Search results for " Transcription factor"

RB1 in cancer: Different mechanisms of RB1 inactivation and alterations of pRb pathway in tumorigenesis

2013

Loss of RB1 gene is considered either a causal or an accelerating event in retinoblastoma. A variety of mechanisms inactivates RB1 gene, including intragenic mutations, loss of expression by methylation and chromosomal deletions, with effects which are species-and cell type-specific. RB1 deletion can even lead to aneuploidy thus greatly increasing cancer risk. The RB1gene is part of a larger gene family that includes RBL1 and RBL2, each of the three encoding structurally related proteins indicated as pRb, p107, and p130, respectively. The great interest in these genes and proteins springs from their ability to slow down neoplastic growth. pRb can associate with various proteins by which it …

Polymorphism and chromosomal localization of the porcine signal transducer and activator of transcription 5B gene (STAT5B).

2006

Signal transducers and activators of transcription (STATs) are a family of transcription factors. STAT5A and 5B are two highly related proteins encoded by two distinct genes. Transgenic knockout mice studies have indicated the importance of STAT5 proteins for the regulation of both lactation and growth performance. Moreover, different studies determine the role of STAT5 proteins in the modulation of adipocyte function. In this study, we sequenced one fragment of STAT5B gene from animals of six breeds (Duroc, Iberian, Landrace, Large White, Pie´train and Meishan) to identify genetic variants. A G/A single nucleotide polymorphism in intron 14 creates a polymorphic PstI restriction site and wa…

Assignment of signal transducer and activator of transcription 5A (STAT5A) to porcine chromosome 12p13→p11 by radiation hybrid panel mapping

2005

What do you mean by transcription rate?

2013

mRNA synthesis in all organisms is performed by RNA polymerases, which work as nanomachines on DNA templates. The rate at which their product is made is an important parameter in gene expression. Transcription rate encompasses two related, yet different, concepts: the nascent transcription rate, which measures the in situ mRNA production by RNA polymerase, and the rate of synthesis of mature mRNA, which measures the contribution of transcription to the mRNA concentration. Both parameters are useful for molecular biologists, but they are not interchangeable and they are expressed in different units. It is important to distinguish when and where each one should be used. We propose that for fu…

Redox regulation of genome stability by effects on gene expression, epigenetic pathways and DNA damage/repair

2015

Reactive oxygen and nitrogen species (e.g. H2O2, nitric oxide) confer redox regulation of essential cellular signaling pathways such as cell differentiation, proliferation, migration and apoptosis. In addition, classical regulation of gene expression or activity, including gene transcription to RNA followed by translation to the protein level, by transcription factors (e.g. NF-κB, HIF-1α) and mRNA binding proteins (e.g. GAPDH, HuR) is subject to redox regulation. This review will give an update of recent discoveries in this field, and specifically highlight the impact of reactive oxygen and nitrogen species on DNA repair systems that contribute to genomic stability. Emphasis will be placed …

A distinct subset of HLA-DR+-regulatory T cells is involved in the induction of preterm labor during pregnancy and in the induction of organ rejectio…

2010

Regulatory T cells (Tregs) are known to suppress alloimmune responses during pregnancy and post organ transplantation. We demonstrate that a distinct subset of FoxP3(+)DR(+)-Tregs among the total CD4(+)CD127(low+/-)CD25(+)-Treg cell pool is critically involved in preterm labor induction and kidney transplant rejection as well. Compared to healthy pregnancies and non-rejecting kidney recipients, we found that the percentage of the FoxP3(+)DR(+)-Treg subset was not reduced, but that the level of HLA-DR expression of such Tregs was strongly diminished in preterm laboring women and in patients with acute renal allograft rejection. In addition, both patient collectives showed a significantly red…

8-Oxo-7,8-dihydroguanine in DNA does not constitute a barrier to transcription, but is converted into transcription-blocking damage by OGG1.

2011

The common DNA base modification 8-oxo-7,8-dihydroguanine (8-oxo-G) affects the efficiency and fidelity of transcription. We constructed plasmid substrates carrying single 8-oxo-G residues, specifically positioned in the transcribed or the non-transcribed DNA strands, to investigate their effects on the expression of an EGFP reporter gene and to explore the role of base excision repair in the mechanism of transcription inhibition. We report that 8-oxo-G does not directly block transcription in cells, since a single 8-oxo-G in the transcribed DNA strand did not reduce the EGFP expression levels in repair-deficient (OGG1-null) mouse embryonic fibroblast cell lines. Rather, inhibition of trans…

Consensus guidelines for the detection of immunogenic cell death

2014

Apoptotic cells have long been considered as intrinsically tolerogenic or unable to elicit immune responses specific for dead cell-associated antigens. However, multiple stimuli can trigger a functionally peculiar type of apoptotic demise that does not go unnoticed by the adaptive arm of the immune system, which we named "immunogenic cell death" (ICD). ICD is preceded or accompanied by the emission of a series of immunostimulatory damage-associated molecular patterns (DAMPs) in a precise spatiotemporal configuration. Several anticancer agents that have been successfully employed in the clinic for decades, including various chemotherapeutics and radiotherapy, can elicit ICD. Moreover, defect…

Array-CGH and clinical characterization in a patient with subtelomeric 6p deletion without ocular dysgenesis

2011

Subtelomeric terminal 6p deletion has been recognized as a clinically identifiable syndrome including facial dysmorphism, malformation of the anterior eye chamber, hearing loss, heart defect and developmental delay. Genotype –phenotype correlations of previously published patients have been strongly suggested anterior eye segment anomalies as one of major malformation of the syndrome if the critical 6p25 region containing the FOXC 1 gene. In addition it has been hypothesized the presence in this region of one or more genes involved in hearing loss. We report on a case of terminal 6p deletion in a 47, XYY karyotype. Further characterization of the deletion with array comparative genome hybri…

Overexpression of STAT-1 by adenoviral gene transfer does not inhibit hepatitis B virus replication.

2006

Objectives Interferons are known to inhibit the replication of hepatitis B viruses (HBV) in several animal models in vitro and in vivo as well in humans. The STAT-1 protein plays a central role in the biological activity of both type I and type II interferons. The lack of functional STAT-1 renders cells and organisms susceptible to bacterial and viral infectious agents. We analysed whether the overexpression of STAT-1 protein enhances the biological interferon response and whether it elicits antiviral acitivity against HBV in vitro. Methods To achieve an efficient STAT-1 overexpression in primary liver cells and hepatoma cells, we generated a recombinant, replication-deficient adenovirus ex…