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1.
N Faucon-Biguet D Samolyk P Tournier 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1979,288(5):563-565
Simian adenovirus 7, either complete virus or its capsid subunits, agglutinates Rat (Sprague-Dowley) red blood cells in the presence of heterotypical antiserum. Haemagglutination takes place at 4 degrees C and room temperature. The antigen could not be eluted and its haemagglutinin properties are heat-stable. The reaction is specific. It is inhibited by homologous antiserum only. This property and its characteristics permit a camparison of this strongly oncogenic adenovirus to the human adenovirus of subgroup III of Rosen. 相似文献
2.
The mitochondrial PHB complex: roles in mitochondrial respiratory complex assembly, ageing and degenerative disease 总被引:16,自引:0,他引:16
Nijtmans LG Artal SM Grivell LA Coates PJ 《Cellular and molecular life sciences : CMLS》2002,59(1):143-155
Although originally identified as putative negative regulators of the cell cycle, recent studies have demonstrated that the
PHB proteins act as a chaperone in the assembly of subunits of mitochondrial respiratory chain complexes. The two PHB proteins,
Phb1p and Phb2p, are located in the mitochondrial inner membrane where they form a large complex that represents a novel type
of membrane-bound chaperone. On the basis of its native molecular weight, the PHB-complex should contain 12-14 copies of both
Phb1p and Phb2p. The PHB complex binds directly to newly synthesised mitochondrial translation products and stabilises them
against degradation by membrane-bound metalloproteases belonging to the family of mitochondrial triple-A proteins. Sequence
homology assigns Phb1p and Phb2p to a family of proteins which also contains stomatins, HflKC, flotillins and plant defence
proteins. However, to date only the bacterial HflKC proteins have been shown to possess a direct functional homology with
the PHB complex. Previously assigned actions of the PHB proteins, including roles in tumour suppression, cell cycle regulation,
immunoglobulin M receptor binding and apoptosis seem unlikely in view of any hard evidence in their support. Nevertheless,
because the proteins are probably indirectly involved in ageing and cancer, we assess their possible role in these processes.
Finally, we suggest that the original name for these proteins, the prohibitins, should be amended to reflect their roles as
proteins that hold badly formed subunits, thereby keeping the nomenclature already in use but altering its meaning to reflect
their true function more accurately.
Received 21 May 2001; received after revision 2 July 2001; accepted 24 July 2001 相似文献
3.
4.
P. Cappuccinelli Irene Cagliani G. Cavallo 《Cellular and molecular life sciences : CMLS》1975,31(10):1157-1159
Summary Treatment ofTrichomonas vaginalis with EDTA removes their ability to adhere to glass surfaces and changes their affinity to Concanavalin A (ConA) by a different
distribution of their surface structures. Filtrates of the EDTA-treatedTrichomonas passed through affinity chromatography columns (ConA bound to Sepharose 4B0 separate into 2 fractions, one fraction was bound
to the ConA-Sepharose beads, the other was not. The Con A-bound fraction appears to be a glycoprotein which restores in a
specific way the ability of the EDTA-treated protozoa to adhere to glass.
We want to thank Dr.P. M. Comoglio for the donation of the FITC-labelled immunoglobulin fraction of anti-ConA rabbit antiserum. This work was supported by a
grant from the Italian National Research Council (C.N.R.) 相似文献
5.
Rabbit anti-rat brain synaptic vesicle serum reacted with thymocytes and B lymphocytes in cytotoxicity and immunofluorescence assays. Quantitative absorption analysis revealed that this antiserum contained antibodies specific for antigenic determinants on the surface membrane of a subpopulation of rat bone marrow B lymphocytes. 相似文献
6.
A V Sanin 《Experientia》1987,43(4):432-433
Utilizing specific rabbit antiserum against M. arthritidis together with complement, a portion of the marrow 7-day CFUs population of CBA mice infected with live mycoplasma organisms 1 day previously was shown to be inactivated. These cells might therefore be considered as candidate target cells for M. arthritidis. 11-day CFUs were unaffected by similar treatment. 相似文献
7.
