Vol. 9 No. 2 June 2004
| Volume 9 (2004) pp 195-220 | |
| Title | CAVEOLINS: STRUCTURE AND FUNCTION IN SIGNAL TRANSDUCTION |
| Authors | Wanda M. Krajewska* and Izabela Masłowska |
| Abstract | The caveolin family proteins are typically associated with microdomains that are found in the plasma membrane of numerous cells. These microdomains are referred to as/called caveolae. Caveolins are small proteins (18-24 kDa) that have a hairpin loop conformation with both the N and C termini exposed to the cytoplasm. Apart from having a structural function within caveolae, these proteins have the capacity to bind cholesterol as well as a variety of proteins, such as receptors, Src-like kinases, G-proteins, H-Ras, MEK/ERK kinases and nitric oxide synthases, which are involved in signal transduction processes. Considerable data allow the assumption to be made that the majority of the interactions with signaling molecules hold them in an inactive or repressed state. The activity of caveolins seems to be dependent on its specific post-translation modifications. It is suggested that caveolins fulfill a role in the modulation of cellular signaling cascades. |
| Address and Contact Information | University of Łódź, Department of Cytobiochemistry, Banacha 12/16,
90-237 Łódź, Poland * Corresponding author, E-mail: wmkraj@biol.uni.lodz.pl |
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| Volume 9 (2004) pp 221-238 | |
| Title | CHARACTERISTICS AND A COMPARISON OF THREE CLASSES OF MICROSATELLITE-BASED MARKERS AND THEIR APPLICATION IN PLANTS |
| Authors | Monika Rakoczy-Trojanowska* and Hanna Bolibok |
| Abstract | The effect of triethyllead (TriEL) on the morphology and motile activity of Walker 256 carcinosarcoma cells was investigated. It was found that both 2 and 5 mM TriEL affected the cellular motility in a dose- and timedependent manner. Initially, 2 mM TriEL caused the formation of blebs instead of lamellipodia at the front of some cells and stimulated the migration of Walker cells, but after 2 hours of 2 mM TriEL treatment, a reduction of cellular motility was observed. In the presence of 5 mM TriEL, Walker 256 carcinosarcoma cells rounded up, and their rate of movement was reduced. Moreover, the treatment of Walker carcinosarcoma cells with TriEL caused the disruption of microtubules and affected the F-actin distribution at both concentrations. At a concentration of 2 mM TriEL, the actin staining intensity was greatest in the tail of front-tail polarised blebbing cells and the actin layer was very thin at the leading edge. The control cells showed linear cortical F-actin distribution and somewhat less intense cytoplasmic staining at the same TriEL concentration. Cells treated with 5 mM TriEL showed an under-membrane pattern of actin distribution. |
| Address and Contact Information | Department of Plant Genetics, Breeding and Biotechnology, Warsaw
Agricultural University, Nowoursynowska 166, 02-787 Warszawa, Poland * Corresponding author, e-mail: rakoczy@alpha.sggw.waw.pl |
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| Volume 9 (2004) pp 239-251 | |
| Title | A COMPARISON OF GROUP II INTRONS OF PLASTID tRNALys UUU GENES ENCODING MATURASE PROTEIN |
| Authors | Kamila Jankowiak, Joanna Lesicka, Andrzej Pacak, Agnieszka Rybarczyk and Zofia Szweykowska-Kulińska* |
| Abstract | All higher plant plastid genomes have six classes of tRNA genes containing introns. One of those is the tRNALys UUU gene, which encodes maturase protein. In the case of liverwort species from the genus Porella and mosses from the genus Plagiomnium, the maturase coding gene (matK) represents a truncated form of other plant matK genes: several subdomains of the reverse transcriptase-like domain and so-called domain X are not present in these ORFs. These ORFs probably represent pseudogenes of the matK gene. The analysis of codon usage within the matK gene revealed the presence of