PubMed Central (PMC3 - NLM DTD)
(2,081,148 recursos)
Archive of life sciences journal literature at the U.S. National Institutes of Health (NIH), developed and managed by NIH's National Center for Biotechnology Information (NCBI) in the National Library of Medicine (NLM).
Mostrando recursos 41 - 60 de 951
41.
Evaluation for Hsp70 as a biomarker of effect of pollutants on the earthworm Lumbricus terrestris - Nadeau, Denis; Corneau, Sophie; Plante, Isabelle; Morrow, Geneviève; Tanguay, Robert M.
Induction of heat shock proteins (Hsps) is often associated with a cellular response to a harmful stress or to adverse life conditions. The main aims of the present study were (1) to assess if stress-induced Hsp70 could be used to monitor exposure of the earthworm species Lumbricus terrestris to various soil pollutants, (2) to assess the specificity of pollutants in their tissue targeting and in Hsp70 induction, and (3) to evaluate if dose-response relationships could be established and if the stress-response observed was specific. The midgut/intestinal tissues of L. terrestris are shown to express an inducible member of the Hsp70...
42.
Effects of heat shock, stannous chloride, and gallium nitrate on the rat inflammatory response - House, S.D.; Guidon, P.T.; Perdrizet, G.A.; Rewinski, M.; Kyriakos, R.; Bockman, R.S.; Mistry, T.; Gallagher, P.A.; Hightower, L.E.
Heat and a variety of other stressors cause mammalian cells and tissues to acquire cytoprotection. This transient state of altered cellular physiology is nonproliferative and antiapoptotic. In this study, male Wistar rats were stress conditioned with either stannous chloride or gallium nitrate, which have immunosuppressive effects in vivo and in vitro, or heat shock, the most intensively studied inducer of cytoprotection. The early stages of inflammation in response to topical suffusion of mesentery tissue with formyl-methionyl-leucyl-phenylalanine (FMLP) were monitored using intravital microscopy. Microvascular hemodynamics (venular diameter, red blood cell velocity [Vrbc], white blood cell [WBC] flux, and leukocyte-endothelial adhesion [LEA])...
43.
Role of priming stresses and Hsp70 in protection from ischemia-reperfusion injury in cardiac and skeletal muscle - Lepore, Diana A.; Knight, Kenneth R.; Anderson, Robin L.; Morrison, Wayne A.
Ischemia-reperfusion injury limits the survival of muscle involved in tissue trauma or transfers during microsurgical reconstruction. Priming stresses such as ischemic preconditioning or mild hyperthermia have frequently been associated with improved survival of ischemic-reperfused cardiac muscle, such protection coinciding with induction of the stress-related heat shock protein 70 (Hsp70). Little is known about the response of skeletal muscle to priming stresses. This review summarizes the current knowledge on the use of priming stresses as protective strategies against the consequences of ischemia-reperfusion in cardiac and skeletal muscle and the potential role of Hsp70.
44.
Metallothionein gene expression in peripheral lymphocytes from cadmium-exposed workers - Lu, Jian; Jin, Taiyi; Nordberg, Gunnar; Nordberg, Monica
Metallothionein (MT) plays an important role in the detoxification of cadmium.To investigate the usefulness of MT gene expression in peripheral blood lymphocytes (PBLs) as a biomarker of cadmium exposure and susceptibility, reverse transcriptasepolymerase chain reaction was used to measure the MT gene expression in PBLs from cadmium-exposed workers. Both basal and induced MT expressions were found to increase with increased blood cadmium (BCd) and urinary cadmium (UCd) levels. Both basal and induced MT expression levels were significantly correlated with the logarithm of BCd and the logarithm of UCd levels. The dose-response relationship between internal dose of cadmium and MT expression...
47.
Arabidopsis and the heat stress transcription factor world: how many heat stress transcription factors do we need? - Nover, Lutz; Bharti, Kapil; Döring, Pascal; Mishra, Shravan Kumar; Ganguli, Arnab; Scharf, Klaus-Dieter
Sequencing of the Arabidopsis genome revealed a unique complexity of the plant heat stress transcription factor (Hsf) family. By structural characteristics and phylogenetic comparison, the 21 representatives are assigned to 3 classes and 14 groups. Particularly striking is the finding of a new class of Hsfs (AtHsfC1) closely related to Hsf1 from rice and to Hsfs identified from frequently found expressed sequence tags of tomato, potato, barley, and soybean. Evidently, this new type of Hsf is well expressed in different plant tissues. Besides the DNA binding and oligomerization domains (HR-A/B region), we identified other functional modules of Arabidopsis Hsfs by...
48.
Arabidopsis thaliana type I and II chaperonins - Hill, Janet E.; Hemmingsen, Sean M.
