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Different Tissues (different + tissue)
Terms modified by Different Tissues Selected AbstractsOxygen-sensing pathway for SK channels in the ovine adrenal medullaCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 10 2005Damien J Keating SUMMARY 1.,The intracellular pathways that modulate the opening of oxygen-sensitive ion channels during periods of hypoxia are poorly understood. Different tissues appear to use either NADPH oxidase or a rotenone-sensitive mechanism as an oxygen sensor. The aim of the present study was to identify the oxygen-sensing pathway in the oxygen-sensitive sheep adrenal medullary chromaffin cell (AMCC). 2.,The whole-cell patch-clamp technique was used to measure K+ currents in dissociated adult ovine chromaffin cells as well as SK channel currents expressed in the H4IIE cell line. 3.,Diphenyliodonium, an inhibitor of NADPH oxidase, had no effect on the hypoxia-evoked closure of K+ channels in primary AMCC, whereas the mitochondrial inhibitor rotenone abolished the hypoxia-evoked response. Both these compounds significantly reduced K+ current amplitude under normoxic conditions. 4.,One possible mechanism through which the oxygen sensor may modulate K+ channel activity is by altering the redox state of the cell. In sheep AMCC, altering the redox state by the addition of H2O2 to the extracellular solution increased K+ conductance. 5.,The oxygen-sensitive K+ (Ko2) channels in sheep chromaffin cells are from the SK family and the whole-cell conductance of cells expressing mouse SK2 or SK3, but not human SK1, was increased by H2O2 and decreased by the reducing agent dithiothreitol. 6.,These studies show that, in sheep AMCC, Ko2 channels are modulated via a rotenone-sensitive mechanism and that alteration of the cellular redox state mimics the change produced by alterations in Po2. In a heterologous expression system, SK2 and SK3 channels, the channels that initiate hypoxia-evoked changes in AMCC function, are modulated appropriately by changes in cellular redox state. [source] Ultrastructural study of the temporomandibular joint after unilateral meniscectomy in Wistar ratsJOURNAL OF ORAL REHABILITATION, Issue 10 2006D. T. MARTINI summary, Meniscectomy of the temporomandibular joint (TMJ) was frequently performed until a few years ago but now is seldom employed. This procedure induces important articular modifications but the complete extent of ultrastructural changes is still unknown. Twenty-one Wistar rats were submitted to unilateral meniscectomy. Animals were randomly divided into three groups and followed for 15, 35 or 60 days. After killing both meniscectomized and contralateral TMJ specimens were sectioned sagittally and prepared for light and scanning electron microscopy studies. Normal TMJs are characterized by glenoid fossa and condylar process with distinct conjunctive layers in which regularly arranged type 1 collagen fibres predominate. Meniscectomized animals initially exhibit a different tissue covering the eroded articular surface of the condyle with the prevalence of type 3 collagen fibres but type 1 fibres predominate in the late postoperative period. Subchondral cysts are clearly visible. A complex remodelling process of the TMJ after meniscectomy is evident with important ultrastructural modifications that may correlate to unsatisfactory clinical results. The dynamic nature of this process is also observed when specimens from different postoperative periods are compared. Surgeons should always bear in mind these alterations when indicating this procedure. [source] Human peripheral blood B-cell compartments: A crossroad in B-cell traffic,CYTOMETRY, Issue S1 2010M. Perez-Andres Abstract A relatively high number of different subsets of B-cells are generated through the differentiation of early B-cell precursors into mature B-lymphocytes in the bone marrow (BM) and antigen-triggered maturation of germinal center B-cells into memory B-lymphocytes and plasmablasts in lymphoid tissues. These B-cell subpopulations, which are produced in the BM and lymphoid tissues, recirculate through peripheral blood (PB), into different tissues including mucosa and the BM, where long-living plasma cells produce antibodies. These circulating PB B-cells can be classified according to their maturation stage into i) immature/transitional, ii) naïve, and iii) memory B-lymphocytes, and iv) plasmablasts/plasma cells. Additionally, unique subsets of memory B-lymphocytes and plasmablasts/plasma cells can be identified based on their differential expression of unique Ig-heavy chain isotypes (e.g.: IgM, IgD, IgG, IgA). In the present paper, we review recent data reported in the literature about the distribution, immunophenotypic and functional characteristics of these cell subpopulations, as well as their distribution in PB according to age and seasonal changes. Additional information is also provided in this regard based on the study of a population-based cohort of 600 healthy adults aged from 20 to 80 years, recruited in the Salamanca area in western Spain. Detailed knowledge of the distribution and traffic of B-cell subsets through PB mirrors the immune status of an individual subject and it may also contribute to a better understanding of B-cell disorders related to B-cell biology and homeostasis, such as monoclonal B-cell lymphocytosis (MBL). © 2010 International Clinical Cytometry