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1.
Histone deacetylase controls adult stem cell aging by balancing the expression of polycomb genes and jumonji domain containing 3 总被引:1,自引:1,他引:0
Ji-Won Jung Seunghee Lee Min-Soo Seo Sang-Bum Park Andreas Kurtz Soo-Kyung Kang Kyung-Sun Kang 《Cellular and molecular life sciences : CMLS》2010,67(7):1165-1176
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3.
Kaushal S Ghosh S Sharma N Sanyal SN Majumdar S 《Cellular and molecular life sciences : CMLS》2001,58(14):2098-2107
A 36-kDa phospholipid transfer protein (PLT-PR), which preferentially transfers phosphatidyl choline (PC) compared to phosphatidyl inositol (PI), was purified 827-fold
from rabbit lung homogenate. Incorporation of cholesterol in unilamellar vesicles reduced the PC transfer activity of PLTPR. Dipalmitoyl phosphatidyl choline uptake by alveolar type II cells was increased in the presence of the protein, and further
enhanced in the presence of surfactant liposomes. However, a decrease in uptake was noted with cholesterol in host membranes.
Incorporation of PI into host membranes had a low stimulatory effect on the process. All these effects were more pronounced
in adult type II cells compared to premature, term and 3-day-old pups.
Received 12 September 2001; accepted 11 October 2001 相似文献
4.
5.
H. Mueller 《Cellular and molecular life sciences : CMLS》1998,54(12):1291-1298
The discovery and cloning of the cytokine tumor necrosis factor α (TNF) gave rise to new hopes for a significant victory in the war against cancer. Preclinical in vitro studies in cell cultures
and in vivo studies in animal models demonstrated the antitumor capacities of TNF. Although clinical studies were largely
made possible by the availability of recombinant TNF, phase I and II clinical trials showed very quickly that the systemic
administration of TNF induced severe side effects mainly due to its pleiotropic action on immunocompetent cells. The clinical
manifestations of the side effects were similar to those observed during a severe infection and inflammation. Very recently,
lessons from these clinical studies yielded refined approaches whereby the toxicity of TNF is limited through local administration,
a combination with other therapeutic regimens and targeted gene therapy. These new approaches are slated for larger clinical
trials and in the near future might demonstrate the limited but powerful usefulness of TNF as an antineoplastic agent for
different types of cancer.
Received 7 September 1998; received after revision 15 October 1998; accepted 15 October 1998 相似文献
6.
We report that histones H2A and H2B possess gonadotrophin-releasing activity in vitro and assess the signal transduction
pathways involved in these effects. Perifused and incubated rat anterior pituitary (AP) cells were used, and luteinizing hormone
(LH) and follicle stimulating hormone (FSH) were measured by RIA. Perifusion of cells with histone H2A (30 μM) or histone
H2B (30 μM), markedly stimulated LH release but failed to elicit any FSH response. Cells incubated with 6 or 30 μM histone
H2A showed a dose- and time-dependent stimulatory effect on both LH and FSH release which was blocked by 1 μM peptide MB35,
an 86–120 amino acid fragment of histone H2A. Incubation of pituitary cells with gonadotrophin-releasing hormone (GnRH) and
histones H2A or H2B showed a stimulatory effect on LH and FSH release which was similar to the sum of the separate effects.
Trifluoperazine, as well as ethylene glycol bis(b-aminoethyl ether) N,N,N′,N′-tetraacetic acid (EGTA), alone or in the presence
of the calcium ionophore A23187, significantly reduced the response of AP cells to histones. Various cyclic adenosine monophosphate
(cAMP) enhancers had no effect on histone-stimulated release of gonadotrophins in incubated AP cells. Our results confirm
previous evidence that histones may act as hypophysiotrophic signals. Calcium- and diacylglycerol-associated pathways, but
not cAMP, appear to participate in these effects.
Received 11 August 1997; received after revision 20 January 1998; accepted 26 January 1998 相似文献
7.