An examination of the Arabidopsis thaliana genome sequence led to the identification of 29 predicted genes with the potential to encode members of the chaperonin family of chaperones (CPN60 and CCT), their associated cochaperonins, and the cytoplasmic chaperonin cofactor prefoldin. These comprise the first complete set of plant chaperonin protein sequences and indicate that the CPN family is more diverse than previously described. In addition to surprising sequence diversity within CPN subclasses, the genomic data also suggest the existence of previously undescribed family members, including a 10-kDa chloroplast cochaperonin. Consideration of the sequence data described in this review prompts questions...
49.
Genomic analysis of the Hsp70 superfamily in Arabidopsis thaliana - Lin, Bai-Ling; Wang, Jang-Shiun; Liu, Hung-Chi; Chen, Rung-Wu; Meyer, Yves; Barakat, Abdellalli; Delseny, Michel
The Arabidopsis genome contains at least 18 genes encoding members of the 70-kilodalton heat shock protein (Hsp70) family, 14 in the DnaK subfamily and 4 in the Hsp110/SSE subfamily. While the Hsp70s are highly conserved, a phylogenetic analysis including all members of this family in Arabidopsis and in yeast indicates the homology of Hsp70s in the subgroups, such as those predicted to localize in the same subcellular compartment and those similar to the mammalian Hsp110 and Grp170. Gene structure and genome organization suggest duplication in the origin of some genes. The Arabidopsis hsp70s exhibit distinct expression profiles; representative genes of...
50.
The J-domain proteins of Arabidopsis thaliana: an unexpectedly large and diverse family of chaperones - Miernyk, Jan A.
A total of 89 J-domain proteins were identified in the genome of the model flowering plant Arabidopsis thaliana. The deduced amino acid sequences of the J-domain proteins were analyzed for an assortment of structural features and motifs. Based on the results of sequence comparisons and structure and function predictions, 51 distinct families were identified. The families ranged in size from 1 to 6 members. Subcellular localizations of the A thaliana J-domain proteins were predicted; species were found in both the soluble and membrane compartments of all cellular organelles. Based on digital Northern analysis, the J-domain proteins could be separated into...
51.
Arabidopsis thaliana Hsp100 proteins: kith and kin - Agarwal, Manu; Katiyar-Agarwal, Surekha; Sahi, Chandan; Gallie, Daniel R.; Grover, Anil
Arabidopsis thaliana, the first plant for which the entire genome sequence is available, was also among the first plant species from which Hsp100 proteins were characterized. The Athsp101 complementary DNA (cDNA) corresponds to the gene identification At1g74310 in the Arabidopsis genome sequence. Analysis of the genome revealed 7 additional proteins that are variably homologous with At1g74310 throughout the entire amino acid sequence and significant similarities or identities in the signature sequences conserved among Hsp100 proteins. Although AtHsp101 is cytoplasmic, 5 of the 7 related proteins have predicted plastidial localization signals. This complete description of the AtHsp100 family sets the stage...
52.
The expanding family of Arabidopsis thaliana small heat stress proteins and a new family of proteins containing ?-crystallin domains (Acd proteins) - Scharf, Klaus-Dieter; Siddique, Masood; Vierling, Elizabeth
Comprehensive analysis of the Arabidopsis genome revealed a total of 13 sHsps belonging to 6 classes defined on the basis of their intracellular localization and sequence relatedness plus 6 ORFs encoding proteins distantly related to the cytosolic class CI or the plastidial class of sHsps. The complexity of the Arabidopsis sHsp family far exceeds that in any other organism investigated to date. Furthermore, we have identified a new family of ORFs encoding multidomain proteins that contain one or more regions with homology to the ACD (Acd proteins). The functions of the Acd proteins and the role of their ACDs remain...
53.
The Hsp90 family of proteins in Arabidopsis thaliana - Krishna, Priti; Gloor, Greg
The 90-kDa heat shock protein (Hsp90) is an essential molecular chaperone in eukaryotic cells, with key roles in the folding and activation of proteins involved in signal transduction and control of the cell cycle. A search for Hsp90 sequences in the Arabidopsis thaliana genome revealed that this family includes 7 members. The AtHsp90-1 through AtHsp90-4 proteins constitute the cytoplasmic subfamily, whereas the AtHsp90-5, AtHsp90-6, and AtHsp90-7 proteins are predicted to be within the plastidial, mitochondrial, and endoplasmic reticulum compartments, respectively. The deduced amino acid sequences of each of the cytoplasmic proteins contains the highly conserved C-terminal pentapeptide MEEVD. All of...
54.
Orthologs in Arabidopsis thaliana of the Hsp70 interacting protein Hip - Webb, Mary Alice; Cavaletto, John M.; Klanrit, Preekamol; Thompson, Gary A.
