Utsunomiya University

About: Utsunomiya University is a education organization based out in Utsunomiya, Japan. It is known for research contribution in the topics: Laser & Holography. The organization has 4139 authors who have published 6812 publications receiving 91975 citations. The organization is also known as: Utsunomiya daigaku.

PVYNTN‐NW, a novel recombinant strain of Potato virus Y predominating in potato fields in Syria

Abstract: Detailed characterization of a number of isolates of PVYSYR, a novel recombinant strain of Potato virus Y (PVY) from Syria, was conducted to elucidate their origin, assess their significance and achieve a final classification of PVYSYR. Recombination analysis grouped isolates of PVYSYR into three recombination patterns, SYR-I, SYR-II and SYR-III, which varied in the first 700 nucleotides of their genomes, with the second recombination pattern, SYR-II, the most frequent. PVYSYR isolates shared highest genomic identity and close phylogenetic relationships with PVYNTN and PVYNW isolates from Syria, suggesting a common origin and local emergence of these isolates in Syria. All PVYSYR isolates (total of 20) induced tobacco veinal necrosis, but reacted to a PVYO monoclonal antibody, typical characteristics of the previously reported PVYNW (or PVYN:O). In potato, however, four isolates tested (one of SYR-I and three of SYR-II) induced potato tuber necrotic ringspot disease (PTNRD), which is the characteristic phenotype of PVYNTN. Given the shared properties of SYR-I and SYR-II isolates with PVYNTN and PVYNW, it was decided that they represent a new recombinant strain of the PVYN strain group, with the proposed name PVYNTN-NW. The classification of SYR-III will be possible only after testing the phenotype in potato. The high prevalence of PVYNTN-NW in potatoes and weeds, as well as its ability to induce PTNRD, demonstrates its importance and the necessity for its control.

The assembly and maintenance of heterochromatin initiated by transgene repeats are independent of the RNA interference pathway in mammalian cells.

Abstract: A role for the RNA interference (RNAi) pathway in the establishment of heterochromatin is now well accepted for various organisms. Less is known about its relevance and precise role in mammalian cells. We previously showed that tandem insertion of a 1,000-copy inducible transgene into the genome of baby hamster kidney (BHK) cells initiated the formation of an extremely condensed chromatin locus. Here, we characterized the inactive transgenic locus as heterochromatin, since it was associated with heterochromatin protein 1 (HP1), histone H3 trimethylated at lysine 9, and cytosine methylation in CpG dinucleotides. Northern blot analysis did not detect any transgene-derived small RNAs. RNAi-mediated Dicer knockdown did not disrupt the heterochromatic transgenic locus or up-regulate transgene expression. Moreover, neither Dicer knockdown nor overexpression of transgene-directed small interfering RNAs altered the bidirectional transition of the transgenic locus between the heterochromatic and euchromatic states. Interestingly, tethering of HP1 to the transgenic locus effectively induced transgene silencing and chromatin condensation in a Dicer-independent manner, suggesting a role for HP1 in maintaining the heterochromatic locus. Our results suggest that the RNAi pathway is not required for the assembly and maintenance of noncentromeric heterochromatin initiated by tandem transgene repeats in mammalian cells.

Elastic properties of semiconductors studied by extended Hückel theory

Abstract: For thirty diamond- and zinc-blende-structure semiconductors, the elastic shear constant (${\mathit{c}}_{11}$-${\mathit{c}}_{12}$)/2, polarity ${\mathrm{\ensuremath{\alpha}}}_{\mathit{p}}$, effective atomic charge ${\mathit{Z}}^{\mathrm{*}}$, transfer parameter \ensuremath{\beta}, and transverse charge ${\mathit{e}}_{\mathrm{T}}^{\mathrm{*}}$ are calculated from band-structure calculations based on the extended H\"uckel tight-binding method. The results are compared with previous theoretical calculations and experiment. It is found that improved agreement with experiment is obtained for (${\mathit{c}}_{11}$-${\mathit{c}}_{12}$)/2 in comparison to a calculation based upon universal tight-binding parameters, which was already in rather good accord. For the effective charges, inclusion of nonorthogonalities in the H\"uckel theory increases their estimated values considerably and brings them into good agreement with experiment.

Cadmium accumulation in the shoots and roots of 93 weed species

Abstract: The present study was conducted to find useful weed species for cadmium (Cd) phytoremediation. Ninety-three weed species and eight crop species were grown for 2 months in pots containing sandy loam soil with 3 mg Cd kg−1 dry weight (DW). The Cd concentrations in the shoots and roots of all species were determined by inductively coupled plasma optical emission spectroscopy and atomic absorption spectrometry. Shoot Cd concentrations (mg kg−1 DW) of Cichorium intybus (77.0) and Matricaria chamomilla (64.4) were higher than that of Polygonum thunbergii (56.2), which is a recognized hyperaccumulator. Root Cd concentrations (mg kg−1 DW) were relatively high (≥ 100) in 11 species, for example, Oenothera biennis (171.9), Calystegia sepium var. americana (122.6) and Cassia obtusifolia (122.2). Shoot–root ratios (ratio of shoot and root Cd concentrations) were higher in Compositae species, for example, Cichorium intybus (3.56) and Bidens frondosa (3.30), than in Gramineae species, for example, Oenothera bi...