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61.
Kensaku Maejima Masayoshi Hashimoto Yuka Hagiwara-Komoda Akio Miyazaki Masanobu Nishikawa Ryosuke Tokuda Kohei Kumita Noriko Maruyama Shigetou Namba Yasuyuki Yamaji 《Molecular Plant Pathology》2020,21(4):475-488
Plum pox virus (PPV) is one of the most important plant viruses causing serious economic losses. Thus far, strain typing based on the definition of 10 monophyletic strains with partially differentiable biological properties has been the sole approach used for epidemiological characterization of PPV. However, elucidating the genetic determinants underlying intra-strain biological variation among populations or isolates remains a relevant but unexamined aspect of the epidemiology of the virus. In this study, based on complete nucleotide sequence information of 210 Japanese and 47 non-Japanese isolates of the PPV-Dideron (D) strain, we identified five positively selected sites in the PPV-D genome. Among them, molecular studies showed that amino acid substitutions at position 2,635 in viral replicase correlate with viral titre and competitiveness at the systemic level, suggesting that amino acid position 2,635 is involved in aphid transmission efficiency and symptom severity. Estimation of ancestral genome sequences indicated that substitutions at amino acid position 2,635 were reversible and peculiar to one of two genetically distinct PPV-D populations in Japan. The reversible amino acid evolution probably contributes to the dissemination of the virus population. This study provides the first genomic insight into the evolutionary epidemiology of PPV based on intra-strain biological variation ascribed to positive selection. 相似文献
62.
Takumi Takata Seongmin Ha Tamaki Koide Noriko Fujii 《Protein science : a publication of the Protein Society》2020,29(4):941-951
Recent studies have suggested that the isomerization/racemization of aspartate residues in proteins increases in aged tissues. One such residue is Asp151 in lens‐specific αA‐crystallin. Although many isomerization/racemization sites have been reported in various proteins, the factors that lead to those modifications in proteins in vivo remain obscure. Therefore, an in vitro system is needed to assess the mechanisms of modifications of Asp under various conditions. Deamidation of Asn to Asp in proteins occurs more rapidly than isomerization/racemization of Asp, although the reaction passes through the same intermediate in both pathways. Here, therefore, we replaced Asp151 in human lens αA‐crystallin with Asn by using site‐directed mutagenesis. The recombinant protein was expressed in Escherichia coli and used to investigate the deamidation/isomerization/racemization of Asn151 after incubation at 50°C for various durations and under different pH. After incubation, the mutant αA‐crystallin was subjected to enzymatic digestion followed by liquid chromatography–MS/MS to evaluate the ratio of modifications in Asn151‐containing peptides. The Asp151Asn αA‐crystallin mutant showed rapid deamidation to Asp with the formation of specific Asp isomers. In particular, deamidation increased greatly under basic conditions. By contrast, subunit–subunit interactions between αA‐crystallin and αB‐crystallin had little effect on the modification of Asn151. Our findings suggest that the Asp151Asn αA‐crystallin mutant represents a good in vitro model protein to assess deamidation, isomerization, and the racemization intermediates. Furthermore, our in vitro results show a different trend from in vivo data, implying the presence of specific factors that induce racemization from L‐Asp to D‐Asp residues in vivo. 相似文献
63.
64.
Hiroaki Horikawa Midori Okada Yuko Nakamura Azusa Sato Noriko Iwamoto 《Free radical research》2013,47(10):1059-1065
The chemical properties of Amadori compounds in the presence of transition metal ions were studied, using the analogs 1-deoxy-1- n -butylamino- d -fructose (DBF) and N f -formyl-fructoselysine (fFL). The following characteristics were revealed: (a) DBF combined easily with Cu 2+ (but no other transition metal ions) to form a DBF-Cu 2+ complex in phosphate buffer, pH 7.4; (b) the complex was unstable, and degraded with the release of Cu + during incubation at 37°C; (c) degradation of the complex was associated with the production of hydroxyl radicals by the Fenton reaction and f -dicarbonyl compounds by non-autoxidative degradation; and (d) properties of DBF were similar to those of fFL. The above properties were additionally observed in glycated poly-Lys (GPL). Our findings indicate a novel mechanism for the generation of hydroxyl radicals and f -dicarbonyl compounds from Amadori adducts in the presence of Cu 2+ . 相似文献
65.
Noriko Umemoto Yuhei Nishimura Yasuhito Shimada Yukiko Yamanaka Seiya Kishi Saki Ito Kana Okamori Yuuki Nakamura Junya Kuroyanagi Zi Zhang Liqing Zang Zhipeng Wang Norihiro Nishimura Toshio Tanaka 《Molecular biotechnology》2013,55(2):131-142
A notable advantage of zebrafish as a model organism is the ease of gene knockdown using morpholino antisense oligonucleotide (MO). However, zebrafish morphants injected with MO for a target protein often show heterogeneous phenotypes, despite controlling the injection volume of the MO solution in all embryos. We developed a method for estimating the quantity of MO injected into each living morphant, based on the co-injection of a control MO labeled with the fluorophore lissamine. By applying this method for knockdown of cardiac troponin T (tnnt2a) in zebrafish, we could efficiently select the partial tnnt2a-depleted zebrafish with a decreased heart rate and impairment of cardiac contraction. To investigate cardiac impairment of the tnnt2a morphant, we performed fluorescent cardiac imaging using Bodipy-ceramide. Cardiac image analysis showed moderate reduction of tnnt2a impaired diastolic distensibility and decreased contraction and relaxation velocities. To the best of our knowledge, this is the first report to analyze the role of tnnt2a in cardiac function in tnnt2a-depleted living animals. Our combinatorial approach can be applied for analyzing the molecular function of any protein associated with human cardiac diseases. 相似文献
66.