Novel regulation and function of Src tyrosine kinase 总被引:4,自引:0,他引:4
Src tyrosine kinase is a critical signal transducer that modulates a wide variety of cellular functions. Misregulation of
Src leads to cell transformation and cancer. Heterotrimeric guanine-nucleotide-binding proteins (G proteins) are another group
of signaling molecules that transduce signals from cell-surface receptors to generate physiological responses. Recently, it
was discovered that Gαs and Gαi could directly stimulate Src family tyrosine kinase activity. This novel regulation of Src
tyrosine kinase by G proteins provides insights into the adenylyl cyclase-independent signaling mechanisms involved in ligand-induced
receptor desensitization, internalization and other physiological processes.
Received 17 August 2001; received after revision 22 October 2001; accepted 24 October 2001 相似文献
8.
Thyroid hormone controls carnitine status through modifications of γ-butyrobetaine hydroxylase activity and gene expression 总被引:1,自引:0,他引:1
Galland S Georges B Le Borgne F Conductier G Dias JV Demarquoy J 《Cellular and molecular life sciences : CMLS》2002,59(3):540-545
The carnitine system plays a key role in β-oxidation of long-chain fatty acids by permitting their transport into the mitochondrial
matrix. The effects of hypothyroidism and hyperthyroidism were studied on γ-butyrobetaine hydroxylase (BBH), the enzyme responsible
for carnitine biosynthesis in the rat. In rat liver, BBH activity was decreased in the hypothyroid state and increased in
hyperthyroid animals. The modifications in BBH activity correlated with changes in the enzyme Vmax values. These changes were
shown to be related to hepatic BBH mRNA abundance. Thyroid hormones are known to interact with lipid metabolism, in particular
by increasing long-chain fatty acid oxidation through activation of carnitine-dependent fatty acid import into mitochondria.
Our study showed that thyroid hormones also increased carnitine bioavailability.
Received 23 October 2001; received after revision 11 January 2002; accepted 15 January 2002 相似文献
9.
The intracellular signaling pathways mediating the nuclear exclusion of the androgen receptor (AR) by melatonin were evaluated
in PC3 cells stably transfected with the AR. The melatonin-induced nuclear exclusion of the AR by melatonin (100 nM, 3 h)
was blocked by LY 83583 (an inhibitor of guanylyl cyclases). 8-Bromo-cGMP (a cell-permeable cGMP analog), mimicked the effect
of melatonin, as did ionomycin (a calcium ionophore) and PMA [an activator of protein kinase C (PKC)], and their effects were
blocked by GF-109203X (a selective PKC inhibitor). BAPTA (an intracellular calcium chelator) blocked the effects of melatonin
and 8-bromo-cGMP but not of PMA. Inhibition or activation of the protein kinase A pathway did not affect basal or melatonin-mediated
AR localization. We conclude that the melatonin-mediated rise in cGMP elicits AR nuclear exclusion via a pathway involving
increased intracellular calcium and PKC activation. These results define a novel signaling pathway that regulates AR localization
and androgen responses in target cells.
Received 31 July 2001; received after revision 18 September 2001; accepted 30 October 2001 相似文献
10.
Signalling roles of mammalian phospholipase D1 and D2 总被引:11,自引:0,他引:11
S. Cockcroft 《Cellular and molecular life sciences : CMLS》2001,58(11):1674-1687
Phospholipase D (PLD) catalyses the hydrolysis of phosphatidylcholine to generate the lipid second messenger, phosphatidate
(PA) and choline. PLD activity in mammalian cells is low and is transiently stimulated upon activation by G-protein-coupled
and receptor tyrosine kinase cell surface receptors. Two mammalian PLD enzymes (PLD1 and PLD2) have been cloned and their
intracellular regulators identified as ARF and Rho proteins, protein kinase Cα as well as the lipid, phosphatidylinositol
[4, 5] bisphosphate (PIP2). I discuss the regulation of these enzymes by cell surface receptors, their cellular localisation and the potential function
of PA as a second messenger. Evidence is presented for a role of PA in regulating the lipid kinase activity of PIP 5-kinase,
an enzyme that synthesises PIP2. A signalling role of phospholipase D via PA and indirectly via PIP2 in regulating membrane traffic and actin dynamics is indicated by the available data.