strong A/T pressure. The use of codons with the third letter being U or A varies from 71-93%. The comparison of maturase amino acid sequences at the family level shows a high identity between species. However, when liverwort and angiosperm maturase sequences are compared, the percentage of identity drops dramatically. The calculated values of the number of nucleotide substitutions vary considerably, even when liverwort species are compared pairwise. The phenetic tree of relationships between plant species on the basis of tRNALys UUU intron sequences concur with the generally accepted plant phylogeny. |
| Address and Contact Information | Department of Gene Expression, Institute of Molecular Biology and
Biotechnology, Adam Mickiewicz University, Międzychodzka 5,
60-371 Poznał, Poland * Corresponding author; e-mail: zofszwey@main.amu.edu.pl, fax: (+4861)8292730. |
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| Volume 9 (2004) pp 253-259 | |
| Title | PREPARATION OF ENDOTOXIN-FREE BACTERIOPHAGES |
| Authors | Janusz Boratyński1*, Danuta Syper2, Beata Weber-Dąbrowska2, Marzanna Łusiak-Szelachowska2, Gryzelda Poźniak3 and Andrzej Górski2,4 |
| Abstract | Bacteriophages (phages) are bacterial viruses that interact with bacterial walls and invade bacterial cells. Moreover, they disturb bacterial metabolism and lead to bacteria lysis. In the case of Gram-negative bacteria crude phage cultures, apart from the phages themselves, the bacterial debris, bacterial proteins and nucleic acids contain endotoxins. These endotoxins (lipopolysaccharides) posses a high degree of toxicity in vitro and in vivo, and their removal is essential for safety in antibacterial bacteriophage therapy. An effective, scaleable purification of bacteriophages from endotoxins was accomplished by sequential ultrafiltration through polysulfone membrane (30 nm) followed by chromatography on sepharose 4B and Matrex Cellulofine Sulfate. The phage fraction after gel filtration chromatography routinely contained endotoxins in the 150-2500 EU/mL range. The procedure yielded bacteriophages contaminated with as little as 0.4-7 EU/ml (Limulus assay). This value lies within the permitted level for intravenous applications (5 EU/kg/h by European Pharmacopoeia, 1997). |
| Address and Contact Information | 1Laboratory of Biomedical Chemistry, Department of Experimental Oncology
and 2Laboratory of Bacteriophages, Institute of Immunology and Experimental
Therapy, Polish Academy of Sciences, Rudolfa Weigla 12, 53-114 Wrocław,
Poland, 3Institute of Organic and Polymer Technology, Wrocław University of Technology, 4Transplantation Institute, Medical University of Warsaw, Nowogrodzka 59, 02-006 Warszawa, Poland * Corresponding author; e-mail: borat@iitd.pan.wroc.pl |
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| Volume 9 (2004) pp 261-270 | |
| Title | DAMAGE TO ERYTHROCYTES CAUSED BY 2,3,7,8-TETRACHLORODIBENZO- P-DIOXIN (in vitro) |
| Authors | Bożena Bukowska |
| Abstract | The effects of the exposure of human erythrocytes to different concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin were studied. Particular attention was paid to lipid peroxidation, haemoglobin oxidation, and changes in the activity of catalase and glutathione peroxidase. Human erythrocytes at a 5% haematocrit were incubated with 2,3,7,8-TCDD at concentrations of 0.2 ppm to 1.6 ppm (ng-mg/ml erythrocytes) for 1 hour. The results obtained show that 2,3,7,8-TCDD induces the generation of lipid peroxides and the oxidation of Hb, and decreases the activity of catalase and glutathione peroxidase. This supports the thesis that TCDD causes oxidative stress in erythrocytes. |
| Address and Contact Information | Department of the Biophysics of Environmental Pollution, University of Łódź,
Banacha 12/16, 90-237 Łódź, Poland |
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| Volume 9 (2004) pp 271-286 | |