The Hsp70-interacting protein Hip binds to the adenosine triphosphatase domain of Hsp70, stabilizing it in the adenosine 5?-diphosphateligated conformation and promoting binding of target polypeptides. In mammalian cells, Hip is a component of the cytoplasmic chaperone heterocomplex that regulates signal transduction via interaction with hormone receptors and protein kinases. Analysis of the complete genome sequence of the model flowering plant Arabidopsis thaliana revealed 2 genes encoding Hip orthologs. The deduced sequence of AtHip-1 consists of 441 amino acid residues and is 42% identical to human Hip. AtHip-1 contains the same functional domains characterized in mammalian Hip, including an N-terminal dimerization...
55.
Heat shock protein 90 and the nuclear transport of progesterone receptor - Haverinen, Marjaana; Passinen, Satu; Syvälä, Heimo; Pasanen, Susanna; Manninen, Tommi; Tuohimaa, Pentti; Ylikomi, Timo
Steroid receptors exist as large oligomeric complexes in hypotonic cell extracts. In the present work, we studied the nuclear transport of the 2 major components of the oligomeric complex, the receptor itself and the heat shock protein 90 (Hsp90), by using different in vitro transport systems: digitonin permeabilized cells and purified nuclei. We demonstrate that the stabilized oligomeric complex of progesterone receptor (PR) cannot be transported into the nucleus and that unliganded PR salt dissociated from Hsp90 is transported into the nucleus. When nonstabilized PR oligomer was introduced into the nuclear transport system, the complex dissociated and the PR but...
56.
Stress induction of Bm1 RNA in silkworm larvae: SINEs, an unusual class of stress genes - Kimura, Richard H.; Choudary, Prabhakara V.; Stone, Koni K.; Schmid, Carl W.
This study surveys the induction of RNA polymerase III (Pol III)directed expression of short interspersed element (SINE) transcripts by various stresses in an animal model, silkworm larvae. Sublethal heat shock and exposure to several toxic compounds increase the level of Bm1 RNA, the silkworm SINE transcript, while also transiently increasing expression of a well-characterized stress-induced transcript, Hsp70 messenger RNA (mRNA). In certain cases, the Bm1 RNA response coincides with that of Hsp70 mRNA, but more often Bm1 RNA responds later in recovery. Baculovirus infection and exposure to certain toxic compounds increase Bm1 RNA but not Hsp70 mRNA, showing that SINE...
57.
Role of inducible heat shock protein 70 in radiation-induced cell death - Lee, Su-Jae; Choi, Sun-Ah; Lee, Kang-Hyun; Chung, Hee-Yong; Kim, Tae-Hwan; Cho, Chul-Koo; Lee, Yun-Sil
We previously demonstrated the protective effect of inducible heat shock protein 70 (Hsp70) against gamma radiation. Herein, we extend our studies on the possible role of Hsp70 to ionizing radiation-induced cell cycle regulation. The growth rate of inducible hsp70-transfected cells was 23 hours slower than that of control cells. Flow cytometric analysis of cells at G1 phase synchronized by serum starvation also showed the growth delay in the Hsp70-overexpressing cells. In addition, reduced cyclin D1 and Cdc2 levels and increased dephosphorylated phosphoretinoblastoma (pRb) were observed in inducible hsp70-transfected cells, which were probably responsible for the reduction of cell growth. To...
58.
Characterization and regulation of the major histocompatibility complexencoded proteins Hsp70-Hom and Hsp70-1/2 - Fourie, Anne M.; Peterson, Per A.; Yang, Young
Vertebrate cells contain at least 12 different genes for Hsp70 proteins, 3 of which are encoded in the major histocompatibility complex (MHC) class III region. In the human MHC, these are named Hsp70-1, -2, and -Hom. To characterize these proteins, we have determined their substrate binding specificity, their cellular and tissue distribution, and the regulation of their expression. We show for the first time (1) peptide binding specificity of Hsp70-Hom; (2) endogenous expression of Hsp70-Hom in human cell lines; (3) cytoplasmic location of Hsp70-Hom protein under basal conditions and concentration in the nucleus after heat shock; (4) unique RNA expression...
60.
The N-terminal adenosine triphosphate binding domain of Hsp90 is necessary and sufficient for interaction with estrogen receptor - Bouhouche-Chatelier, Ilham; Chadli, Ahmed; Catelli, Maria-Grazia
To understand how the molecular chaperone Hsp90 participates in conformational maturation of the estrogen receptor (ER), we analyzed the interaction of immobilized purified avian Hsp90 with mammalian cytosolic ER. Hsp90 was either immunoadsorbed to BF4 antibodySepharose or GST-Hsp90 fusion protein (GST.90) was adsorbed to glutathione-Sepharose. GST.90 was able to retain specifically ER, similarly to immunoadsorbed Hsp90. When cells were treated with estradiol and the hormone treatment was maintained during cell homogenization, binding, and washing steps, GST.90 still interacted efficiently with ER, suggesting that ER may form complexes with Hsp90 even after its activation by hormone and salt extraction from nuclei....
41.