Received 25 April 2001; received after revision 15 June 2001; accepted 15 June 2001 相似文献
11.
Di Francesco AM Ruggiero A Riccardi R 《Cellular and molecular life sciences : CMLS》2002,59(11):1914-1927
Oxaliplatin (Eloxatine) is a third-generation platinum compound which has shown a wide antitumour effect both in vitro and
in vivo, a better safety profile than cisplatin and a lack of cross-resistance with cisplatin and carboplatin. In this scenario,
oxaliplatin may represent an innovative and challenging drug extending the antitumour activity in diseases such as gastrointestinal
cancer that are not usually sensitive to these coordination complexes. Oxaliplatin has a non-hydrolysable diaminocyclohexane
(DACH) carrier ligand which is maintained in the final cytotoxic metabolites of the drug. Like cisplatin, oxaliplatin targets
DNA producing mainly 1,2-GG intrastrand cross-links. The cellular and molecular aspects of the mechanism of action of oxaliplatin
have not yet been fully elucidated. However, the intrinsic chemical and steric characteristics of the DACH-platinum adducts
appear to contribute to the lack of cross-resistance with cisplatin. To date, mismatch repair and replicative bypass appear
to be the processes most likely involved in differentiating the molecular responses to these agents.
Received 15 March 2002; received after revision 13 May 2002; accepted 21 May 2002
RID="*"
ID="*"Corresponding author. 相似文献
12.
Di Felice V David S Cappello F Farina F Zummo G 《Cellular and molecular life sciences : CMLS》2005,62(1):4-9
Heat shock protein 60 (HSP60) plays an important role in the protein folding of prokaryotic and eukaryotic cells. Most of the papers published on chlamydial HSP60 concern its role in immune response during infection. In the last decade, exposure to Chlamydia trachomatis has been consistently associated with the development of cervical and ovarian cancer. Moreover, it has been suggested that chlamydial HSP60 may have an anti-apoptotic effect during persistent infection. We hypothesize that the accumulation of exogenous chlamydial HSP60 in the cytoplasm of actively replicating eukaryotic cells may interfere with the regulation of the apoptotic pathway. The concomitant expression of viral oncoproteins and/or the presence of mutations may lead to the ability to survive apoptotic stimuli, loss of replicative senescence, uncontrolled proliferation and, finally neoplastic transformation.Received 15 August 2004; received after revision 1 October 2004; accepted 7 October 2004 相似文献
13.
Culture in low levels of oxygen enhances in vitro proliferation potential of satellite cells from old skeletal muscles 总被引:4,自引:0,他引:4
Chakravarthy MV Spangenburg EE Booth FW 《Cellular and molecular life sciences : CMLS》2001,58(8):1150-1158
The proliferation ability of satellite cells (considered the 'stem cells' of mature myofibers) declines with increasing age
when cultured under standard cell culture conditions of 21% oxygen. However, actual oxygen levels in the intact myofiber in
vivo are an order of magnitude lower. No studies to date have addressed the issue of whether culturing satellite cells from
old muscles under more 'physiologic' conditions would enhance their proliferation and/or differentiation ability. Therefore,
we analyzed satellite cells derived from 31-month-old rats in standard cultures with 21% O2 and in lowered (∼3%) O2. Under the lowered O2 conditions, we noted a remarkable increase in the percentage of large-sized colonies, activation of cell cycle progression
factors, phosphorylation of Akt, and downregulation of the cell cycle inhibitor p27Kip1. These data suggest that lower O2 levels provide a milieu that stimulates proliferation by allowing continued cell cycle progression, to result ultimately
in the enhanced in vitro replicative life span of the old satellite cells. Such a method therefore provides an improved means
for the ex vivo generation of progenitor satellite cell populations for potential therapeutic stem cell transplantation.