Society [source] Good practice in head and neck fine needle aspiration cytology as assessed by CUSUMCYTOPATHOLOGY, Issue 6 2002I. A. Robinson Providing data as evidence of good practice is becoming imperative to meet the demands of professional revalidation and clinical governance. Sensitivity and specificity are common performance measures in fine needle aspiration (FNA) but are vulnerable to discordant analytical methods. We introduce a CUSUM technique and show how it may be used to show attainment and maintenance of proficiency in head and neck (H&N) FNA. In addition, we show how it can be used to compare practices and demonstrate different performance for FNAs from different tissues; a fact that must be recognized by anyone devising minimum performance values. [source] Lactoferrin and anti-lactoferrin antibodies: Effects of ironloading of lactoferrin on albumin extravasation in different tissues in ratsACTA PHYSIOLOGICA, Issue 1 2000Erga Lactoferrin is a cationic iron-binding protein, which is released from activated neutrophils in concert with reactive oxygen species. In vitro, lactoferrin has both anti- and proinflammatory effects; many of them dependent on iron-binding. In vivo, only iron-free lactoferrin reduced inflammatory hyperpermeability in the lung. We therefore examined whether 1 mg iron-free (Apo-Lf) or iron-saturated lactoferrin (Holo-Lf) alone or followed by anti-lactoferrin antibodies (aLf) affected permeability evaluated by extravasation of radiolabelled bovine serum albumin (CBSA) in different tissues of anaesthetized rats. Fifteen minutes after i.v. injection of Lf, aLf or saline was given and circulatory arrest was induced 20 min thereafter. Measurements were performed in control, after Apo-Lf, Holo-Lf, Apo-Lf + aLf, Holo-Lf + aLf and aLf alone (n=6,8 in each group). No intergroup differences were found for plasma volume and haematocrit at the start and end of the 37 min extravasation period or for total tissue water in any of the six different tissues studied, excluding larger transcapillary fluid shifts. However, increases in CBSA were seen without differences in tissue intravascular volume. Iron-free lactoferrin and aLf alone did not change CBSA significantly. Iron-saturated lactoferrin significantly increased CBSA in skin (neck), trachea and left ventricle of the heart to 249 ± 9, 284 ± 16 and 160 ± 7% of control, respectively. When followed by aLf, both Apo- and Holo-Lf increased CBSA significantly in four and five of the tissues studied, respectively. However, no significant effect was seen for Holo-Lf + aLf compared with Holo-Lf alone. In conclusion, iron-saturated, but not iron-free lactoferrin increased CBSA, whereas antilactoferrin increased CBSA compared with lactoferrin alone only when following iron-free lactoferrin. [source] Drosophila multiplexin (Dmp) modulates motor axon pathfinding accuracyDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 5 2009Frauke Meyer Multiplexins are multidomain collagens typically composed of an N-terminal thrombospondin-related domain, an interrupted triple helix and a C-terminal endostatin domain. They feature a clear regulatory function in the development of different tissues, which is chiefly conveyed by the endostatin domain. This domain can be found in proteolytically released monomeric and trimeric versions, and their diverse and opposed effects on the migratory behavior of epithelial and endothelial cell types have been demonstrated in cell culture experiments. The only Drosophila multiplexin displays specific features of both vertebrate multiplexins, collagens XV and XVIII. We characterized the Drosophila multiplexin (dmp) gene and found that three main isoforms are expressed from it, one of which is the monomeric endostatin version. Generation of dmp deletion alleles revealed that Dmp plays a role in motor axon pathfinding, as the mutants exhibit ventral bypass defects of the intersegmental nerve b (ISNb) similar to other motor axon guidance mutants. Transgenic overexpression of monomeric endostatin as well as of full-length Dmp, but not trimeric endostatin, were able to rescue these defects. In contrast, trimeric endostatin increased axon pathfinding accuracy in wild type background. We conclude that Dmp plays a modulating role in motor axon pathfinding and may be part of a buffering system that functions to avoid innervation errors. [source] Pigment cell distributions in different tissues of the zebrafish, with special reference to the striped pigment patternDEVELOPMENTAL DYNAMICS, Issue 2 2005Masashi Hirata Abstract The orderly pigment pattern of zebrafish (Danio rerio) is a good model system for studying how spatial patterns form in animals. Recent molecular genetic studies have shown that interactions between the pigment cells play major roles in pattern formation. In the present study, we performed comparative transmission electron microscopy of pigment cells, in order to clarify the structural interactions of pigment cells in tissues with and without a striped pattern. In patterned tissues, pigment cells were distributed as a one-cell-thick sheet. The layer order of the sheets is always kept strictly. In tissues without a striped pattern, the layer order was often disturbed or the cells were distributed in a scattered, double-sheeted, or an accumulated pile. Our observations suggest that the underlying mechanism that controls the vertical order of the pigment