Transcriptional activation by the human Hsp70-associating protein Hap50

2001 ◽  
Vol 114 (10) ◽  
pp. 1839-1845
Author(s):  
Y. Niyaz ◽  
M. Zeiner ◽  
U. Gehring
Keyword(s):  
Transcriptional Activation ◽  
Fluorescent Protein ◽  
Biological Effects ◽  
Cell Types ◽  
Mrna Stabilization ◽  
Activation Of Transcription ◽  
Enhanced Expression ◽  
Endogenous Genes ◽  
Green Fluorescent ◽  
Different Cell Types

We investigated human Hap50, the large isoform of the previously characterized Hsp70/Hsc70-associating protein Hap46, also called BAG-1, for effects on transcriptional activities. Overproduction by transient transfection led to enhanced expression of reporter gene constructs in various cell types using different promoters, suggesting independence of promoter type. Similarly, overexpression of Hap50 resulted in increased levels of poly(A)(+)mRNAs in HeLa, COS-7, 3T3 and HTC cells. Concomitantly, the expression of some selected endogenous genes, such as those coding for c-Jun and the glucocorticoid receptor, was enhanced significantly relative to actin. Nuclear runoff transcription assays using HeLa cells showed that the effect is caused by increased transcription rates rather than mRNA stabilization. Activation of transcription by Hap50 occurred at 37 degrees C and did not require prior thermal stress, as is the case for Hap46. In accordance with these biological effects, Hap50 is localized exclusively in the nuclear compartment of different cell types, whereas Hap46 is mostly cytoplasmic in unstressed cells, as revealed by use of fusion constructs with green fluorescent protein. High cellular levels of Hap50 were found to make cells less susceptible to adverse environmental effects such as heat stress. Our data suggest that Hap50 is a nuclear protein that acts in cells to increase the transcription of various genes.

EGFP expression in goat mammary epithelial cells

2006 ◽  
Vol 3 (1) ◽  
pp. 71-74 ◽  
Author(s):  
Zheng Yue-Mao ◽  
An Zhi-Xing ◽  
Peng Xin-Rong ◽  
Shi Yu-Qiang ◽  
Zhang Yong
Keyword(s):  
Epithelial Cells ◽  
Fluorescent Protein ◽  
Mammary Epithelial Cells ◽  
Cell Types ◽  
Mammary Epithelial ◽  
Egfp Expression ◽  
Green Fluorescent ◽  
Mammary Gland Cells ◽  
Different Cell Types ◽  
Goat Mammary Epithelial Cells

AbstractPrimary culture of goat mammary gland cells was achieved by outgrowth of migrating cells from fragments of tissue. The fibroblast and epithelial cells were purified according to their different sensitivity to trypsin and the characteristics of goat mammary epithelial cells were observed under a light microscope. The results showed that the purified goat mammary epithelial cells retained normal characteristics until the 15th passage. The purified mammary epithelial cells propagated and formed a dome-like structure that resembled a nipple and was called a ‘milk orb’. The mammary epithelial cells could produce and secrete milk. There were different cell types: the majority were short shuttle-like or polygons, resembling a beehive; while some were large, flat and round; and others were elongated. The enhanced green fluorescent protein (EGFP) gene was transferred successfully into the goat mammary epithelial cells using electrotransfection, and its expression was observed under a fluoroscope.

scholarly journals Bromodomain protein inhibition: a novel therapeutic strategy in rheumatic diseases

RMD Open ◽  
2018 ◽  
Vol 4 (2) ◽  
pp. e000744 ◽  
Author(s):  
Kerstin Klein
Keyword(s):  
Animal Models ◽  
Rheumatic Diseases ◽  
Transcriptional Activation ◽  
Therapeutic Strategy ◽  
Cell Types ◽  
Protein Inhibition ◽  
Different Cell Types ◽  
Novel Therapeutic

The reading of acetylation marks on histones by bromodomain (BRD) proteins is a key event in transcriptional activation. Small molecule inhibitors targeting bromodomain and extra-terminal (BET) proteins compete for binding to acetylated histones. They have strong anti-inflammatory properties and exhibit encouraging effects in different cell types in vitro and in animal models resembling rheumatic diseases in vivo. Furthermore, recent studies that focus on BRD proteins beyond BET family members are discussed.