Identification of tyrosine-phosphorylated proteins of the mitochondrial oxidative phosphorylation machinery 总被引:1,自引:1,他引:0
Augereau O Claverol S Boudes N Basurko MJ Bonneu M Rossignol R Mazat JP Letellier T Dachary-Prigent J 《Cellular and molecular life sciences : CMLS》2005,62(13):1478-1488
The role of some serine/threonine kinases in the regulation of mitochondrial physiology is now well established, but little is known about mitochondrial tyrosine kinases. We showed that tyrosine phosphorylation of rat brain mitochondrial proteins was increased by in vitro addition of ATP and H2O2, and also during in situ ATP production at state 3, and maximal reactive oxygen species production. The Src kinase inhibitor PP2 decreased tyrosine phosphorylation and respiratory rates at state 3. We found that the 39-kDa subunit of complex I was tyrosine phosphorylated, and we identified putative tyrosine-phosphorylated subunits for the other complexes. We also have strong evidence that the FoF1-ATP synthase α chain is probably tyrosine-phosphorylated, but demonstrated that the β chain is not. The tyrosine phosphatase PTP 1B was found in brain but not in muscle, heart or liver mitochondria. Our results suggest that tyrosine kinases and phosphatases are involved in the regulation of oxidative phosphorylation.Received 7 January 2005; received after revision 19 April 2005; accepted 22 April 2005 相似文献
8.
J. -L. Carpentier P. Gorden A. Robert L. Orci 《Cellular and molecular life sciences : CMLS》1986,42(7):734-744
Conclusion The insulin receptor is an integral protein of the plasma membrane of the cell. It is composed of two subunits: an subunit, which binds the hormone, and a subunit which is a tyrosine specific protein kinase capable of undergoing autophosphorylation. These independent subunits are synthesized by way of a higher molecular weight single chain precursor and thus are the product of a single gene29, 49, 85 localized to chromosome 1929, 91. Assuming that the insulin receptor is synthesized in the same fashion as other integral membrane glycoproteins, then the nucleus, the rough endoplasmic reticulum, and the Golgi apparatus are involved in its biosynthesis. Further, there must be some form of transport of the mature receptor subunits to the plasma membrane where they are inserted.By contrast, the endocytotic route involves coated pits, coated vesicles, large clear vesicles or endosomes, multivesicular bodies and other lysosomal forms. In addition, it is possible that some other as yet unidentified organelle is involved in recycling (fig. 8). At the present time, with respect to the insulin receptor, the biosynthetic pathway and the endocytotic pathway appear to be separate. Further, it does not appear that either pathway, i. e. synthesis or endocytosis, exerts a regulatory function over the other. 相似文献
9.
B. D. Janković J. Horvat Kosana Mitrović 《Cellular and molecular life sciences : CMLS》1979,35(10):1393-1395
Summary Rabbit anti-rat brain synaptic vesicle serum reacted with thymocytes and B lymphocytes in cytotoxicity and immunofluorescence assays. Quantitative absorption analysis revealed that this antiserum contained antibodies specific for antigenic determinants on the surface membrane of a subpopulation of rat bone marrow B lymphocytes.This work was supported by the Republic of Serbia Research Fund, Belgrade. 相似文献
10.
R. Benz 《Cellular and molecular life sciences : CMLS》1990,46(2):131-137
Summary The matrix space of mitochondria is surrounded by two membranes. The mitochondrial inner membrane contains the respiration chain and a large number of highly specific carriers for the mostly anionic substrates of mitochondrial metabolism. In contrast to this the permeability properties of the mitochondrial outer membrane are by far less specific. It acts as a molecular sieve for hydrophilic molecules with a defined exclusion limit around 3000 Da. Responsible for the extremely high permeability of the mitochondrial outer membrane is the presence of a pore-forming protein termed mitochondrial porin. Mitochondrial porins have been isolated from a variety of eukaryotic cells. They are basic proteins with molecular masses between 30 and 35 kDa. Reconstitution experiments define their function as pore-forming components with a single-channel conductance of about 0.40 nS (nano Siemens) in 0.1 M KCl at low voltages. In the open state mitochondrial porin behaves as a general diffusion pore with an effective diameter of 1.7 nm. Eukaryotic porins are slightly anion-selective in the open state but become cation-selective after voltage-dependent closure. 相似文献
11.