cells is related to that controlling the stripe pattern. Developmental Dynamics 234:293,300, 2005. © 2005 Wiley-Liss, Inc. [source] Molecular mechanisms of early gut organogenesis: A primer on development of the digestive tractDEVELOPMENTAL DYNAMICS, Issue 2 2003Julie C. Kiefer Abstract Creating an organ poses unique challenges in embryogenesis, including establishing an organ primordium and coordinating development of different tissues in the organ. The digestive tract (gut) is a complex organ system, posing the interesting question of how the development of a series of organs is coordinated to establish an organ system with a common function. Although gut development has been the focus of much research, the molecular mechanisms that regulate these events are just beginning to be understood. This primer will first outline the basic anatomy of the digestive tract and then focus on molecular mechanisms that drive vertebrate gut organogenesis. Deciphering mechanisms underlying gut organogenesis also provides insights into understanding the development of other organs. Developmental Dynamics 228:287,291, 2003. © 2003 Wiley-Liss, Inc. [source] Ci-GATAa, a GATA -class gene from the ascidian Ciona intestinalis: Isolation and developmental expressionDEVELOPMENTAL DYNAMICS, Issue 1 2003Palmira D'Ambrosio Abstract Members of the GATA family of zinc finger transcription factors have been shown to play important roles in controlling gene expression in a variety of cell types in many metazoan. Here, we describe the identification of Ci-GATAa, a member of this gene family, in the ascidian Ciona intestinalis. Whole-mount in situ hybridization showed that Ci-GATAa was expressed in a highly dynamic manner. The maternal transcript was evenly distributed in the embryo during early stages of development; however, the signal gradually decreased until it disappeared at the 64-cell stage. A zygotic transcript was detected at the 110-cell stage in the blastomeres precursors of three different tissues (brain vesicle, mesenchyme, and trunk lateral cells) and the signal was conserved in these territories up to the larval stage, indicating an important role for Ci-GATAa during ascidian differentiation. © 2002 Wiley-Liss, Inc. [source] Further characterization and validation of gpt delta transgenic mice for quantifying somatic mutations in vivoENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 4 2001Roy R. Swiger Abstract The utility of any mutation assay depends on its characteristics, which are best discovered using model mutagens. To this end, we report further on the characteristics of the lambda-based gpt delta transgenic assay first described by Nohmi et al. ([1996]: Environ Mol Mutagen 28:465,470). Our studies show that the gpt transgene responds similarly to other transgenic loci, specifically lacZ and cII, after treatment with acute doses of N -ethyl- N -nitrosourea (ENU). Because genetic neutrality is an important factor in the design of treatment protocols for mutagenicity testing, as well as for valid comparisons between different tissues and treatments, a time-course study was conducted. The results indicate that the gpt transgene, like cII and lacZ, is genetically neutral in vivo. The sensitivities of the loci are also equivalent, as evidenced by spontaneous mutant frequency data and dose, response curves after acute treatment with 50, 150, or 250 mg/kg ENU. The results are interesting in light of transgenic target size and location and of host genetic background differences. Based on these studies, protocols developed for other transgenic assays should be suitable for the gpt delta. Additionally, a comparison of the gpt and an endogenous locus, Dlb-1, within the small intestine of chronically treated animals (94 ,g/mL ENU in drinking water daily) shows differential accumulation of mutations at the loci during chronic exposure. The results further support the existence of preferential repair at endogenous, expressed genes relative to transgenes. Environ. Mol. Mutagen. 37:297,303, 2001 © 2001 Wiley-Liss, Inc. [source] Aluminum induces chromosome aberrations, micronuclei, and cell cycle dysfunction in root cells of Vicia fabaENVIRONMENTAL TOXICOLOGY, Issue 2 2010Min Yi Abstract Aluminum (Al) exists naturally in air, water, and soil, and also in our diet. Al can be absorbed into the human body and accumulates in different tissues, which has been linked to the occurrence of Alzheimer's disease and various neurological disorders. By using Vicia cytogenetic tests, which are commonly used to monitor the genotoxicity of environmental pollutants, cytogenetic effects of aluminum (AlCl3) were investigated in this study. Present results showed that Al caused significant increases in the frequencies of micronuclei (MN) and anaphase chromosome aberrations in Vicia faba root tips exposed to Al over a concentration-tested range of 0.01,10 mM for 12 h. The frequency of micronucleated cells was higher in Al-treated groups at pH 4.5 than that at pH 5.8. Similarly, AlCl3 treatment caused a decrease in the number of mitotic cells in a dose- and pH-dependent manner. The number of cells in each mitotic phase changed in Al-treated samples. Mitotic indices (MI) decreased with the increases of pycnotic cells. Our results demonstrate that aluminum chloride is a clear clastogenic/genotoxic and cytotoxic agent in Vicia root cells. The V. faba cytogenetic test could be used for the genotoxicity monitoring of aluminum water contamination. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2010. [source] Methylmercury uptake and distribution kinetics in sheepshead minnows, Cyprinodon variegatus, after exposure to CH3Hg-spiked foodENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2004Joy J. Leaner Abstract The distribution kinetics of methylmercury (CH3Hg[II]) was determined in sheepshead minnows (Cyprinodon variegatus) after a single dose of different CH3Hg(II)-spiked food to determine what factors influence the bioavailability, uptake, and redistribution of CH3Hg(II) to various organs of C. variegatus. The kinetics of CH3Hg(II) distribution was measured in the different organs during a period of 0.1 to 35 d after dosage. The CH3Hg(II) distribution kinetics in the different tissues was modeled using a simple multicompartmental pharmacokinetic model, which assumed that blood was the conduit linking the CH3Hg(II) exchange between the different organs. The CH3Hg(II) was taken up into the intestinal tissue within hours after feeding, followed by a slow release to the blood and the other organs of the body. Exchange between the blood and the visceral organs was relatively slow, with maximum CH3Hg(II) uptake in the liver and gill occurring at 1.5 d following dietary exposure. Subsequently, the majority of the CH3Hg(II) was channeled from the viscera to the rest of the body with a substantial lag time after feeding. However, the rate of transfer between tissues in the studies reported here were faster than those measured by others for larger fish. [source] A logical starting point for developing priorities for lizard and snake ecotoxicology: A review of available dataENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2002Kym Rouse Campbell Abstract Reptiles, specifically lizards and snakes, usually are excluded from environmental contamination studies and ecological risk assessments. This brief summary of available lizard and snake environmental contaminant data is presented to assist in the development of priorities for lizard and snake ecotoxicology. Most contaminant studies were not conducted recently, list animals found dead or dying after pesticide application, report residue concentrations after pesticide exposure, compare contaminant concentrations in animals from different areas, compare residue concentrations found in different tissues and organs, or compare changes in concentrations over time. The biological significance of the contaminant concentrations is rarely studied. A few recent studies, especially those conducted on modern pesticides, link the contaminant effects with exposure concentrations. Nondestructive sampling techniques for determining organic and inorganic contaminant concentrations in lizards and snakes recently have been developed. Studies that relate exposure, concentration, and effects of all types of environmental contaminants on lizards and snakes are needed. Because most lizards eat insects, studies on the exposure, effects, and accumulation of insecticides in lizards, and their predators, should be a top priority. Because all snakes are upper-trophic-level carnivores, studies on the accumulation and effects of contaminants that are known to bioaccumulate or biomagnify up the food chain should be the top priority. [source] Cloning and characterization of SDF-1,, a novel SDF-1 chemokine transcript with developmentally regulated expression in the nervous systemEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2000Marc Gleichmann Abstract The cytokines SDF-1, and -1, are two alternatively spliced variants of the CXC (,) chemokines that are highly conserved among species. SDF-1, was shown to function as a B-cell maturation factor, a ligand for the CXCR4 (LESTR/fusin) chemokine receptor, thereby inhibiting replication of T cell-tropic HIV-1 strains and inducing cell death in human neuronal cell lines. In this report the cloning of the rat SDF-1, cDNA and a new SDF-1 isoform, SDF-1,, are presented. Using Northern blot analysis, the expression pattern of both isoforms was studied in different tissues and it is shown that during postnatal development of the central and peripheral nervous system SDF-1,- and SDF-1,-mRNA expression is inversely regulated. Whilst SDF-1,-mRNA is the predominant isoform in embryonic and early postnatal nerve tissue, SDF-1,-mRNA is expressed at higher levels in adulthood. After peripheral nerve lesion a transient increase in SDF-1,-mRNA expression is observed. As revealed by in situ hybridization, neurons and Schwann cells are the main cellular sources of both SDF-1, and SDF-1, mRNAs in the nervous system. Computer-assisted analysis revealed that both transcripts encode secreted peptides with putative proteolytic cleavage sites which might generate novel neuropeptides. [source] A TEST OF THE NEUTRAL MODEL OF EXPRESSION CHANGE IN NATURAL POPULATIONS OF HOUSE MOUSE SUBSPECIESEVOLUTION, Issue 2 2010Fabian Staubach Changes in expression of genes are thought to contribute significantly to evolutionary divergence. To study the relative role of selection and neutrality in shaping expression changes, we analyzed 24 genes in three different tissues of the house mouse (Mus musculus). Samples from two natural populations of the subspecies M. m. domesticus and M. m. musculus were investigated using quantitative PCR assays and sequencing of the upstream region. We have developed an