scholarly journals A fate-mapping approach reveals the composite origin of the connecting tubule and alerts on “single-cell”-specific KO model of the distal nephron

2016 ◽  
Vol 311 (5) ◽  
pp. F901-F906 ◽  
Author(s):  
Francesco Trepiccione ◽  
Christelle Soukaseum ◽  
Anna Iervolino ◽  
Federica Petrillo ◽  
Miriam Zacchia ◽  
...  
Keyword(s):  
Single Cell ◽  
Kidney Development ◽  
Fluorescent Protein ◽  
Collecting Duct ◽  
Yellow Fluorescent Protein ◽  
Cell Types ◽  
Intercalated Cells ◽  
Distal Nephron ◽  
Principal Cells ◽  
Different Cell Types

The distal nephron is a heterogeneous part of the nephron composed by six different cell types, forming the epithelium of the distal convoluted (DCT), connecting, and collecting duct. To dissect the function of these cells, knockout models specific for their unique cell marker have been created. However, since this part of the nephron develops at the border between the ureteric bud and the metanephric mesenchyme, the specificity of the single cell markers has been recently questioned. Here, by mapping the fate of the aquaporin 2 (AQP2) and Na+-Cl−cotransporter (NCC)-positive cells using transgenic mouse lines expressing the yellow fluorescent protein fluorescent marker, we showed that the origin of the distal nephron is extremely composite. Indeed, AQP2-expressing precursor results give rise not only to the principal cells, but also to some of the A- and B-type intercalated cells and even to cells of the DCT. On the other hand, some principal cells and B-type intercalated cells can develop from NCC-expressing precursors. In conclusion, these results demonstrate that the origin of different cell types in the distal nephron is not as clearly defined as originally thought. Importantly, they highlight the fact that knocking out a gene encoding for a selective functional marker in the adult does not guarantee cell specificity during the overall kidney development. Tools allowing not only cell-specific but also time-controlled recombination will be useful in this sense.

scholarly journals Knockdown of tyrosine hydroxylase in the nucleus of the solitary tract reduces elevated blood pressure during chronic intermittent hypoxia

2013 ◽  
Vol 305 (9) ◽  
pp. R1031-R1039 ◽  
Author(s):  
Chandra Sekhar Bathina ◽  
Anuradha Rajulapati ◽  
Michelle Franzke ◽  
Kenta Yamamoto ◽  
J. Thomas Cunningham ◽  
...  
Keyword(s):  
Tyrosine Hydroxylase ◽  
Transcriptional Activation ◽  
Intermittent Hypoxia ◽  
Fluorescent Protein ◽  
Nucleus Tractus Solitarius ◽  
Cardiovascular Responses ◽  
Ventrolateral Medulla ◽  
Chronic Intermittent Hypoxia ◽  
Sprague Dawley ◽  
Green Fluorescent

Noradrenergic A2 neurons in nucleus tractus solitarius (NTS) respond to stressors such as hypoxia. We hypothesize that tyrosine hydroxylase (TH) knockdown in NTS reduces cardiovascular responses to chronic intermittent hypoxia (CIH), a model of the arterial hypoxemia observed during sleep apnea in humans. Adult male Sprague-Dawley rats were implanted with radiotelemetry transmitters and adeno-associated viral constructs with green fluorescent protein (GFP) reporter having either short hairpin RNA (shRNA) for TH or scrambled virus (scRNA) were injected into caudal NTS. Virus-injected rats were exposed to 7 days of CIH (alternating periods of 10% O2 and of 21% O2 from 8 AM to 4 PM; from 4 PM to 8 AM rats were exposed to 21% O2). CIH increased mean arterial pressure (MAP) and heart rate (HR) during the day in both the scRNA ( n = 14, P < 0.001 MAP and HR) and shRNA ( n = 13, P < 0.001 MAP and HR) groups. During the night, MAP and HR remained elevated in the scRNA rats ( P < 0.001 MAP and HR) but not in the shRNA group. TH immunoreactivity and protein were reduced in the shRNA group. FosB/ΔFosB immunoreactivity was decreased in paraventricular nucleus (PVN) of shRNA group ( P < 0.001). However, the shRNA group did not show any change in the FosB/ΔFosB immunoreactivity in the rostral ventrolateral medulla. Exposure to CIH increased MAP which persisted beyond the period of exposure to CIH. Knockdown of TH in the NTS reduced this CIH-induced persistent increase in MAP and reduced the transcriptional activation of PVN. This indicates that NTS A2 neurons play a role in the cardiovascular responses to CIH.

