Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:4.1.99.3 (
PRE
)
1,923
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Positive regulatory element I (PRE-I) is a strong enhancer element essential for expression of the human IL-4 gene. To identify transcription factors binding to
PRE
-I, we screened a cDNA expression library from Jurkat T cells and isolated a cDNA encoding nuclear factor (NF)-IL6 (also known as C/EBP beta). NF-IL6 mRNA was found in human Jurkat T cells and in the mouse Th2 clone
D10
, but not in Th1 clone 29. rNF-IL6 expressed in bacteria was shown to specifically bind to
PRE
-I.
PRE
-I forms multiple DNA-protein complexes with nuclear extracts from Jurkat cells. Some of these complexes were demonstrated to contain NF-IL6 by using anti-C/EBP beta Abs. Overexpression of NF-IL6 enhanced expression of the chloramphenicol acetyl transferase reporter gene linked to the
PRE
-I-thymidine kinase or the human IL-4 promoter more than 10-fold in Jurkat cells. Promoter deletion studies revealed two additional NF-IL6 binding sites located at positions -44 to -36 (C/EBP proximal) and -87 to -79 (C/EBP medial), respectively. Our results demonstrate that NF-IL6 is involved in transcriptional activation of the human IL-4 promoter in T cells.
...
PMID:Nuclear factor-IL6 activates the human IL-4 promoter in T cells. 759 40
Cis-acting regions in the 5'-flank of the mouse interleukin 5 (IL-5) gene involved in the specific and inducible regulation of IL-5 transcription in an untransformed mouse T cell clone,
D10
.G4.1, have been identified. Transient transfection assays with a series of deletion IL-5 promoter reporter constructs indicate that multiple regulatory elements in the 5'-flanking region of the IL-5 promoter play a role in regulating IL-5 transcription in Th2 cells. Negatively acting elements, NRE I and NRE II, map to the regions between positions -431 and -392 and positions -300 and -261. A positive regulatory element has been mapped to the region between positions -224 and -81. The activity of these elements is dependent on activation of the cells. A 40-bp sequence within this region, termed the IL-5
PRE
, has been shown to bind at least two specific nuclear protein complexes from unstimulated and stimulated
D10
.G4.1 cells. An additional protein complex specific for this site has been identified in nuclear fractions from cells stimulated in the presence of the protein synthesis inhibitor, cycloheximide. Proteins that bind to these elements are likely to be important inducible and specific factors essential for control of IL-5 transcription in response to T cell receptor-mediated signaling events.
...
PMID:Transcription of the murine interleukin 5 gene is regulated by multiple promoter elements. 765 35
The immunomodulatory cytokine IL-4 affects cells of most hemopoietic lineages. IL-4 is secreted by activated Th2 but not Th1 cells and plays a major role in the immune response by modulating the differentiation of naive Th cells toward the Th2 phenotype. We have previously identified an enhancer element,
PRE
-I, that is essential for the function of the human IL-4 promoter. To investigate the mechanisms responsible for tissue-specific expression of the IL-4 gene, we analyzed nuclear factors binding to the
PRE
-I site and compared the binding activities of these factors to the IL-4 promoter of Th1 and Th2 cells. We show that
PRE
-I interacts with PMA- and PMA/ionomycin-inducible, cyclosporin A-sensitive nuclear factors. Using anti-C/EBPbeta (NF-IL6), anti-C/EBPdelta (NF-IL6beta), anti-NF-ATc, anti-NF-ATp, anti-Fos, and anti-Jun Abs we demonstrate that the previously identified
PRE
-I binding factor POS-1 is composed of different transcription factors in different Th cell subsets. In the IL-4-producing Th0-like human Jurkat and mouse EL-4 cells, POS-1 (designated POS-1a) contains NF-IL6beta and Jun. In the mouse Th2
D10
cells and in the human Th2 clones, POS-1 (designated POS-1b) contains NF-IL6beta, Jun, and NF-ATc/p. In contrast, POS-1 was not found in nuclear extracts of human Th1 clones. These findings suggest that
PRE
-I may play a role in the differential regulation of IL-4 gene expression levels.
...
PMID:Differential interaction of nuclear factors with the PRE-I enhancer element of the human IL-4 promoter in different T cell subsets. 901 59