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Author (up) Arimoto-Kobayashi, S.; Sakata, H.; Mitsu, K.; Tanoue, H. file  url
openurl 
  Title A possible photosensitizer: Tobacco-specific nitrosamine, 4-(N-methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), induced mutations, DNA strand breaks and oxidative and methylative damage with UVA Type Journal Article
  Year 2007 Publication Mutation Research Abbreviated Journal Mutat Res  
  Volume 632 Issue 1-2 Pages 111-120  
  Keywords Base Sequence; DNA Breaks; DNA Methylation--drug effects, radiation effects; Dose-Response Relationship, Drug; Models, Biological; Molecular Sequence Data; Mutation; Nitrosamines--toxicity; Oxidative Stress--drug effects, radiation effects; Photosensitizing Agents--toxicity; Salmonella typhimurium; Tobacco--chemistry; Ultraviolet Rays--adverse effects  
  Abstract We discovered the directly acting mutagenicity of the tobacco-specific nitrosamine, 4-(N-methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), with UVA light (320-400nm) in Ames bacteria and phage M13mp2 in the absence of metabolic activation. We have investigated the spectrum of mutations caused by UVA-activated NNK. The majority (57%) of induced sequence changes were comprised of GC to CG, GC to TA and GC to AT. This suggested that modification of guanine residues was responsible for these mutations. Hence, we explored the formation of 7,8-dihydro-8-oxo-2'-deoxyguanosine (8-oxodG) and O(6)-methylguanine (O(6)meG) in the DNA. When calf thymus DNA was treated with NNK and UVA, the amount of 8-oxodG/dG and O(6)meG/G in the DNA increased up to 20-fold and 100-fold, respectively, compared with the untreated control. DNA strand breaks were observed following NNK and UVA treatment, and the strand breaks were suppressed in the presence of scavengers for oxygen and NO radical. The formation of NO was also observed in NNK solutions irradiated with UVA. We analyzed the photodynamic spectrum of mutation induction, 8-oxodG formation and NO formation using monochromatic radiation. The patterns of the action spectra were comparable to the absorption spectrum of NNK. We conclude that NNK may act as a photosensitizer in response to UVA to produce NO and other oxidative and alkylative intermediates following the formation of 8-oxodG and O(6)meG in DNA, which may lead to mutations and DNA strand breaks.  
  Call Number Serial 86  
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Author (up) Aveskamp, M.M.; Verkley, G.J.M.; de Gruyter, J.; Murace, M.A.; Perello, A.; Woudenberg, J.H.C.; Groenewald, J.Z.; Crous, P.W. file  url
openurl 
  Title DNA phylogeny reveals polyphyly of Phoma section Peyronellaea and multiple taxonomic novelties Type Journal Article
  Year 2009 Publication Mycologia Abbreviated Journal Mycologia  
  Volume 101 Issue 3 Pages 363-382  
  Keywords Actins/analysis/genetics; Ascomycota/*classification/cytology/genetics; Biodiversity; DNA, Fungal/*analysis/genetics; DNA, Ribosomal Spacer/analysis/genetics; Genetic Speciation; Genetic Variation; Molecular Sequence Data; *Phylogeny; Polymerase Chain Reaction; Sequence Alignment; Sequence Analysis, DNA; Species Specificity; Tubulin/analysis/genetics  
  Abstract Species of the anamorph genus Phoma are commonly isolated from a wide range of ecological niches. They are notoriously difficult to identify due to the paucity of morphological features and the plasticity of these when cultivated on agar media. Species linked to Phoma section Peyronellaea are typified by the production of dictyochlamydospores and thus have additional characters to use in taxon delineation. However, the taxonomy of this section is still not fully understood. Furthermore the production of such chlamydospores also is known in some other sections of Phoma. DNA sequences were generated from three loci, namely ITS, actin, and 3-tubulin, to clarify the phylogeny of Phoma taxa that produce dictyochlamydospores. Results were unable to support section Peyronellaea as a taxonomic entity. Dictyochlamydospore formation appears to be a feature that developed, or was lost, many times during the evolution of Phoma. Furthermore, based on the multigene analyses, five new Phoma species could be delineated while a further five required taxonomic revision to be consistent with the genetic variation observed.  