| Title | a- KETOGLUTARATE DEHYDROGENASE AND LIPOIC ACID SYNTHASE ARE IMPORTANT FOR THE FUNCTIONING OF PEROXISOMES OF Saccharomyces cerevisiae |
| Authors | Iwona Smaczyłska-De Rooij*, Andrzej Migdalski and Joanna Rytka** |
| Abstract | A method was devised to search for yeast mutants impaired in peroxisome functioning, indicating cross-talk between metabolic pathways. Two mutants were isolated; they are impaired in oleate utilisation and carry mutations in the KGD1 and LIP5 genes encoding the E1 component of the mitochondrial a-ketoglutarate dehydrogenase complex and lipoic acid synthase, respectively. The results presented indicate that the Kgd1 and Lip5 proteins are important for the expression of genes encoding peroxisomal matrix proteins, although they are not necessary for the biogenesis of this cellular compartment. |
| Address and Contact Information | Institute of Biochemistry and Biophysics, Polish Academy of Sciences,
Pawiłskiego 5A, 02-106 Warsaw, Poland * Current address: Department of Biochemistry, Academic Medical Center, University of Amsterdam, Meibergdreef 15, The Netherlands. ** Corresponding author, e-mail: rytka@psd.ibb.waw.pl |
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| Volume 9 (2004) pp 287-300 | |
| Title | Agrobacterium-MEDIATED TRANSFORMATION OF BANGLADESHI INDICA RICES |
| Authors | Mohammad Al-Forkan1, J. Brian Power1, Paul Anthony1, Kenneth C. Lowe2 and Michael R. Davey1* |
| Abstract | Morphologically normal, fertile transgenic plants were obtained by co-culturing embryogenic calli of the Bangladeshi Indica rice cultivars BR26 and Binni with Agrobacterium tumefaciens strain LBA4404 carrying the super binary vector pTOK233. Acetosyringone (100 µM) in the medium during coculture (25-28oC) and selection on hygromycin B (50 mg l-1) were essential for efficient transformation. Stable integration and expression of ß-glucuronidase, neomycin phosphotransferase and hygromycin phosphotransferase genes in regenerated plants were confirmed by histochemical and fluorometric assays, ELISA and Southern analysis. Two to 3 copies of T-DNA were integrated into regenerated plants; transgene expression did not correlate with gene copy number. Mendelian segregation of transgenes occurred in T1 seed progeny. |
| Address and Contact Information | 1Plant Sciences Division, School of Biosciences, University of Nottingham,
Sutton Bonington Campus, Loughborough LE12 5RD, UK, 2School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK * Corresponding author, E-mail: mike.davey@nottingham.ac.uk |
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| Volume 9 (2004) pp 301-304 | |
| Title | THE PROTECTIVE EFFECTS OF LIDOCAINE ON HUMAN ERYTHROCYTES STORED FOR SEVEN DAYS AT 04oC |
| Authors | Francois Lenfant1, Jean-Jacques Lahet2, Bernard Chaillot2 and Marc Freysz1 |
| Abstract | Erythrocyte storage may result in cell damage due to an alteration of membrane integrity, which results in potassium efflux and hemolysis. Lidocaine has been shown to protect erythrocytes from oxidative stress by a possible membrane effect. We conducted this study to examine the effects of lidocaine on human erythrocyte storage. Erythrocytes were kept for seven days at 04oC in the absence or in presence of plasma, and of lidocaine at 36.9 and 221.6 mM. Cell damage was assessed by measuring potassium efflux in the supernatant after seven days, and studying potassium efflux and hemolysis induced by oxidative stress. As expected, erythrocyte storage in the presence of plasma was less deleterious. Lidocaine decreased potassium efflux after 7 days' storage. Resistance toward oxidative stress was greater when the erythrocytes had been kept in the presence of plasma. Considering that lidocaine is widely used in various clinical situations, this data may be of clinical relevance. |
| Address and Contact Information | 1Département d’Anésthesie Réanimation, CHU de Dijon, Hôpital Général, 3 rue