approach to quantify expression polymorphism within such populations and to disentangle technical from biological variation in the data. We found a correlation between expression polymorphism within populations and divergence between populations. Furthermore, we found a correlation between expression polymorphism and sequence polymorphism of the respective genes. These data are most easily interpreted within a framework of a predominantly neutral model of gene expression change, where only a fraction of the changes may have been driven by positive selection. Although most genes investigated were expressed in all three tissues analyzed, significant changes of expression levels occurred predominantly in a single tissue only. This adds to the notion that enhancer-specific effects or transregulatory effects can modulate the evolution of gene expression in a tissue-specific way. [source] Development and evolution of adaptive polyphenismsEVOLUTION AND DEVELOPMENT, Issue 1 2003H. Frederik Nijhout SUMMARY Phenotypic plasticity is the primitive character state for most if not all traits. Insofar as developmental and physiological processes obey the laws of chemistry and physics, they will be sensitive to such environmental variables as temperature, nutrient supply, ionic environment, and the availability of various macro- and micronutrients. Depending on the effect this phenotypic plasticity has on fitness, evolution may proceed to select either for mechanisms that buffer or canalize the phenotype against relevant environmental variation or for a modified plastic response in which some ranges of the phenotypic variation are adaptive to particular environments. Phenotypic plasticity can be continuous, in which case it is called a reaction norm, or discontinuous, in which case it is called a polyphenism. Although the morphological discontinuity of some polyphenisms is produced by discrete developmental switches, most polyphenisms are due to discontinuities in the environment that induce only portions of what is in reality a continuous reaction norm. In insect polyphenisms, the environmental variable that induces the alternative phenotype is a token stimulus that serves as a predictor of, but is not itself, the environment to which the polyphenism is an adaptation. In all cases studied so far, the environmental stimulus alters the endocrine mechanism of metamorphosis by altering either the pattern of hormone secretion or the pattern of hormone sensitivity in different tissues. Such changes in the patterns of endocrine interactions result in the execution of alternative developmental pathways. The spatial and temporal compartmentalization of endocrine interactions has produced a developmental mechanism that enables substantial localized changes in morphology that remain well integrated into the structure and function of the organism. [source] Hormones as epigenetic signals in developmental programmingEXPERIMENTAL PHYSIOLOGY, Issue 6 2009Abigail L. Fowden In mammals, including man, epidemiological and experimental studies have shown that a range of environmental factors acting during critical periods of early development can alter adult phenotype. Hormones have an important role in these epigenetic modifications and can signal the type, severity and duration of the environmental cue to the developing feto-placental tissues. They affect development of these tissues both directly and indirectly by changes in placental phenotype. They act to alter gene expression, hence the protein abundance in a wide range of different tissues, which has functional consequences for many physiological systems both before and after birth. By producing an epigenome specific to the prevailing condition in utero, hormones act as epigenetic signals in developmental programming, with important implications for adult health and disease. This review examines the role of hormones as epigenetic signals by considering their responses to environmental cues, their effects on phenotypical development and the molecular mechanisms by which they programme feto-placental development, with particular emphasis on the glucocorticoids. [source] Genome-wide identification, classification, evolutionary expansion and expression analyses of homeobox genes in riceFEBS JOURNAL, Issue 11 2008Mukesh Jain Homeobox genes play a critical role in regulating various aspects of plant growth and development. In the present study, we identified a total of 107 homeobox genes in the rice genome and grouped them into ten distinct subfamilies based upon their domain composition and phylogenetic analysis. A significantly large number of homeobox genes are located in the duplicated segments of the rice genome, which suggests that the expansion of homeobox gene family, in large part, might have occurred due to segmental duplications in rice. Furthermore, microarray analysis was performed to elucidate the expression profiles of these genes in different tissues and during various stages of vegetative and reproductive development. Several genes with predominant expression during various stages of panicle and seed development were identified. At least 37 homeobox genes were found to be differentially expressed significantly (more than two-fold; P < 0.05) under various abiotic stress conditions. The results of the study suggest a critical role of homeobox genes in reproductive development and abiotic stress signaling in rice, and