The role of glycosylation in ionotropic glutamate receptor ligand binding, function, and trafficking
Members of the ionotropic glutamate receptor (iGluR) family have between 4 and 12 consensus asparagine (N)-linked glycosylation sites. They are localized on the extracellular N-termini, and the loop between the penultimate and last transmembrane domains. These regions also contain the essential elements for formation of the ligand binding site. N-linked glycosylation does not appear to be essential for formation of the ligand binding site per se, but there are demonstrated interactions between glycosylation state and ligand binding affinity, receptor physiology, susceptibility to allosteric modulation and, in some cases, trafficking. There is no indication of a general role for N-linked glycosylation in iGluRs; instead the effects of glycosylation vary among glutamate receptor subtypes and splice variants, with specific effects on structure or function with different subunits. 相似文献
12.
A. V. Sanin 《Cellular and molecular life sciences : CMLS》1987,43(4):432-433
Summary Utilizing specific rabbit antiserum againstM. arthritidis together with complement, a portion of the marrow 7-day CFUs population of CBA mice infected with live mycoplasma organisms 1 day previously was shown to be inactivated. These cells might therefore be considered as candidate target cells forM. arthritidis. 11-day CFUs were unaffected by similar treatment. 相似文献
13.
R Benz 《Experientia》1990,46(2):131-137
The matrix space of mitochondria is surrounded by two membranes. The mitochondrial inner membrane contains the respiration chain and a large number of highly specific carriers for the mostly anionic substrates of mitochondrial metabolism. In contrast to this the permeability properties of the mitochondrial outer membrane are by far less specific. It acts as a molecular sieve for hydrophilic molecules with a defined exclusion limit around 3000 Da. Responsible for the extremely high permeability of the mitochondrial outer membrane is the presence of a pore-forming protein termed mitochondrial porin. Mitochondrial porins have been isolated from a variety of eukaryotic cells. They are basic proteins with molecular masses between 30 and 35 kDa. Reconstitution experiments define their function as pore-forming components with a single-channel conductance of about 0.40 nS (nano Siemens) in 0.1 M KCl at low voltages. In the open state mitochondrial porin behaves as a general diffusion pore with an effective diameter of 1.7 nm. Eukaryotic porins are slightly anion-selective in the open state but become cation-selective after voltage-dependent closure. 相似文献
14.
Human mitochondrial tRNAs in health and disease 总被引:6,自引:0,他引:6
Florentz C Sohm B Tryoen-Tóth P Pütz J Sissler M 《Cellular and molecular life sciences : CMLS》2003,60(7):1356-1375
The human mitochondrial genome encodes 13 proteins, all subunits of the respiratory chain
complexes and thus involved in energy metabolism. These genes are translated by 22 transfer RNAs
(tRNAs), also encoded by the mitochondrial genome, which form the minimal set required for reading
all codons. Human mitochondrial tRNAs gained interest with the rapid discovery of correlations
between point mutations in their genes and various neuromuscular and neurodegenerative disorders.
In this review, emerging fundamental knowledge on the structure/function relationships of these
particular tRNAs and an overview of the large variety of mechanisms within translation, affected by
mutations, are summarized. Also, initial results on wide-ranging molecular consequences of mutations
outside the frame of mitochondrial translation are highlighted. While knowledge of mitochondrial
tRNAs in both health and disease increases, deciphering the intricate network of events leading
different genotypes to the variety of phenotypes requires further investigation using adapted
model systems.Received 3 December 2002; received after revision 14 January 2003; accepted 27 January 2003 相似文献
15.
Summary One major antigen, present in female cuticle, female blood and eggs, is revealed by the antiserum against soluble cuticular proteins of adults locusts, and by all the antisera against vitellin or vitellogenin. It is not revealed by the specific antiserum against diglyceride-binding lipoprotein. The presence of this major antigen in the cuticle depends on the presence of vitellogenin in the blood. 相似文献
16.