du Faubourg Raines, 21033 Dijon, France, 2Laboratoire de Chimie Bio- Inorganique, Faculté de Pharmacie de Dijon, 7 boulevard Jeanne d’Arc, 21079 Dijon, France |
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| Volume 9 (2004) pp 305-328 | |
| Title | GALECTIN-3 AS A MULTIFUNCTIONAL PROTEIN |
| Authors | Anna Krześlak And Anna Lipińska* |
| Abstract | Galectin-3 is a 31 kDa member of a growing family of b-galactosidebinding animal lectins. This protein is expressed in a variety of tissues and cell types and is mainly found in the cytoplasm, although, depending on cell type and proliferative state, a significant amount of this lectin can also be detected in the nucleus, on the cell surface or in the extracellular environment. Galectin-3 is secreted from cells by a novel and incompletely understood mechanism that is independent of the classical secretory pathway through the endoplasmic reticulum/Golgi network. Galectin-3 exhibits pleiotropic biological function, playing a key role in many physiological and pathological processes. |
| Address and Contact Information | University of Łódź, Department of Cytobiochemistry, Banacha 12/16,
90-237 Łódź, Poland * Corresponding author, e-mail: annal@biol.uni.lodz.pl |
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| Volume 9 (2004) pp 329-336 | |
| Title | SELENIUM AS A SULPHYDRYLIC GROUP INDUCTOR IN PLANTS |
| Authors | Barbara Hawrylak and Maria Szymałska* |
| Abstract | We investigated the effect of selenium form and dose on the total glutathione and non-protein -SH group contents in the edible spinach (Spinacia oleracea L.) and ground tomato (Lycopersicon esculentum Mill.) plants. Our experiments were carried out in a hydroponic culture. Selenium was added to the culture medium in its selenite (Na2SeO3 x 5H2O) and selenate (Na2SeO4) forms. Regardless of the selenium form, we observed an increase in the non-protein thiol content. The non-protein -SH group content depended on the form and dose of selenium as well as on the organ and plant species. Regardless of the selenium form, a higher content of non-protein -SH groups were found in the spinach biomass than in the tomato biomass. Selenite contributed to a larger accumulation of non-protein -SH groups in the roots, whereas selenate contributed to their accumulation in the shoots. |
| Address and Contact Information | Agricultural University, Department of Plant Physiology, Akademicka 15,
20-950 Lublin, Poland * Corresponding author; e-mail: metal@agros.ar.lublin.pl |
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| Volume 9 (2004) pp 337-351 | |
| Title | THE ROLE OF TARGET MEMBRANE SIALIC ACID RESIDUES IN THE FUSION ACTIVITY OF THE INFLUENZA VIRUS: THE EFFECT OF TWO TYPES OF GANGLIOSIDE ON THE KINETICS OF MEMBRANE MERGING |
| Authors | Joao Ramalho-Santos1,3*and Maria C. Pedroso De Lima1,2 |
| Abstract | The influenza virus enters target cells via the action of hemagglutinin proteins (HA) inserted into the viral envelope. HA promotes membrane fusion between the viral envelope and endosomal membrane at low pH, following viral binding to sialic acid-containing receptors on target cells, and internalization by endocytosis. The effect of target membrane sialic acid residues on the fusion activity of the influenza virus towards model membranes was evaluated by both reduction, (i.e. treating somatic cells with neuraminidase- (NA-) prior to virus-cell interactions), and by supplementing liposomes with the gangliosides GD1a and GT1b. The harshness of the neuraminidase pretreatment of target cells required to affect virus-induced membrane merging was found to greatly depend on the assay conditions, i.e. whether a virus-cell prebinding step at neutral pH was included prior to acidification. Minor concentrations of neuraminidase were found to greatly reduce virus fusion, but only in the absence of a prebinding step; they had no effect if this