  Call Number Serial 1999  
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Author (up) Baylis, H.A.; Furuichi, T.; Yoshikawa, F.; Mikoshiba, K.; Sattelle, D.B. file  url
openurl 
  Title Inositol 1,4,5-trisphosphate receptors are strongly expressed in the nervous system, pharynx, intestine, gonad and excretory cell of Caenorhabditis elegans and are encoded by a single gene (itr-1) Type Journal Article
  Year 1999 Publication Journal of Molecular Biology Abbreviated Journal J Mol Biol  
  Volume 294 Issue 2 Pages 467-476  
  Keywords Amino Acid Sequence; Animals; Animals, Genetically Modified; Binding Sites; Caenorhabditis elegans/*genetics; Calcium Channels/*genetics/*metabolism; Cell Membrane/genetics/metabolism; Conserved Sequence; Gene Expression Profiling; Gonads/metabolism; Helminth Proteins/*genetics/*metabolism; Inositol 1,4,5-Trisphosphate Receptors; Intestines/metabolism; Molecular Sequence Data; Nervous System/metabolism; Pharynx/metabolism; RNA, Messenger; Receptors, Cytoplasmic and Nuclear/*genetics/*metabolism; Rectum/cytology/metabolism  
  Abstract Inositol 1,4,5-trisphosphate (InsP3) activates receptors (InsP3Rs) that mediate intracellular Ca(2+ )release, thereby modulating intracellular calcium signals and regulating important aspects of cellular physiology and gene expression. To further our understanding of InsP3Rs we have characterised InsP3Rs and the InsP3R gene, itr-1, from the model organism Caenorhabditis elegans. cDNAs encoding InsP3Rs were cloned enabling us to: (a) identify three putative transcription start sites that result in alternative mRNA 5' ends: (b) detect alternative splicing at three sites and: (c) determine the full genomic organisation of the itr-1 gene. The InsP3R protein (ITR-1) is approximately 42 % identical with known InsP3Rs and possesses conserved structural features. When the putative InsP3 binding domain was expressed in Escherichia coli, specific binding of InsP3 was detected. Using antibodies against ITR-1 we detected a protein of 220 kDa in C. elegans membranes. These antibodies and itr-1::GFP (green fluorescent protein) reporter constructs were used to determine the expression pattern of itr-1 in C. elegans. Strong expression was observed in the intestine, pharynx, nerve ring, excretory cell and gonad. These results demonstrate the high degree of structural and functional conservation of InsP3Rs from nematodes to mammals and the utility of C. elegans as a system for studies on InsP3R mediated signalling.  
  Call Number Serial 309  
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Author (up) Birchall, P.S.; Fishpool, R.M.; Albertson, D.G. file  url
openurl 
  Title Expression patterns of predicted genes from the C. elegans genome sequence visualized by FISH in whole organisms Type Journal Article
  Year 1995 Publication Nature Genetics Abbreviated Journal Nat Genet  
  Volume 11 Issue 3 Pages 314-320  
  Keywords Animals; Base Sequence; Caenorhabditis/cytology/*genetics; *Gene Expression; *Genome; Helminth Proteins/genetics; In Situ Hybridization, Fluorescence/*methods; Molecular Sequence Data; Muscle Proteins/genetics; RNA, Messenger/analysis  
  Abstract More than 10 megabases of contiguous genome sequence have been submitted to the databases by the Caenorhabditis elegans Genome Sequencing Consortium. To characterize the genes predicted from the sequence, we have developed high resolution FISH for visualization of mRNA distributions in whole animals. The high resolution and sensitivity afforded by the use of directly fluorescently labelled probes and confocal imaging permitted mRNA distributions to be recorded at the cellular and subcellular level. Expression patterns were obtained for 8 out of 10 genes in an initial test set of predicted gene sequences, indicating that FISH is an effective means of characterizing predicted genes in C. elegans.  
  Call Number Serial 172  
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Author (up) Cho, J.H.; Bandyopadhyay, J.; Lee, J.; Park, C.S.; Ahnn, J. file  url
openurl 
  Title Two isoforms of sarco/endoplasmic reticulum calcium ATPase (SERCA) are essential in Caenorhabditis elegans Type Journal Article
  Year 2000 Publication Gene Abbreviated Journal Gene  
  Volume 261 Issue 2 Pages 211-219  
  Keywords Alternative Splicing; Amino Acid Sequence; Animals; Caenorhabditis elegans/embryology/enzymology/*genetics; Calcium-Transporting ATPases/*genetics/metabolism; Embryo, Nonmammalian/drug effects/enzymology; Embryonic Development; Gene Expression Regulation, Enzymologic; Green Fluorescent Proteins; Isoenzymes/genetics/metabolism; Luminescent Proteins/genetics/metabolism; Microscopy, Fluorescence; Molecular Sequence Data; Phenotype; Promoter Regions, Genetic/genetics; RNA, Double-Stranded/administration & dosage/genetics; Recombinant Fusion Proteins/genetics/metabolism; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Sequence Homology, Amino Acid; Tissue Distribution  
  Abstract SERCA (Sarco/Endoplasmic Reticulum Calcium ATPase), a membrane bound Ca(2+)- /Mg(2+)- dependent ATPase that sequesters Ca(2+) into the SR/ER lumen, is one of the essential components for the maintenance of intracellular Ca(2+) homeostasis. Here we describe the identification and functional characterization of a C. elegans SERCA gene (ser-1). ser-1 is a single gene alternatively spliced at its carboxyl terminus to form two isoforms (SER-1A and SER-1B) and displays a high homology (70% identity, 80% similarity) with mammalian SERCAs. Green fluorescent protein (GFP) and whole-mount immunostaining analyses reveal that SER-1 expresses in neuronal cells, body-wall muscles, pharyngeal and vulval muscles, excretory cells, and vulva epithelial cells. Furthermore, SER-1::GFP expresses during embryonic stages and the expression is maintained through the adult stages. Double-stranded RNA injection (also known as RNAi) targeted to each SER-1 isoform results in severe phenotypic defects: ser-1A(RNAi) animals show embryonic lethality, whereas ser-1B(RNAi) results in L1 larval arrest phenotype. These findings suggest that both isoforms of C. elegans SERCA, like in mammals, are essential for embryonic development and post-embryonic growth and survival.  
  Call Number Serial 451  
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