Received 20 April 2001; received after revision 28 May 2001; accepted 31 May 2001 相似文献
14.
The activity of poly(ADP-Rib) polymerase is enhanced in the presence of spermine and spermidine. Among the adenosine-like antibiotics tested, only formycin B and showdomycin cause an inhibition of the enzyme, which is competitive to NAD. The activity of poly(ADP-Rib) polymerase is not reduced by rifamycin, alpha-amanitin and 2-phenylethanol. 相似文献
15.
van den Elzen R Guillén J Ruiz-del-Valle V Allende LM Lowy E Zamora J Arnaiz-Villena A 《Cellular and molecular life sciences : CMLS》2001,58(14):2117-2128
South American siskin radiation was studied by both mitochondrial cytochrome b (mt cyt b) DNA sequencing and homologous phenotypic
characters; the latter were coded separately according to sex. Mixed phenetic and molecular (total evidence) dendrograms were
constructed and the corresponding analyses suggest that speciation started in the South American siskin group with a north
to south separation (Carduelis notata/C. barbata) along the Andean spine. A second split may have taken place around the Peruvian Andean mountains, corresponding to the present
distribution pattern of C. olivacea. The most recent speciation events seem to have occurred in three sister species pairs: (i) C. xanthogastra/C. atrata, (ii) C. magellanica/C. yarrellii, (iii) C. cucullata/C. crassirostris. Accumulation of consistent characters in both morphological and molecular data at the basal nodes of the dendrograms indicate
that speciation events occurred within a short period of time. Our data also suggest that speciation probably occurred by
sexual selection through female mating choice in this radiation. Additionally, studies of variable amino acid residues in
the mt cyt b molecule show that the three variable amino acids found are placed in the mitochondrial transmembrane region,
which is also part of the hypervariable region in mammals. Each of the three amino acid changes occur in each of the three
postulated evolutionary groups.
Received 11 September 2001; received after revision 12 October 2001; accepted 15 October 2001 相似文献
16.
Prosperi-Meys C Wouters J Galleni M Lamotte-Brasseur J 《Cellular and molecular life sciences : CMLS》2001,58(14):2136-2143
Increased resistance to β-lactam antibiotics is mainly due to β-lactamases whose production by pathogenic bacteria makes their broad activity spectrum
especially frightening. X-ray structures of several zinc β-lactamases have revealed the coordination of the two metal ions, but their mode of action remains unclear. Geometry optimisation
of stable complexes along the reaction pathway of benzylpenicillin hydrolysis highlighted a proton shuttle occurring from
D120 of the Bacillus cereus β-lactamase to the β-lactam nitrogen via Zn2 which is central to the network. First, the Zn1 ion has a structural role maintaining Zn-bound waters,
WAT1 and WAT2, either directly or through the Zn1 tetrahedrally coordinated histidine ligands. The Zn2 ion has a more catalytic
role, stabilising the tetrahedral intermediate, accepting the β-lactam nitrogen atom as a ligand. The role of Zn2 and the flexibility in the coordination geometry of both Zn ions is of
crucial importance for catalysis.
Received 14 August 2001; received after revision 19 October 2001; accepted 30 October 2001 相似文献
17.
Eun Seong Hwang Gyesoon Yoon Hyun Tae Kang 《Cellular and molecular life sciences : CMLS》2009,66(15):2503-2524
Various intracellular organelles, such as lysosomes, mitochondria, nuclei, and cytoskeletons, change during replicative senescence,
but the utility of these changes as general markers of senescence and their significance with respect to functional alterations
have not been comprehensively reviewed. Furthermore, the relevance of these alterations to cellular and functional changes
in aging animals is poorly understood. In this paper, we review the studies that report these senescence-associated changes
in various aging cells and their underlying mechanisms. Changes associated with lysosomes and mitochondria are found not only
in cells undergoing replicative or induced senescence but also in postmitotic cells isolated from aged organisms. In contrast,
other changes occur mainly in cells undergoing in vitro senescence. Comparison of age-related changes and their underlying
mechanisms in in vitro senescent cells and aged postmitotic cells would reveal the relevance of replicative senescence to
the physiological processes occurring in postmitotic cells as individuals age. 相似文献
18.