step was included. Although membrane merging was greatly reduced following cell neuraminidase pretreatment, virus-cell association at low pH was not disturbed proportionately. This probably reflects unspecific virus-cell binding under these conditions, probably of inactivated or aggregated virus particles, which does not translate into membrane merging. This seems to suggest both that target membrane sialic acid can protect the virus from losing its activity before triggering membrane merging, and that the importance of this interaction is not merely to ensure virus-target proximity. With liposomes, we found that both types of ganglioside supported efficient fusion, with GD1a promoting a slightly faster initial rate. However, in this case, virus-target proximity closely mirrored fusion activity, thus pointing to differential specificity between targets routinely used to assay influenza virus fusion activity. |
| Address and Contact Information | 1Center for Neuroscience and Cell Biology, University of Coimbra, Portugal, 2Department of Biochemistry, University of Coimbra, Portugal, 3Department of Zoology, University of Coimbra, 3004-517 Coimbra, Portugal * Corresponding author; phone: + 351 (239) 834729, fax: + 351 (239) 826798; e-mail: jramalho@ci.uc.pt |
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| Volume 9 (2004) pp 353-361 | |
| Title | A COMPARISON OF CALLUS INDUCTION AND PLANT REGENERATION FROM DIFFERENT EMBRYO EXPLANTS OF TRITICALE (x Triticosecale Wittmack) |
| Authors | Melahat A. Birsin and Murat Özgen* |
| Abstract | Immature, mature and endosperm-supported mature embryos of six triticale cultivars (BDMT-98-8S, Melez-2001, Mikham-2002, Presto, Tacettin Bey and Tatlicak-97) were cultured in vitro to compare the levels of callus induction and plant regeneration. Immature embryos, 15-18 days after anthesis, were aseptically excised and placed with the scutellum upwards on a callus culture medium consisting of Murashige and Skoog (MS) mineral salts supplemented with 2 mg l-1 2,4-dichlorophenoxyacetic acid (2,4-D). Mature embryos were aseptically excised from the imbibed seeds and placed scutellum up on MS medium supplement with 2 mg l-1 2,4-D. Endosperm-supported mature embryos were moved slightly in the imbibed mature seeds. The seeds with moved embryos were placed furrow downwards in dishes containing 8 mg l-1 2,4-D for callus induction. The developed calli and regenerated plants were maintained on hormone-free MS medium. Variability among the genotypes was observed for all the types of embryo culture. Immature embryos from “Presto” and endosperm-supported mature embryos from “Mikham 2002” had excellent regeneration capacities (92.0% and 97.3%, respectively) and the highest number of plants regenerated growing in soil (9 and 13, respectively). A comparison of the responses of the three explants used indicated that the endosperm-supported mature embryo was the most useful explant for plant regeneration in triticale. |
| Address and Contact Information | Department of Field Crops, Faculty of Agriculture, University of Ankara,
06110 Diskapi, Ankara, Turkey * Corresponding author, e-mail: mozgen@tr.net |
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| Volume 9 (2004) pp 363-373 | |
| Title | NUCLEUS PULPOSUS REPAIR WITH CULTURED AUTOLOGOUS ELASTIC CARTILAGE DERIVED CHONDROCYTES |
| Authors | Matevž Gorenšek1, Čedomir Joksimović2, Nevenka Kregar-Velikonja1, Miro Gorenšek3, Miomir Knežević1, Matjaž Jeras4, Vinko Pavlovčič3 and Andrej Cör2 |