will facilitate the selection of candidate genes of agronomic importance for functional validation. [source] A gene duplication led to specialized ,-aminobutyrate and ,-alanine aminotransferase in yeastFEBS JOURNAL, Issue 7 2007Gorm Andersen In humans, ,-alanine (BAL) and the neurotransmitter ,-aminobutyrate (GABA) are transaminated by a single aminotransferase enzyme. Apparently, yeast originally also had a single enzyme, but the corresponding gene was duplicated in the Saccharomyces kluyveri lineage. SkUGA1 encodes a homologue of Saccharomyces cerevisiae GABA aminotransferase, and SkPYD4 encodes an enzyme involved in both BAL and GABA transamination. SkPYD4 and SkUGA1 as well as S. cerevisiaeUGA1 and Schizosaccharomyces pombeUGA1 were subcloned, over-expressed and purified. One discontinuous and two continuous coupled assays were used to characterize the substrate specificity and kinetic parameters of the four enzymes. It was found that the cofactor pyridoxal 5,-phosphate is needed for enzymatic activity and ,-ketoglutarate, and not pyruvate, as the amino group acceptor. SkPyd4p preferentially uses BAL as the amino group donor (Vmax/Km = 0.78 U·mg,1·mm,1), but can also use GABA (Vmax/Km = 0.42 U·mg,1·mm,1), while SkUga1p only uses GABA (Vmax/Km = 4.01 U·mg,1·mm,1). SpUga1p and ScUga1p transaminate only GABA and not BAL. While mammals degrade BAL and GABA with only one enzyme, but in different tissues, S. kluyveri and related yeasts have two different genes/enzymes to apparently ,distinguish' between the two reactions in a single cell. It is likely that upon duplication ,200 million years ago, a specialized Uga1p evolved into a ,novel' transaminase enzyme with broader substrate specificity. [source] Identification of a cowpea ,-thionin with bactericidal activityFEBS JOURNAL, Issue 15 2006Octávio L. Franco Antimicrobial peptides are an abundant group of proteinaceous compounds widely produced in the plant kingdom. Among them, the ,-thionin family, also known as plant defensins, represents one typical family and comprises low molecular mass cysteine-rich proteins, usually cationic and distributed in different plant tissues. Here, we report the purification and characterization of a novel ,-thionin from cowpea seeds (Vigna unguiculata), named Cp-thionin II, with bactericidal activity against Gram-positive and Gram-negative bacteria. Once the primary structure was elucidated, molecular modelling experiments were used to investigate the multimerization and mechanism of action of plant ,-thionins. Furthermore, Cp-thionin II was also localized in different tissues in cowpea seedlings during germination in contrasting conditions, to better understand the plant protection processes. The use of plant defensins in the construction of transgenic plants and also in the production of novel drugs with activity against human pathogens is discussed. [source] Molecular and functional characterization of a novel splice variant of ANKHD1 that lacks the KH domain and its role in cell survival and apoptosiscFEBS JOURNAL, Issue 16 2005Melissa C. Miles Multiple ankyrin repeat motif-containing proteins play an important role in protein,protein interactions. ANKHD1 proteins are known to possess multiple ankyrin repeat domains and a single KH domain with no known function. Using yeast two-hybrid system analysis, we identified a novel splice variant of ANKHD1. This splice variant of ANKHD1, which we designated as HIV-1 Vpr-binding ankyrin repeat protein (VBARP), does not contain the signature KH domain, and codes for only a single ankyrin repeat motif. We characterized VBARP by molecular and functional analysis, revealing that VBARP is ubiquitously expressed in different tissues as well as cell lines of different lineage. In addition, blast searches indicated that orthologs and homologs to VBARP exist in different phyla, suggesting that VBARP might be evolutionarily conserved, and thus may be involved in basic cellular function(s). Furthermore, biochemical analysis revealed the presence of two VBARP isoforms coding for 69 and 49 kDa polypeptides, respectively, that are primarily localized in the cytoplasm. Functional analysis using short interfering RNA approaches indicate that this gene product is essential for cell survival through its regulation of caspases. Taken together, these results indicate that VBARP is a novel splice variant of ANKHD1 and may play a role in cellular apoptosis (antiapoptotic) and cell survival pathway(s). [source] Synchronized transcriptional gene expression of H+ -ATP synthase subunits in different tissues of Fischer 344 rats of different agesFEBS JOURNAL, Issue 23 2000Toshiki Himeda Little is known about the relationship between the stoichiometry of polypeptides of multisubunit enzyme complexes and the absolute amount of each transcript of the complexes in mammalian tissues. Here we showed that the absolute amounts of the transcripts of most subunits of rat H+ -ATP synthase examined greatly differed in the different tissues, showing the following hierarchy of tissue-specificity: heart > kidney > brain , liver. However, surprisingly, there was no difference in the expression pattern of these in terms of the molar ratio of each transcript, indicating a nearly similar stoichiometric expression pattern irrespective of tissue or age of the rat. Therefore, the present finding clearly indicates that most of the transcripts of the 16 subunits of rat H+ -ATP synthase were concertedly and synchronously expressed, having a constant expression pattern of the transcripts, irrespective of tissue or age of the rats. This is the first report of the absolute amounts of the transcripts of this multisubunit enzyme. [source] Non-receptor tyrosine kinase CSK-1 controls pharyngeal muscle organization in Caenorhabditis elegansGENES TO CELLS, Issue 3 2009Nozomu Takata C-terminal Src kinase (Csk) is a non-receptor type of tyrosine kinase, and serves as an essential negative regulator of Src family tyrosine kinases (SFKs) in vertebrates. However, analyses of Csk and SFKs from primitive animals suggest that the Csk-mediated mechanisms regulating SFK activity might diverge between evolutional branches, different tissues or SFK family members. We examined in vivo roles of CSK-1, a Caenorhabditis elegans orthologue of Csk, by generating animals lacking csk-1 function. Although some csk-1 mutants died during embryogenesis, the majority of mutants died during the first stage of larval development. In csk-1 mutants, the function of pharyngeal muscles, the major site of CSK-1 expression, was severely damaged. The pumping of pharyngeal grinder cells became arrhythmic, causing disabled feeding. Electron microscopy showed that pharyngeal muscle filaments were disorientated in the csk-1 mutants. These indicate that CSK-1 is crucial for proper organization of pharyngeal muscles. However, the growth arrest phenotype in csk-1 mutants could not be suppressed by src-1 and/or src-2 mutation, and SRC-1 was not significantly activated in the csk-1 mutants. These results suggest that CSK-1 has an essential function in organization of pharyngeal muscle filaments that does not require C. elegans SFKs. [source] DNA methylation variation in cloned miceGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 2 2001Jun Ohgane Abstract Summary: Mammalian cloning has been accomplished in several mammalian species by nuclear transfer. However, the production rate of cloned animals is quite low, and many cloned offspring die or show abnormal symptoms. A possible cause of the low success rate of cloning and abnormal symptoms in many cloned animals is the incomplete reestablishment of DNA methylation after nuclear transfer. We first analyzed tissue-specific methylation patterns in the placenta, skin, and kidney of normal B6D2F1 mice. There were seven spots/CpG islands (0.5% of the total CpG islands detected) methylated differently in the three different tissues examined. In the placenta and skin of two cloned fetuses, a total of four CpG islands were aberrantly methylated or unmethylated. Interestingly, three of these four loci corresponded to the tissue-specific loci in the normal control fetuses. The extent of aberrant methylation of genomic DNA varied between the cloned animals. In cloned animals, aberrant methylation occurred mainly at tissue-specific methylated loci. Individual cloned animals have different methylation aberrations. In other words, cloned animals are by no means perfect copies of the original animals as far as the methylation status of genomic DNA is concerned. genesis 30:45,50, 2001. © 2001 Wiley-Liss, Inc. [source] Protection against Fas-induced liver apoptosis in transgenic mice expressing cyclooxygenase 2 in hepatocytes,HEPATOLOGY, Issue 3 2007Marta Casado Cyclooxygenase-2 (COX-2) is upregulated in many cancers, and the prostanoids synthesized increase proliferation, improve angiogenesis, and inhibit apoptosis in several tissues. To explore the function of COX-2 in liver, transgenic (Tg) mice were generated containing a fusion gene (LIVhCOX-2) consisting of human COX-2 cDNA under the control of the human ApoE promoter. Six lines were developed; all of them expressed the LIVhCOX-2 transgene selectively in hepatocytes. The Tg mice exhibited a normal phenotype, and the increased levels of PGE2 found were due to the constitutively expressed COX-2. Histological analysis of different tissues and macroscopic examination of the liver showed no differences between wild-type (Wt) and Tg animals. However, Tg animals were resistant to Fas-mediated liver injury, as demonstrated by low levels of plasmatic aminotransferases, a lesser caspase-3 activation, and Bax levels and an increase in Bcl-2, Mcl-1, and xIAP proteins, when compared with the Wt animals. Moreover, the resistance to Fas-mediated apoptosis is suppressed in the presence of COX-2,selective inhibitors, which prevented prostaglandin accumulation in the liver of Tg mice. Conclusion: These results demonstrate that expression of COX-2,dependent prostaglandins exerted a protection against liver apoptosis. (HEPATOLOGY 2007;45:631,638.) [source] Aldehyde-Amine Chemistry Enables Modulated Biosealants with Tissue-Specific AdhesionADVANCED MATERIALS, Issue 32-33 2009Natalie Artzi The interfacial regions between PEG: dextran-based adhesive sealant and excised rat heart, lung, liver, and duodenum tissues exhibit three distinct domains; target tissue (red and blue), bulk material (green), and an adhesive regime interposed between the two. The variation in adhesive regime morphology when applied to different tissues provides a rational approach for the engineering of application-specific surgical sealants. [source] ANALYSIS OF THE SOLUBLE PROTEINS IN THREE SPECIES OF PARASITOIDS AND MOLECULAR CHARACTERISTICS OF YOLK PROTEIN IN PTEROMALUS PUPARUM,INSECT SCIENCE, Issue 4 2001SUN Meng Abstract