The biogenesis and function of eukaryotic porins. 总被引:2,自引:0,他引:2
M Dihanich 《Experientia》1990,46(2):146-153
Like most other mitochondrial proteins porin is synthesized in the cytosol and imported posttranslationally into the outer mitochondrial membrane. This transport follows the general rules for mitochondrial protein import with a few aberrations: a) porin contains an uncleaved NH2-terminal signal sequence, b) also its carboxyterminus might be involved in the import process, and c) this transport does not seem to require a membrane potential delta psi, although it is ATP-dependent. Most likely the actual import step occurs at contact sites between the outer and the inner mitochondrial membrane and involves at least one receptor protein. Although porin is known to be the major gate through the outer mitochondrial membrane, its absence only causes transient respiratory problems in yeast cells. This could mean a) that there is a bypass for some mitochondrial functions in the cytosol and/or b) that there are alternative channel proteins in the outer membrane. The first idea is supported by the overexpression of cytosolic virus-like particles in yeast cells lacking porin and the second by the occurrence of residual pore activity in mitochondrial outer membrane purified from porinless mutant cells. 相似文献
17.
The metabotropic GABA receptor: molecular insights and their functional consequences 总被引:2,自引:0,他引:2
Recent years have seen rapid and significant advances in our understanding of the G-protein-coupled gamma-amino butyric acid, B-type (GABA(B)) receptor, which could be a therapeutic target in conditions as diverse as epilepsy and hypertension. This progress originated with the ground-breaking work of Bernhard Bettler's team at Novartis who cloned the DNA encoding a GABA(B) receptor in 1997. Currently, the receptor is thought to be an unusual, possibly unique, example of a heterodimer composed of homologous, seven-transmembrane-domain (7TMD) subunits (named GABA(B) R1 and GABA(B) R2), neither of which is fully functional when expressed alone. The large N-terminal domain of the GABA(B) R1 subunit projects extracellularly and contains a ligand binding site. The similarity of the amino acid sequence of this region to some bacterial periplasmic amino acid-binding proteins of known structure has enabled structural and functional modelling of the N-terminal domain, and the identification of residues whose substitution modulates agonist/antagonist binding affinities. The intracellular C-terminal domains of the R1 and R2 subunits appear to constitute an important means of contact between the two subunits. Alternative splice variants, a common and functionally important feature of 7TMD proteins, have been demonstrated for the R1 subunit. Notably GABA(B) R1a differs from GABA(B) R1b by the possession of an N-terminal extension containing two complement protein modules (also called SCRs, or sushi domains) of unknown function. The levels at which each of the respective variants is expressed are not equal to one another, with variations occurring over the course of development and throughout the central nervous system. It is not yet clear, however, whether one variant is predominantly presynaptically located and the other postsynaptically located. The existence of as yet unidentified splice variants, additional receptor subtypes and alternative quaternary composition has not been ruled out as a source of receptor heterogeneity. 相似文献
18.
Rai A Nöthe H Tzvetkov N Korenbaum E Manstein DJ 《Cellular and molecular life sciences : CMLS》2011,68(16):2751-2767
Dictyostelium discoideum cells produce five dynamin family proteins. Here, we show that dynamin B is the only member of this group of proteins that
is initially produced as a preprotein and requires processing by mitochondrial proteases for formation of the mature protein.
Our results show that dynamin B-depletion affects many aspects of cell motility, cell-cell and cell-surface adhesion, resistance
to osmotic shock, and fatty acid metabolism. The mature form of dynamin B mediates a wide range and unique combination of
functions. Dynamin B affects events at the plasma membrane, peroxisomes, the contractile vacuole system, components of the
actin-based cytoskeleton, and cell adhesion sites. The modulating effect of dynamin B on the activity of the contractile vacuole
system is unique for the Dictyostelium system. Other functions displayed by dynamin B are commonly associated with either classical dynamins or dynamin-related
proteins. 相似文献
19.
F B Ubatuba 《Experientia》1979,35(12):1637-1638
Horse platelets release an unidentified smooth muscle contracting substance after lysis by antiserum and complement. Since the active factor (thrombocytolysin) does not produce tachyphylactic response of the guinea-pig ileum it seems that it is not related to anaphylatoxins. 相似文献
20.
Summary Prolactin levels in mouse milk increased from the day of parturition to give a concentration of 230 ng/ml on days 2 and 3 of lactation. Thereafter, levels dropped to 140 ng/ml by day 6 and were maintained at this concentration until weaning.Acknowledgments. Mouse PRL and its antiserum was the generous gift of Y.N. Sinha (Scripps Clinic and Research Foundation, La Jolla, California). J.M.B. was in receipt of a Liverpool University Studentship. 相似文献