Search results for "rase"
showing 10 items of 4343 documents
The Yeast RNA Polymerase II-associated Factor Iwr1p Is Involved in the Basal and Regulated Transcription of Specific Genes
2009
RNA polymerase II (RNA pol II) is a multisubunit enzyme that requires many auxiliary factors for its activity. Over the years, these factors have been identified using both biochemical and genetic approaches. Recently, the systematic characterization of protein complexes by tandem affinity purification and mass spectroscopy has allowed the identification of new components of well established complexes, including the RNA pol II holoenzyme. Using this approach, a novel and highly conserved factor, Iwr1p, that physically interacts with most of the RNA pol II subunits has been described in yeast. Here we show that Iwr1p genetically interacts with components of the basal transcription machinery …
Gene expression is circular: factors for mRNA degradation also foster mRNA synthesis.
2013
SummaryMaintaining proper mRNA levels is a key aspect in the regulation of gene expression. The balance between mRNA synthesis and decay determines these levels. We demonstrate that most yeast mRNAs are degraded by the cytoplasmic 5′-to-3′ pathway (the “decaysome”), as proposed previously. Unexpectedly, the level of these mRNAs is highly robust to perturbations in this major pathway because defects in various decaysome components lead to transcription downregulation. Moreover, these components shuttle between the cytoplasm and the nucleus, in a manner dependent on proper mRNA degradation. In the nucleus, they associate with chromatin—preferentially ∼30 bp upstream of transcription start-sit…
Cadherin 23 is a component of the transient lateral links in the developing hair bundles of cochlear sensory cells
2005
AbstractCadherin 23 is required for normal development of the sensory hair bundle, and recent evidence suggests it is a component of the tip links, filamentous structures thought to gate the hair cells' mechano-electrical transducer channels. Antibodies against unique peptide epitopes were used to study the properties of cadherin 23 and its spatio-temporal expression patterns in developing cochlear hair cells. In the rat, intra- and extracellular domain epitopes are readily detected in the developing hair bundle between E18 and P5, and become progressively restricted to the distal tip of the hair bundle. From P13 onwards, these epitopes are no longer detected in hair bundles, but immunoreac…
Differential expression of Cryptosporidium parvum genes encoding sporozoite surface antigens in infected HCT-8 host cells.
2006
Intracellular replication of Cryptosporidium parvum (Apicomplexa) involves the generation of several asexual and sexual forms of the parasite. During the stage conversions, complex mechanisms lead to differential structural and functional properties of the parasite. These require a well tuned gene transcription machinery. For the first time the gene expression of four surface proteins of C. parvum sporozoites, CP15, CP17, P23, and GP900 were analysed in parallel by reverse transcription polymerase chain reaction. In addition, CP17 and P23 antigens were detected in infected host cells by immunofluorescence using antisera raised against recombinant forms of the proteins. The results show that…
Biomarker responses of the earthworm Aporrectodea tuberculata to copper and zinc exposure: differences between populations with and without earlier m…
2003
Biomarkers in the earthworm Aporrectodea tuberculata (Eisen) were measured to find out their possible induction under Cu and Zn exposure and differences in the responses between two populations with different exposure history. The biomarkers applied were concentration of metallothioneins (MT), and cytochrome P4501A (CYP1A) monooxygenase and glutathione-S-transferase (GST) activities. These were measured from earthworms sampled at three distances from a steel smelter in Finland and from the individuals from two populations, one with and another without earlier metal exposure, exposed to three combined Cu/Zn concentrations in the laboratory. In the field, MT concentration, and cytochrome CYP1…
Cytotoxic T lymphocytes define multiple peptide isoforms derived from the melanoma-associated antigen MART-1/Melan-A
1999
Peptides derived from the melanoma-associated MART-1/Melan-A antigen are currently implemented in immunotherapy for inducing or augmenting T-cell responses directed against peptides expressed by autologous tumor cells in HLA-A2+ patients with melanoma. Here, we describe the specificity of the T-cell clone SK29-FFM1.1, which secretes GM-CSF in response to a panel of synthetic MART-1/Melan-A-derived peptides, including the naturally presented ILTVILGVL32–40, but exhibits cytotoxicity and IFN-γ secretion exclusively to the MART-1/Melan-A derived peptide AAGIGILTV27–35. In addition, cytotoxic T-lymphocyte (CTL) clone SK29-FFM1.1 recognizes 3 different naturally processed and presented peptides …
Impaired Mast Cell-Driven Immune Responses in Mice Lacking the Transcription Factor NFATc2
2009
Abstract The three calcium-dependent factors NFATc1, c2, and c3 are expressed in cells of the immune system and play pivotal roles in modulating cellular activation. With regard to NFATc2, it was reported that NFATc2-deficient mice display increased immune responses in several models for infection and allergy in vivo. This led to the assumption that NFATc2 is involved in the maintenance of immune homeostasis. Using the synthetic TLR7 agonist imiquimod as an adjuvant in epicutaneous peptide immunization, we observed that both the inflammatory reaction and the peptide-specific CTL response are severely impaired in NFATc2-deficient mice. Detailed analyses revealed that early production of proi…
Cyclin-dependent kinase inhibitor p21 controls adult neural stem cell expansion by regulating Sox2 gene expression.
2012
Summary In the adult brain, continual neurogenesis of olfactory neurons is sustained by the existence of neural stem cells (NSCs) in the subependymal niche. Elimination of the cyclin-dependent kinase inhibitor 1A (p21) leads to premature exhaustion of the subependymal NSC pool, suggesting a relationship between cell cycle control and long-term self-renewal, but the molecular mechanisms underlying NSC maintenance by p21 remain unexplored. Here we identify a function of p21 in the direct regulation of the expression of pluripotency factor Sox2, a key regulator of the specification and maintenance of neural progenitors. We observe that p21 directly binds a Sox2 enhancer and negatively regulate…
Dynamic changes in the subcellular distribution of the tobacco ROS-producing enzyme RBOHD in response to the oomycete elicitor cryptogein.
2014
Highlight text The oomycete elicitor cryptogein triggers the relocation of RBOHD from intracellular compartments to the plasma membrane in tobacco cells. This suggests that intracellular trafficking is a potential determinant of RBOHD activity.
Poly (ADP-ribose) polymerase inhibition synergizes with the NF-κB inhibitor DHMEQ to kill hepatocellular carcinoma cells
2014
Poly (ADP-ribose) polymerase (PARP) enzymes play a key role in the cellular machinery responsible for DNA repair. Dehydroxymethylepoxyquinomicin (DHMEQ), a new inhibitor of NF-κB, induces oxidative stress and DNA damage. The effects of DHMEQ in combination with Olaparib (PARP inhibitor) were studied on hepatocellular carcinoma (HCC) cells. The DHMEQ-Olaparib combination synergistically inhibited cell viability, cell proliferation and colony formation of Hep3B, but had additive effects on Huh7 cells. The synergistic effects of the combination correlated with increased apoptosis, caspase 3/7 activity and PARP cleavage. There was an induction of an endoplasmic reticulum (ER) stress response wi…