The results both from PAGE and capillary electrophoresis indicated that there was a female specific protein i.e. vitellogenin (Vg) or vitellin (Vt) in the female wasp of Pteromalus puparum (Hymenoptera: Pteromalidae). While there was no difference in the electrophoresis graph between soluble proteins of the female whole body and those of the male one both in two bracoids (Hymenoptera: Braconidae), i.e. Cotesia plutellae and Macrocentrus linears. According to the graph of the gradient SDS-PAGE, it was clear that the Vg or Vt of P. puparum consisted of two subunits with approximate molecular weights, and their molecular weights were 74.4 and 52.8 KDa, respectively. Both immunological reactions between some main different tissues of the female wasps and the male whole body and the polyantibody against the Vt of this parasitoid, and the graph of the gradient SDS-PAGE including soluble proteins sampled separately from hemolymph, fat body and ovary of the female and the whole body of the male demonstrated that Vg existed both in female fat body and hemolymph, and Vt deposited in the ovary, not in the male, as well as the Vg was synthesized in the female fat body. [source] Photoperiod-induced apoptosis in the male genital tract epithelia of the golden hamsterINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 2 2007Rosa Carballada Summary The aim of this study was to identify some details of the changes induced by a short-day light regime (8:16 light:dark) on the male genital tract and accessory sex glands of the golden hamster Mesocricetus auratus. We principally examined the presence of apoptotic cells in the epithelium from different regions of the epididymis, seminal vesicles, prostate and coagulating gland. We detected an increase in the percentage of apoptotic cells in situ using the TUNEL technique in animals that were maintained for 6, 8 or 12 weeks in a short photoperiod. That those cells were indeed undergoing apoptosis was confirmed by the immunodetection of the active fragment of caspase-3. The apoptotic indices in the different tissues analysed were low, but were maintained for weeks, suggesting cell loss at a steady rate. We tried to correlate these changes with the testosterone levels in serum as well as with the oxidative stress in the tissue. On the other hand, the increase in size and number of lipofuscin granules indicated the possibility that a parallel increase in oxidative stress occurred in the tissues. The normalization in the number of apoptotic cells and lipofuscin granules in animals treated with testosterone suggests that both phenomena might be related to changes in the hormone levels. [source] Human BLCAP transcript: new editing events in normal and cancerous tissuesINTERNATIONAL JOURNAL OF CANCER, Issue 1 2010Federica Galeano Abstract Bladder cancer-associated protein (BLCAP) is a highly conserved protein among species, and it is considered a novel candidate tumor suppressor gene originally identified from human bladder carcinoma. However, little is known about the regulation or the function of this protein. Here, we show that the human BLCAP transcript undergoes multiple A-to-I editing events. Some of the new editing events alter the highly conserved amino terminus of the protein creating alternative protein isoforms by changing the genetically coded amino acids. We found that both ADAR1 and ADAR2-editing enzymes cooperate to edit this transcript and that different tissues displayed distinctive ratios of edited and unedited BLCAP transcripts. Moreover, we observed a general decrease in BLCAP -editing level in astrocytomas, bladder cancer and colorectal cancer when compared with the related normal tissues. The newly identified editing events, found to be downregulated in cancers, could be useful for future studies as a diagnostic tool to distinguish malignancies or epigenetic changes in different tumors. [source] Fabry Disease: Treatment and diagnosisIUBMB LIFE, Issue 11 2009Paula A. Rozenfeld Abstract Fabry disease is an X-linked lysosomal disorder that results from a deficiency of the lysosomal enzyme ,-galactosidase A leading to accumulation of glycolipids, mainly globotriaosylceramide in the cells from different tissues. Classical Fabry disease affects various organs. Clinical manifestations start at early age and include angiokeratoma, acroparesthesia, hypohydrosis, heat/exercise intolerance, gastrointestinal pain, diarrhea, and fever. The main complications of Fabry disease are more prominent after the age of 30 when kidney, heart, and/or cerebrovascular disorders appear. Most of the heterozygous females are symptomatic. Enzyme replacement therapy (ERT) is the only specific treatment for Fabry disease. The beneficial effect of ERT on different organs/systems has been extensively evaluated. Quality of life of patients receiving ERT is improved. Enzyme replacement stabilizes or slows the decline in renal function and reduces left ventricular hypertrophy. Fabry disease may be underdiagnosed because of nonspecific and multiorgan symptoms. Different screening strategies have been carried out in different at-risk populations in order to detect undiagnosed Fabry patients. An increasing knowledge about Fabry disease within the medical community increases the chances of patients to receive a timely diagnosis and, consequently, to access the appropriate therapy. © 2009 IUBMB IUBMB Life, 61(11): 1043,1050, 2009 [source] |