| Abstract | Low back pain is one of the most common medical conditions in the Western world. Disc degeneration, an inevitable process of ageing, is one of the major causes of low back pain. Autologous chondrocyte transplantation (ACT) is an increasingly popular method of addressing pathological disorders of cartilage. The purpose of our study was to determine whether autologous chondrocytes from elastic cartilage could survive and synthesise a cartilage specific matrix in the intervertebral disc of rabbits. Sixteen lumbar intervertebral discs (IVD) of New Zealand White rabbits were analysed. In 6 IVD, the nucleus pulposus was evacuated and replaced with tissue engineered autologous chondrocytes from auricular cartilage. In the second group, only the nucleus pulposus was evacuated from 6 IVD, with no chondrocytes implantation. Four non-operated IVD were used as a control. Six months after the operation, the animals were euthanized and the IVD were analysed histologically. Autologous cartilage implants were well tolerated by the host for up to six months in vivo. There was only hyaline-like cartilage in the place of the nucleus pulposus. We could not detect any elastic fibres in the new cartilage matrix. In IVD from which only the nucleus pulposus was evacuated and no chondrocytes were implanted, just fibrous tissue was found instead of nucleus pulposus. The overall histological analysis of new cartilage produced after implantation in our study confirmed the hypothesis that ACT from auricular cartilage can be implanted into the IVD instead of the nucleus pulposus and that a significant percentage of implanted chondrocytes survive and produce hyaline-like cartilage. |
| Address and Contact Information | 1Educell Ljubljana, Slovenia, 2Institute for Histology and Embryology, Medical
Faculty, Korytkova 2, 1000 Ljubljana, Slovenia, 3Departement of Orthopaedic Surgery, University Clinical Centre, Ljubljana, Slovenia, 4Tissue Typing Centre, Blood Transfusion Centre, Ljubljana, Slovenia * Corresponding author: Tel.: +386-1-543-73-81, E-mail: andrej.coer@mf.uni-lj.si |
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| Volume 9 (2004) pp 375-388 | |
| Title | APPLICATION OF THE ENSEMBLE NONEQUILIBRIUM RESPONSE SPECTROSCOPY TO SHAKER POTASSIUM CHANNEL GATING |
| Authors | Armin Kargol |
| Abstract | Standard electrophysiology techniques study relaxation transients in voltage-gated ion channels generated by discrete voltage steps. The nonequilibrium response spectroscopy involves analyzing responses to fluctuating potentials. We apply the ensemble NRS method to gating kinetics of Shaker potassium ion channels. We evaluate various proposed Markov models of channel gating from the nonequilibrium response viewpoint. These new NRS protocols can be used to test otherwise indistinguishable models or improve estimates for parameters of channel kinetics models. |
| Address and Contact Information | Loyola University, Department of Physics, 6363 St. Charles Ave., New Orleans,
LA 70118, USA |
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| Volume 9 (2004) pp 389-399 | |
| Title | THE IMPACT OF NEURAMINIDASE ON APOPTOSIS IN CULTURES OF BLOOD LYMPHOCYTES ISOLATED FROM RATS BEARING MORRIS HEPATOMA |
| Authors | Kazimierz Gąsiorowski1, Andrzej Steciwko2*, Urszula Grata-Borkowska2 and Jarosław Drobnik2 |
| Abstract | Lymphocytes were obtained by heart-punction from rats bearing Morris hepatoma. In the short term, 18-hour cultures of these lymphocytes exhibited a significantly higher amount of apoptotic cells than lymphocyte cultures from the healthy, control animals. Neuraminidase, injected into the caudal vein of the rats with Morris hepatoma, caused a marked lowering in the amount of apoptotic blood-lymphocytes and an elevation of the amount of viable cells. The possible mechanism of neuraminidase preventing the apoptosis of blood-circulating lymphocytes in tumour hosts is discussed herein. |
| Address and Contact Information | 1Department of Basic Medical Sciences, Wrocław Medical University,
Kochanowskiego 14, 51-601 Wrocław, Poland, 2Department of Family Medicine, Wrocław Medical University, Syrokomli 1, 51-141 Wrocław, Poland * Corresponding author, fax: 48 71 3254341, e-mail: zmr@zmr.am.wroc.pl. |
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