Nucleosome Positioning in the Human c-FOS Promoter Analyzed by in Vivo Footprinting with Psoralen and Ionizing Radiation†

Biochemistry ◽  
2003 ◽  
Vol 42 (51) ◽  
pp. 15084-15091 ◽  
Author(s):  
Jun-ichiro Komura ◽  
Tetsuya Ono
Keyword(s):  
Ionizing Radiation ◽  
Nucleosome Positioning ◽  
In Vivo Footprinting

scholarly journals Offset of apparent hyperpolarized 13 C lactate flux by the use of adjuvant metformin in ionizing radiation therapy in vivo

2021 ◽  
Author(s):  
Young‐Suk Choi ◽  
Joonsung Lee ◽  
Han‐Sol Lee ◽  
Jae Eun Song ◽  
Dong‐Hyun Kim ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Ionizing Radiation

scholarly journals A nucleosome-positioning sequence is required for GCN4 to activate transcription in the absence of a TATA element.

1990 ◽  
Vol 10 (8) ◽  
pp. 4256-4265 ◽  
Author(s):  
C J Brandl ◽  
K Struhl
Keyword(s):  
Binding Site ◽  
Transcriptional Activation ◽  
Nucleosome Positioning ◽  
Alternative Mechanism ◽  
Tata Element ◽  
Binding Factor ◽  
Positioning Analysis ◽  
Binding Sequence

In the gal-his3 hybrid promoter his3-GG1, the yeast upstream activator protein GCN4 stimulates transcription when bound at the position normally occupied by the TATA element. This TATA-independent activation by GCN4 requires two additional elements in the gal enhancer region that are distinct from those involved in normal galactose induction. Both additional elements appear to be functionally distinct from a classical TATA element because they cannot be replaced by the TFIID-binding sequence TATAAA. One of these elements, termed Q, is essential for GCN4-activated transcription and contains the sequence GTCAC CCG, which overlaps (but is distinct from) a GAL4 binding site. Surprisingly, relatively small increases in the distance between Q and the GCN4 binding site significantly reduce the level of transcription. The Q element specifically interacts with a yeast protein (Q-binding protein [QBP]) that may be equivalent to Y, a protein that binds at a sequence that forms a constraint to nucleosome positioning. Analysis of various deletion mutants indicates that the sequence requirements for binding by QBP in vitro are indistinguishable from those necessary for Q activity in vivo, strongly suggesting that QBP is required for the function of this TATA-independent promoter. These results support the view that transcriptional activation can occur by an alternative mechanism in which the TATA-binding factor TFIID either is not required or is not directly bound to DNA. In addition, they suggest a potential role of nucleosome positioning for the activity of a promoter.

scholarly journals In Vivo Study of the Efficacy and Safety of 5-Aminolevulinic Radiodynamic Therapy for Glioblastoma Fractionated Radiotherapy

2021 ◽  
Vol 22 (18) ◽  
pp. 9762
Author(s):  
Junko Takahashi ◽  
Shinsuke Nagasawa ◽  
Motomichi Doi ◽  
Masamichi Takahashi ◽  
Yoshitaka Narita ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Aminolevulinic Acid ◽  
Combined Treatment ◽  
Reactive Oxygen Species Generation ◽  
Photodynamic Diagnosis ◽  
High Dose ◽  
Severe Toxicity ◽  
Fractionated Radiotherapy ◽  
Post Surgery

To treat malignant glioma, standard fractionated radiotherapy (RT; 60 Gy/30 fractions over 6 weeks) was performed post-surgery in combination with temozolomide to improve overall survival. Malignant glioblastoma recurrence rate is extremely high, and most recurrent tumors originate from the excision cavity in the high-dose irradiation region. In our previous study, protoporphyrin IX physicochemically enhanced reactive oxygen species generation by ionizing radiation and combined treatment with 5-aminolevulinic acid (5-ALA) and ionizing radiation, while radiodynamic therapy (RDT) improved tumor growth suppression in vivo in a melanoma mouse model. We examined the effect of 5-ALA RDT on the standard fractionated RT protocol using U251MG- or U87MG-bearing mice. 5-ALA was orally administered at 60 or 120 mg/kg, 4 h prior to irradiation. In both models, combined treatment with 5-ALA slowed tumor progression and promoted regression compared to treatment with ionizing radiation alone. The standard fractionated RT protocol of 60 Gy in 30 fractions with oral administration of 120 and 240 mg/kg 5-ALA, the human equivalent dose of photodynamic diagnosis, revealed no significant increase in toxicity to normal skin or brain tissue compared to ionizing radiation alone. Thus, RDT is expected to enhance RT treatment of glioblastoma without severe toxicity under clinically feasible conditions.

scholarly journals Impact of Ionizing Radiation on the Expression of CDC25A Phosphatase (in vivo)

2016 ◽  
Vol 10 (5) ◽  
pp. 22-26 ◽  
Author(s):  
Seyed Mostafa Mir ◽  
Esmaeil Samadian ◽  
Sahar Alijanpour ◽  
Alireza Khoshbin Khoshnazar ◽  
Hamid Haghighatfard ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Cdc25a Phosphatase

Reduced Apoptosis and Increased Deletion Mutations at Aprt Locus In vivo in Mice Exposed to Repeated Ionizing Radiation

2007 ◽  
Vol 67 (5) ◽  
pp. 1910-1917 ◽  
Author(s):  
Li Liang ◽  
Marc S. Mendonca ◽  
Li Deng ◽  
Son C. Nguyen ◽  
Changshun Shao ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Deletion Mutations

In Vivo Footprinting of the Interaction of Proteins with DNA and RNA

1997 ◽  
pp. 73-109 ◽  
Author(s):  
Thierry Grange ◽  
Gildas Rigaud ◽  
Edouard Bertrand ◽  
Micheline Fromont-Racine ◽  
Maria Lluisa Espinás ◽  
...  
Keyword(s):  
Dna And Rna ◽  
In Vivo Footprinting

A transcriptionally active tRNA gene interferes with nucleosome positioning in vivo

1992 ◽  
Vol 12 (9) ◽  
pp. 4015-4025
Author(s):  
R H Morse ◽  
S Y Roth ◽  
R T Simpson
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Trna Gene ◽  
Rna Polymerase Iii ◽  
Nucleosome Positioning ◽  
Yeast Cells ◽  
Trna Genes ◽  
Start Site ◽  
Cis Acting

Incorporation into a positioned nucleosome of a cis-acting element essential for replication in Saccharomyces cerevisiae disrupts the function of the element in vivo [R. T. Simpson, Nature (London) 343:387-389, 1990]. Furthermore, nucleosome positioning has been implicated in repression of transcription by RNA polymerase II in yeast cells. We have now asked whether the function of cis-acting elements essential for transcription of a gene transcribed by RNA polymerase III can be similarly affected. A tRNA gene was fused to either of two nucleosome positioning signals such that the predicted nucleosome would incorporate near its center the tRNA start site and essential A-box element. These constructs were then introduced into yeast cells on stably maintained, multicopy plasmids. Competent tRNA genes were transcribed in vivo and were not incorporated into positioned nucleosomes. Mutated, inactive tRNA genes were incorporated into nucleosomes whose positions were as predicted. This finding demonstrates that the transcriptional competence of the tRNA gene determined its ability to override a nucleosome positioning signal in vivo and establishes that a hierarchy exists between cis-acting elements and nucleosome positioning signals.

Sign in / Sign up

Export Citation Format

Share Document