Arginase expression in peritoneal macrophages and increase in circulating polyamine levels in mice infected with Schistosoma mansoni 总被引:5,自引:0,他引:5
Abdallahi OM Bensalem H Augier R Diagana M De Reggi M Gharib B 《Cellular and molecular life sciences : CMLS》2001,58(9):1350-1357
We investigated the nitric oxide (NO) synthase and arginase pathways in resident peritoneal macrophages of mice infected
with the tropical parasite Schistosoma mansoni. The two enzymes may have opposite effects, insofar as NO may be involved in the killing of the parasite whereas arginase
may stimulate parasite growth via polyamine synthesis. We determined the effects of the infection on the expression and activity
of the two enzymes in macrophages, before and after cytokine activation. Cells from infected mice expressed the hepatic type
I arginase, whereas in control cells, the enzyme was expressed only after cytokine activation, as were NO synthase II and
type II arginase in both groups of cells. Moreover, we found that in infected mice, arginase expression in macrophages was
associated with a ten fold increase in the concentration of circulating ornithine-derived polyamines. This may be of pathological
importance, since parasitic helminths are though to be dependent on their hosts for the uptake and interconversion of polyamines.
Received 13 March 2001; received after revision 4 May 2001; accepted 7 June 2001 相似文献
19.
Role of bombesin-related peptides in the mediation or integration of the stress response 总被引:3,自引:0,他引:3
In addition to the relatively well established role of corticotropin-releasing hormone (CRH) and arginine-vasopressin (AVP)
in the mediation of the stress response, there is reason to believe that bombesin-like peptides (BN-LPs) may also contribute
to the mediation or integration of these responses and thus might be considered as putative 'stress peptides'. This review
provides evidence supporting this contention by showing that (i) BN-LPs are present at brain sites known to be activated by
stressors, (ii) stressor exposure alters utilization of BN-related peptides, (iii) exogenous BN administration mimics the
endocrine, autonomic and/or behavioral effects elicited by stressors, and (iv) antagonism of BN action attenuates the behavioral
and/or neurochemical effects of stressors or of exogenously administered peptide. The evidence presented also suggests that
BN-LPs mediate their stress-relevant effects through activation of CRH and/or AVP neurons. Several hypothetical mechanisms
for such peptidergic interactions are discussed as to the implications of considering BN-LPs as 'stress peptides'.
Received 16 July 2001; received after revision 27 August 2001; accepted 28 August 2001 相似文献
20.
Lisowska E 《Cellular and molecular life sciences : CMLS》2002,59(3):445-455
Glycosylation of proteins is a common event and contributes to protein antigenic properties. Most data have been obtained
from model studies on glycoprotens with well-defined structure or synthetic glycopeptides and their respective monoclonal
antibodies. Antibodies raised against glycoprotein antigens may be specific for their carbohydrate units which are recognized
irrespective of the protein carrier (carbohydrate epitopes), or in the context of the adjacent amino acid residues (glycopeptidic
epitopes). Conformation or proper exposure of peptidic epitopes of glycoproteins is also frequently modulated by glycosylation
due to intramolecular carbohydrate-protein interactions. The effects of glycosylation are broad: glycosylation may 'inactivate'
the peptidic epitope or may be required for its reactivity with the antibody, depending on the structure of the antigenic
site and antibody fine specificity. Evidence is increasing that similar effects of glycosylation pertain to T cell-dependent
cellular immune responses. Glycosylated peptides can be bound and presented by MHC class I or II molecules and elicit glycopeptide-specific
T cell clones.
Received 5 July 2001; received after revision 9 October 2001; accepted 11 October 2001 相似文献