scholarly journals Differential Regulation of Human Interferon A Gene Expression by Interferon Regulatory Factors 3 and 7

2009 ◽  
Vol 29 (12) ◽  
pp. 3435-3450 ◽  
Author(s):  
Pierre Génin ◽  
Rongtuan Lin ◽  
John Hiscott ◽  
Ahmet Civas
Keyword(s):  
Gene Expression ◽  
Differential Expression ◽  
Transcriptional Activation ◽  
Cell Types ◽  
Inhibitory Effect ◽  
Human Interferon ◽  
Gene Promoters ◽  
Nucleotide Substitutions ◽  
D Modules ◽  
Different Cell Types

ABSTRACT Differential expression of the human interferon A (IFN-A) gene cluster is modulated following paramyxovirus infection by the relative amounts of active interferon regulatory factor 3 (IRF-3) and IRF-7. IRF-3 expression activates predominantly IFN-A1 and IFN-B, while IRF-7 expression induces multiple IFN-A genes. IFN-A1 gene expression is dependent on three promoter proximal IRF elements (B, C, and D modules, located at positions −98 to −45 relative to the mRNA start site). IRF-3 binds the C module of IFN-A1, while other IFN-A gene promoters are responsive to the binding of IRF-7 to the B and D modules. Maximal expression of IFN-A1 is observed with complete occupancy of the three modules in the presence of IRF-7. Nucleotide substitutions in the C modules of other IFN-A genes disrupt IRF-3-mediated transcription, whereas a G/A substitution in the D modules enhances IRF7-mediated expression. IRF-3 exerts dual effects on IFN-A gene expression, as follows: a synergistic effect with IRF-7 on IFN-A1 expression and an inhibitory effect on other IFN-A gene promoters. Chromatin immunoprecipitation experiments reveal that transient binding of both IRF-3 and IRF-7, accompanied by CBP/p300 recruitment to the endogenous IFN-A gene promoters, is associated with transcriptional activation, whereas a biphasic recruitment of IRF-3 and CBP/p300 represses IFN-A gene expression. This regulatory mechanism contributes to differential expression of IFN-A genes and may be critical for alpha interferon production in different cell types by RIG-I-dependent signals, leading to innate antiviral immune responses.

scholarly journals Molecular Mechanism of the Inhibition of Estradiol-Induced Endometrial Epithelial Cell Proliferation by Clomiphene Citrate

Endocrinology ◽  
2010 ◽  
Vol 151 (1) ◽  
pp. 394-405 ◽  
Author(s):  
Mitsuyoshi Amita ◽  
Toshifumi Takahashi ◽  
Seiji Tsutsumi ◽  
Tsuyoshi Ohta ◽  
Keiko Takata ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Epithelial Cell ◽  
Transcriptional Activation ◽  
Molecular Mechanisms ◽  
Fluorescent Protein ◽  
Clomiphene Citrate ◽  
Immunofluorescence Assay ◽  
Epithelial Cell Proliferation ◽  
Endometrial Epithelial Cell ◽  
Green Fluorescent

