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Kan Fujino Masayuki Horie Tomoyuki Honda Shoko Nakamura Yusuke Matsumoto Ivo M. B. Francischetti Keizo Tomonaga 《PloS one》2012,7(12)
Bornavirus, a non-segmented, negative-strand RNA viruses, is currently classified into several genetically distinct genotypes, such as Borna disease virus (BDV) and avian bornaviruses (ABVs). Recent studies revealed that bornavirus genotypes show unique sequence variability in the putative 5′ untranslated region (5′ UTR) of X/P mRNA, a bicistronic mRNA for the X protein and phosphoprotein (P). In this study, to understand the evolutionary relationship among the bornavirus genotypes, we investigated the functional interaction between the X and P proteins of four bornavirus genotypes, BDV, ABV genotype 4 and 5 and reptile bornavirus (RBV), the putative 5′ UTRs of which exhibit variation in the length. Immunofluorescence and immunoprecipitation analyses using mammalian and avian cell lines revealed that the X proteins of bornaviruses conserve the ability to facilitate the export of P from the nucleus to the cytoplasm via interaction with P. Furthermore, we showed that inter-genotypic interactions may occur between X and P among the genotypes, except for X of RBV. In addition, a BDV minireplicon assay demonstrated that the X and P proteins of ABVs, but not RBV, can affect the polymerase activity of BDV. This study demonstrates that bornaviruses may have conserved the fundamental function of a regulatory protein during their evolution, whereas RBV has evolved distinctly from the other bornavirus genotypes. 相似文献
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Host discrimination modulates brood guarding behaviour and the adaptive superparasitism in the parasitoid wasp Trissolcus semistriatus (Hymenoptera: Scelionidae) 下载免费PDF全文
Because hosts utilized by parasitoids are vulnerable to further oviposition by conspecifics, host guarding benefits female wasps. The present study aims to test whether female adults regulate brood guarding behaviour by host discrimination in a solitary parasitoid Trissolcus semistriatus by presenting an intact or parasitized host egg mass to a female adult. Virgin females without oviposition experience have host discrimination ability, which enables them to adjust the number of eggs laid in the hosts. Mating experience increases superparasitism by female adults, whereas mated females achieve a higher discrimination ability as a result of oviposition experience and show a lower superparasitism rate. As expected, females exhibit brood guard after parasitizing an intact host egg mass, whereas those females visiting a previously parasitized host egg mass, do not. Because the survival of eggs in superparasitized hosts is relatively low, regulating brood guarding behaviour by host discrimination is adaptive for female wasps. 相似文献
5.
Galectin-3 is a β-galactoside-binding C-type lectin that plays an important role in innate immunity. The purpose of this study was to determine whether Candida albicans and Candida parapsilosis up-regulate galectin-3 secretion by human gingival epithelial cells and gingival fibroblasts. Ca9-22, a human gingival epithelial cell line, and human gingival fibroblasts were incubated in the presence or absence of C. albicans or C. parapsilosis without serum. Levels of secreted human galectin-3 in culture supernatants were measured by enzyme-linked immunosorbent assay. We also pretreated Ca9-22 cells with cytochalasin D (an actin polymerization inhibitor), ALLN (a calpain inhibitor) and LY294002 [a phosphatidylinositol-3 kinase (PI3K) inhibitor] to determine whether the up-regulation of galectin-3 secretion was mediated by cytoskeletal changes, protease activity, or PI3K signaling. Galectin-3 secretion was significantly and rapidly up-regulated by live C. albicans and C. parapsilosis, as well as heat-killed C. albicans. In addition, cytochalasin D, LY294002 and ALLN did not inhibit the up-regulation in galectin-3 secretion. These results suggest that both live and heat-killed C. albicans and C. parapsilosis may increase the activity of the innate immune system and invasion by other microorganisms via up-regulation of galectin-3 secretion. 相似文献
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Yusuke Nakamura Michio Ogawa Takahiro Nishide Mitsuru Emi Goro Kosaki Seiichi Himeno Kenichi Matsubara 《Gene》1984,28(2):263-270
The nucleotide sequences of the cloned human salivary and pancreatic α-amylase cDNAs correspond to the continuous mRNA sequences of 1768 and 1566 nucleotides, respectively. These include all of the amino acid coding regions. Salivary cDNA contains 200 bp in the 5′-noncoding region and 32 in the 3′-noncoding region. Pancreatic cDNA contains 3 and 27 bp of 5′- and 3′-noncoding regions, respectively. The nucleotide sequence humology of the two cDNAs is 96% in the coding region, and the predicted amino acid sequences are 94% homologous.Comparison of the sequences of human α-amylase cDNAs with those previously obtained for mouse α-amylase genes (Hagenbuchle et al., 1980; Schibler et al., 1982) showed the possibility of gene conversion between the two genes of human α-amylase. 相似文献
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Aspartase of Escherichia coli was inhibited in a competitive manner by S-2,3-dicarboxyazirdine (DCAZ), an antibacterial substance against Aeromonas salmonesida. The inhibition constant (Ki) was 55 microM, which was as low as less than one tenth that of the Km value for the substrate, L-aspartate. In view of the fact that both aspartase and fumarase (J. Greenhut et al. (1985) J. Biol. Chem. 260, 6684-6686) were inhibited by DCAZ in competitive manners, common features of the reaction mechanism of the two enzymes were discussed. 相似文献
8.
K Higashi S Gotoh T Matsuhisa N Tateishi Y Sakamoto 《Biochimica et biophysica acta》1970,217(2):408-417
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Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss 下载免费PDF全文
Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
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Lends Alons Berbon Mélanie Habenstein Birgit Nishiyama Yusuke Loquet Antoine 《Journal of biomolecular NMR》2021,75(10-12):417-427
Journal of Biomolecular NMR - Solid-state NMR spectroscopy is a powerful technique to study insoluble and non-crystalline proteins and protein complexes at atomic resolution. The development of... 相似文献