3666-3675 ◽  
Author(s):  
Mei G. Lei ◽  
Chia Y. Lee
Keyword(s):  
Staphylococcus Aureus ◽  
Virulence Factor ◽  
Transcriptional Activation ◽  
Promoter Region ◽  
Mobility Shift ◽  
Content Type ◽  
Virulence Regulation ◽  
Important Virulence Factor ◽  
Dna Fragment ◽  
Mobility Shift Assay

ABSTRACTStaphylococcus aureuscapsule is an important virulence factor that is regulated by a large number of regulators. Capsule genes are expressed from a major promoter upstream of thecapoperon. A 10-bp inverted repeat (IR) located 13 bp upstream of the −35 region of the promoter was previously shown to affect capsule gene transcription. However, little is known about transcriptional activation of thecappromoter. To search for potential proteins which directly interact with thecappromoter region (Pcap), we directly analyzed the proteins interacting with the PcapDNA fragment from shifted gel bands identified by electrophoretic mobility shift assay. One of these regulators, RbsR, was further characterized and found to positively regulatecapgene expression by specifically binding to thecappromoter region. Footprinting analyses showed that RbsR protected a DNA region encompassing the 10-bp IR. Our results further showed thatrbsRwas directly controlled by SigB and that RbsR was a repressor of therbsUDKoperon, involved in ribose uptake and phosphorylation. The repression ofrbsUDKby RbsR could be derepressed byd-ribose. However,d-ribose did not affect RbsR activation of capsule.IMPORTANCEStaphylococcus aureusis an important human pathogen which produces a large number of virulence factors. We have been using capsule as a model virulence factor to study virulence regulation. Although many capsule regulators have been identified, the mechanism of regulation of most of these regulators is unknown. We show here that RbsR activates capsule by direct promoter binding and that SigB is required for the expression ofrbsR. These results define a new pathway wherein SigB activates capsule through RbsR. Our results further demonstrate that RbsR inhibits therbsoperon involved in ribose utilization, thereby providing an example of coregulation of metabolism and virulence inS. aureus. Thus, this study further advances our understanding of staphylococcal virulence regulation.

scholarly journals Peroxisome Proliferator-Activated Receptor-γ Antagonizes LOX-1-Mediated Endothelial Injury by Transcriptional Activation of miR-590-5p

PPAR Research ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Lei Xu ◽  
Gang Zhao ◽  
Hong Zhu ◽  
Shijun Wang ◽  
Aijun Sun ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Transcriptional Activation ◽  
Promoter Region ◽  
Nuclear Translocation ◽  
Therapeutic Potential ◽  
Umbilical Vein ◽  
Density Lipoprotein ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor

Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is one of the major receptors expressed on the endothelium of arterial wall with a key role in endothelial dysfunction and the development of atherosclerosis. Recent evidence suggested that LOX-1 is upregulated under the condition of insulin resistance and could be suppressed by the antidiabetic drugs. We previously also confirmed that Thiazolidinedione (TZD) has the inhibitory effect on LOX-1 in ox-LDL-induced endothelial cells. However, the underlying mechanism is unclear. Here we showed that Rosiglitazone treatment significantly attenuated the expressions of LOX-1, ICAM-1, VCAM-1, p47phox, and the atherosclerotic lesions in ApoE-/- mice with high-fat diet. In vitro, we revealed that Rosiglitazone inhibited LOX-1 by regulating miR-590-5p. Ox-LDL-mediated ICAM-1, VCAM-1, and p47phox were significantly reduced by Rosiglitazone, but all reversed after pretreating the cells with antagomiR-590-5p. Induction with Rosiglitazone activated PPAR-γ and promoted its nuclear translocation in cultured human umbilical vein endothelial cells (HUVECs). The nuclear PPAR-γ upregulated the miR-590-5p level through binding to its transcriptional promoter region. Retaining PPAR-γ in cytoplasm by transfecting with PPAR-γ⊿NLS plasmid in HUVECs failed to activate miR-590-5p. Mutation of the promoter region of PPAR-γ also reduced the miR-590-5p promoter luciferase activity. Collectively, these data indicated that PPAR-γ may have the therapeutic potential in atherosclerosis via the transcriptional regulation of miR-590-5p in endothelial cells.

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