Abstract We examined the molecular mechanisms of the antiestrogenic effects of clomiphene citrate (CC) in the endometrium using two types of cell lines, Ishikawa and EM-E6/E7/hTERT cells. CC or ICI182780 inhibited 17β-estradiol (E2)-induced endometrial cell proliferation and transcriptional activation of the estrogen response element (ERE) gene. We directly visualized the ligand-estrogen receptor (ER)α interaction using green fluorescent protein (GFP)-tagged ERα in a single living cell. Whereas E2 changed the nuclear localization of GFP-ERα to a punctate distribution within 5 min, CC or ICI182780 changed the slower and less mobilization of GFP-ERα compared with E2. Pretreatment with CC or ICI182780 partly prevented the E2-induced nuclear redistribution of GFP-ERα. Fluorescence recovery after photobleaching revealed that GFP-ERα mobility treated with E2 was more rapid than that treated by CC or ICI182780. As coactivator recruitment to the ER is essential for ER-dependent transcription, we examined the interaction between ERα and steroid receptor coactivator-1 (SRC-1). The complex formation between ERα and SRC-1 was significantly increased by E2 but was prevented in the presence of CC or ICI182780 by coimmunoprecipitation. Moreover, the E2-induced colocalization of GFP-ERα and SRC-1 was prevented in the presence of CC or ICI182780 according to an immunofluorescence assay. We also observed that the reduction of SRC-1 using small interfering RNA for SRC-1 resulted in the inhibition of E2-induced cell proliferation and transcriptional activation of the ERE gene. Collectively, these results suggest that CC may inhibit E2-induced endometrial epithelial cell proliferation and ERE transactivation by inhibiting the recruitment of SRC-1 to ERα.

scholarly journals Global Analysis of Cell Type-Specific Gene Expression

2003 ◽  
Vol 4 (2) ◽  
pp. 208-215 ◽  
Author(s):  
David W. Galbraith
Keyword(s):  
Gene Expression ◽  
Fluorescent Protein ◽  
Global Analysis ◽  
Expression Patterns ◽  
Three Dimensional ◽  
Global Gene Expression ◽  
Cell Types ◽  
Reasonable Assumption ◽  
Specific Gene ◽  
Different Cell Types

The tissues and organs of multicellular eukaryotes are frequently observed to comprise complex three-dimensional interspersions of different cell types. It is a reasonable assumption that different global patterns of gene expression are found within these different cell types. This review outlines general experimental strategies designed to characterize these global gene expression patterns, based on a combination of methods of transgenic fluorescent protein (FP) expression and targeting, of flow cytometry and sorting and of high-throughput gene expression analysis.

scholarly journals Relaxed Repression of Herpes Simplex Virus Type 1 Genomes in Murine Trigeminal Neurons

2007 ◽  
Vol 81 (22) ◽  
pp. 12394-12405 ◽  
Author(s):  
Tracy Terry-Allison ◽  
Colton A. Smith ◽  
Neal A. DeLuca
Keyword(s):  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Fluorescent Protein ◽  
Cultured Cells ◽  
Trichostatin A ◽  
Cell Types ◽  
Immediate Early ◽  
Green Fluorescent ◽  
Simplex Virus

ABSTRACT The expression of herpes simplex virus (HSV) genomes in the absence of viral regulatory proteins in sensory neurons is poorly understood. Previously, our group reported an HSV immediate early (IE) mutant (d109) unable to express any of the five IE genes and encoding a model human cytomegalovirus immediate early promoter-green fluorescent protein (GFP) transgene. In cultured cells, GFP expressed from this mutant was observed in only a subset of infected cells. The subset exhibited cell type dependence, as the fractions of GFP-expressing cells varied widely among the cell types examined. Herein, we characterize this mutant in murine embryonic trigeminal ganglion (TG) cultures. We found that d109 was nontoxic to neural cultures and persisted in the cultures throughout their life spans. Unlike with some of the cultured cell lines and strains, expression of the GFP transgene was observed in a surprisingly large subset of neurons. However, very few nonneuronal cells expressed GFP. The abilities of ICP0 and an inhibitor of histone deacetylase, trichostatin A (TSA), to activate GFP expression from nonexpressing cells were also compared. The provision of ICP0 by infection with d105 reactivated quiescent genomes in nearly every cell, whereas reactivation by TSA was much more limited and restricted to the previously nonexpressing neurons. Moreover, we found that d109, which does not express ICP0, consistently reactivated HSV type 1 (KOS) in latently infected adult TG cultures. These results suggest that the state of persisting HSV genomes in some TG neurons may be more dynamic and more easily activated than has been observed with nonneuronal cells.

scholarly journals A PDZ-containing Scaffold Related to the Dystrophin Complex at the Basolateral Membrane of Epithelial Cells

