Abstract：
: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.
journal_name
J Cell Scijournal_title
Journal of cell scienceauthors
Niyaz Y,Zeiner M,Gehring Ukeywords:
subject
Has Abstractpub_date
2001-05-01 00:00:00pages
1839-45issue
Pt 10eissn
0021-9533issn
1477-9137journal_volume
114pub_type
杂志文章abstract：:Linear chains of five to hundreds of phosphates called polyphosphate are found in organisms ranging from bacteria to humans, but their function is poorly understood. In Dictyostelium discoideum, polyphosphate is used as a secreted signal that inhibits cytokinesis in an autocrine negative feedback loop. To elucidate ho...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.203372
更新日期：2017-07-15 00:00:00
abstract：:Microinjected GTP gamma S revealed three distinct steps in the exocytic transport of the temperature sensitive glycoprotein of vesicular stomatitis virus (ts-O45-G) from the ER to the cell surface in intact Vero cells. While COPII dependent export of ts-O45-G from the ER is blocked in cells injected with recombinant p...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1998-07-01 00:00:00
abstract：:Major histocompatibility complex class I (MHC-I) molecules signal infection or transformation by engaging receptors on T lymphocytes. The spatial organization of MHC-I on the plasma membranes is important for this engagement. We and others have shown that MHC-I molecules, like other membrane proteins, are not uniforml...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.187112
更新日期：2016-09-01 00:00:00
abstract：:The events responsible for repair of DNA interstrand cross-links in mammalian cells, the proteins involved and their interactions with each other are poorly understood. The present study demonstrates that the structural protein nonerythroid alpha spectrin (alphaSpIISigma*), present in normal human cell nuclei, plays a...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.00294
更新日期：2003-03-01 00:00:00
abstract：:Co-culture with glial cells and glia-conditioned media can induce blood-brain barrier properties in microvessel endothelial cells and protect against hypoxia-induced blood-brain barrier breakdown. We examined the effect of two types of glia-conditioned media on brain microvessel endothelial cell permeability and tight...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.00264
更新日期：2003-02-15 00:00:00
abstract：:The cross-striated muscle from the heart ventricle and the smooth penis retractor muscle of the freshwater snail Lymnaea stagnalis have been investigated by X-ray microanalysis to establish whether lanthanum can cross the plasma membrane, as has been reported by other investigators. Tissues were incubated in 1 mM ioni...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1985-04-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1993-10-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
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更新日期：2018-07-27 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.00295
更新日期：2003-03-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1981-06-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.119388
更新日期：2013-04-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1997-05-01 00:00:00
abstract：:Wound healing crucially relies on the mechanical activity of fibroblasts responding to TGFβ1 and to forces transmitted across focal adhesions. Integrin-linked kinase (ILK) is a central adapter recruited to integrin β1 tails in focal adhesions mediating the communication between cells and extracellular matrix. Here, we...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.063024
更新日期：2010-11-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1994-08-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1983-03-01 00:00:00
abstract：:The regulation of mitochondrial dynamics by the GTPase OPA1, which is located at the inner mitochondrial membrane, is crucial for adapting mitochondrial function and preserving cellular health. OPA1 governs the delicate balance between fusion and fission in the dynamic mitochondrial network. A disturbance of this bala...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
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更新日期：2016-06-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.065698
更新日期：2010-04-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.135947
更新日期：2014-09-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.205625
更新日期：2018-01-04 00:00:00
abstract：:Dictyostelium discoideum secretes a number of lysosomal enzymes during axenic growth and upon suspension in a low ionic strength, non-nutrient buffer (standard secretion conditions). These secretory characteristics have allowed us to identify 74 lysosomal enzyme secretory mutants generated by N-methyl-N'-nitro-N-nitro...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：
更新日期：1990-07-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.091991
更新日期：2011-11-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02446
更新日期：2005-07-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02275
更新日期：2005-05-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.149799
更新日期：2014-08-01 00:00:00
abstract：:The pericentriolar recycling endosome (RE) may be an alternative compartment through which some beta2-adrenergic receptors (beta2ARs) recycle from early endosomes to the cell surface during prolonged exposure to agonist. For the transferrin receptor, CXCR2, and the M4-muscarinic acetylcholine receptor, trafficking thr...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.01168
更新日期：2004-07-01 00:00:00
abstract：:Circadian rhythms regulate a wide variety of physiological and metabolic processes. The clock machinery comprises complex transcriptional-translational feedback loops that, through the action of specific transcription factors, modulate the expression of as many as 10% of cellular transcripts. This marked change in gen...
journal_title：Journal of cell science
pub_type： 杂志文章,评审
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更新日期：2010-11-15 00:00:00
abstract：:SNARE [soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein (SNAP) receptor] proteins control the membrane-fusion events of eukaryotic membrane-trafficking pathways. Specific vesicular and target SNAREs operate in specific trafficking routes, but the degree of specificity of SNARE functions is still elus...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.007948
更新日期：2007-09-15 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.03315
更新日期：2007-01-01 00:00:00
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journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.02993
更新日期：2006-07-01 00:00:00
abstract：:Human cytomegalovirus (HCMV) establishes life-long latent infection in hematopoietic progenitor cells and circulating monocytes in infected individuals. Myeloid differentiation coupled with immune dysregulation leads to viral reactivation, which can cause severe disease and mortality. Reactivation of latent virus requ...
journal_title：Journal of cell science
pub_type： 杂志文章
doi：10.1242/jcs.254268
更新日期：2021-01-25 00:00:00