1999 ◽  
Vol 145 (2) ◽  
pp. 391-402 ◽  
Author(s):  
Amy M. Kachinsky ◽  
Stanley C. Froehner ◽  
Sharon L. Milgram
Keyword(s):  
Skeletal Muscle ◽  
Fluorescent Protein ◽  
Protein Complexes ◽  
Basolateral Membrane ◽  
Pdz Domain ◽  
Cell Types ◽  
Protein Domain ◽  
Ph Domain ◽  
Green Fluorescent ◽  
Dystrophin Complex

Membrane scaffolding complexes are key features of many cell types, serving as specialized links between the extracellular matrix and the actin cytoskeleton. An important scaffold in skeletal muscle is the dystrophin-associated protein complex. One of the proteins bound directly to dystrophin is syntrophin, a modular protein comprised entirely of interaction motifs, including PDZ (protein domain named for PSD-95, discs large, ZO-1) and pleckstrin homology (PH) domains. In skeletal muscle, the syntrophin PDZ domain recruits sodium channels and signaling molecules, such as neuronal nitric oxide synthase, to the dystrophin complex. In epithelia, we identified a variation of the dystrophin complex, in which syntrophin, and the dystrophin homologues, utrophin and dystrobrevin, are restricted to the basolateral membrane. We used exogenously expressed green fluorescent protein (GFP)-tagged fusion proteins to determine which domains of syntrophin are responsible for its polarized localization. GFP-tagged full-length syntrophin targeted to the basolateral membrane, but individual domains remained in the cytoplasm. In contrast, the second PH domain tandemly linked to a highly conserved, COOH-terminal region was sufficient for basolateral membrane targeting and association with utrophin. The results suggest an interaction between syntrophin and utrophin that leaves the PDZ domain of syntrophin available to recruit additional proteins to the epithelial basolateral membrane. The assembly of multiprotein signaling complexes at sites of membrane specialization may be a widespread function of dystrophin-related protein complexes.

scholarly journals Nucleocytoplasmic transport in human astrocytes: decreased nuclear uptake of the HIV Rev shuttle protein

2001 ◽  
Vol 114 (9) ◽  
pp. 1717-1729
Author(s):  
M. Neumann ◽  
E. Afonina ◽  
F. Ceccherini-Silberstein ◽  
S. Schlicht ◽  
V. Erfle ◽  
...  
Keyword(s):  
Fluorescent Protein ◽  
Virus Production ◽  
Time Lapse ◽  
Cell Types ◽  
Nucleocytoplasmic Transport ◽  
Nucleocytoplasmic Trafficking ◽  
Nuclear Uptake ◽  
Strong Shift ◽  
Human Astrocytes ◽  
Green Fluorescent

Astrocytes are cellular targets for the human immunodeficiency virus (HIV) that limit virus production, owing, at least in part, to the diminished functionality of the viral post-transcriptional stimulatory factor Rev. To understand the trafficking process in astrocytes, we compared nucleocytoplasmic transport of Rev and various proteins with well-characterized nucleocytoplasmic transport features in human astrocytes and control cells (HeLa). Localization and trafficking characteristics of several cellular and viral proteins, as well as nuclear trafficking of classical peptide signals upon microinjection were similar in both cell types, indicating maintenance of general features of nucleocytoplasmic transport in astrocytes. Quantification of fluorescence in living cells expressing Rev fused to green fluorescent protein (GFP) indicated a strong shift in intracellular distribution of Rev in astrocytes, with 50–70% of Rev in the cytoplasm, whereas the cytoplasmic proportion of Rev in HeLa cells is around 10%. The dynamics of nucleocytoplasmic trafficking of Rev were compared in astrocytes and Rev-permissive cells by monitoring migration of Rev-GFP in cell fusions using highly sensitive time-lapse imaging. Nuclear uptake of Rev was dramatically retarded in homo-polykaryons of astrocytes compared with control cells. Diminished nuclear uptake of Rev was also observed in hetero-polykaryons of Rev-permissive cells and astrocytes. These results indicate that astrocytes contain a cytoplasmic activity that interferes with nuclear uptake of Rev. Our studies suggest a model in which Rev is prevented from functioning efficiently in astrocytes by specific alterations of its nucleocytoplasmic trafficking properties. http://www.biologists.com/JCS/movies/jcs1709.html

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