Yusuke Shiromoto Satomi Kuramochi-Miyagawa Akito Daiba Shinichiro Chuma Ami Katanaya Akiko Katsumata Ken Nishimura Manami Ohtaka Mahito Nakanishi Toshinobu Nakamura Koichi Yoshinaga Noriko Asada Shota Nakamura Teruo Yasunaga Kanako Kojima-Kita Daisuke Itou Tohru Kimura Toru Nakano 《RNA (New York, N.Y.)》2013,19(6):803-810
piRNA (PIWI-interacting RNA) is a germ cell–specific small RNA in which biogenesis PIWI (P-element wimpy testis) family proteins play crucial roles. MILI (mouse Piwi-like), one of the three mouse PIWI family members, is indispensable for piRNA production, DNA methylation of retrotransposons presumably through the piRNA, and spermatogenesis. The biogenesis of piRNA has been divided into primary and secondary processing pathways; in both of these MILI is involved in mice. To analyze the molecular function of MILI in piRNA biogenesis, we utilized germline stem (GS) cells, which are derived from testicular stem cells and possess a spermatogonial phenotype. We established MILI-null GS cell lines and their revertant, MILI-rescued GS cells, by introducing the Mili gene with Sendai virus vector. Comparison of wild-type, MILI-null, and MILI-rescued GS cells revealed that GS cells were quite useful for analyzing the molecular mechanisms of piRNA production, especially the primary processing pathway. We found that glycerol-3-phosphate acyltransferase 2 (GPAT2), a mitochondrial outer membrane protein for lysophosphatidic acid, bound to MILI using the cells and that gene knockdown of GPAT2 brought about impaired piRNA production in GS cells. GPAT2 is not only one of the MILI bound proteins but also a protein essential for primary piRNA biogenesis. 相似文献
67.
Yoshitaka Kaitsu Kiminori Shimizu Eiji Tanaka Satoshi Shimano Shigeru Uchiyama Chihiro Tanaka Noriko Kinjo 《Mycological Progress》2013,12(4):755-761
Ophiocordyceps sessilis, a new species of Ophiocordycipitaceae, Hypocreales, was found on Camponotus obscuripes ants, where the ants were primarily infected by another close relative, O. pulvinata. Morphological observation clearly indicated that O. sessilis and O. pulvinata are distinct species. Ophiocordyceps sessilis exhibited superficial development of perithecia and ascospore disarticulation into part-spores, not known in O. pulvinata. Nucleotide sequence data suggested that O. sessilis belongs in Ophiocordyceps, Ophiocordycipitaceae. Molecular data also indicated that O. sessilis is a close relative of O. cuboidea, O. prolifica, O. paracuboidea, and O. ryogamiensis, which are all known to produce part-spores. Since O. sessilis is always associated with ants infected by O. pulvinata, O. sessilis may be a hyperparasite of O. pulvinata. 相似文献
68.
Hyunsoo Kim Taesoo Kim Byung-Chul Jeong Il-Taeg Cho Daehee Han Noriko Takegahara Takako Negishi-Koga Hiroshi Takayanagi Jae Hee Lee Jai-Yoon Sul Vikram Prasad Seoung Hoon Lee Yongwon Choi 《Cell metabolism》2013,17(2):249-260
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69.
Takashi Nobusawa Yoko Okushima Noriko Nagata Mikiko Kojima Hitoshi Sakakibara Masaaki Umeda 《PLoS biology》2013,11(4)
Plant organ growth is controlled by inter-cell-layer communication, which thus determines the overall size of the organism. The epidermal layer interfaces with the environment and participates in both driving and restricting growth via inter-cell-layer communication. However, it remains unknown whether the epidermis can send signals to internal tissue to limit cell proliferation in determinate growth. Very-long-chain fatty acids (VLCFAs) are synthesized in the epidermis and used in the formation of cuticular wax. Here we found that VLCFA synthesis in the epidermis is essential for proper development of Arabidopsis thaliana. Wild-type plants treated with a VLCFA synthesis inhibitor and pasticcino mutants with defects in VLCFA synthesis exhibited overproliferation of cells in the vasculature or in the rib zone of shoot apices. The decrease of VLCFA content increased the expression of IPT3, a key determinant of cytokinin biosynthesis in the vasculature, and, indeed, elevated cytokinin levels. These phenotypes were suppressed in ipt3;5;7 triple mutants, and also by vasculature-specific expression of cytokinin oxidase, which degrades active forms of cytokinin. Our results imply that VLCFA synthesis in the epidermis is required to suppress cytokinin biosynthesis in the vasculature, thus fine-tuning cell division activity in internal tissue, and therefore that shoot growth is controlled by the interaction between the surface (epidermis) and the axis (vasculature) of the plant body. 相似文献
70.
Gaku Takibuchi Hirotake Imanishi Mami Morimoto Kaori Ishikawa Kazuto Nakada Noriko Toyama-Sorimachi Yoshiaki Kikkawa Keizo Takenaga Jun-Ichi Hayashi 《Mitochondrion》2013,13(6):881-887
To examine whether polymorphic mtDNA mutations that do not induce significant respiration defects regulate phenotypes of tumor cells, we used mouse transmitochondrial tumor cells (cybrids) with nuclear DNA from C57BL/6 (B6) strain and mtDNA from allogenic C3H strain. The results showed that polymorphic mutations of C3H mtDNA in the cybrids induced hypoxia sensitivity, resulting in a delay of tumor formation on their subcutaneous inoculation into B6 mice. Therefore, the effects of polymorphic mutations in normal mtDNA have to be carefully considered, particularly when we apply the gene therapy to the embryos to replace their pathogenic mtDNA by normal mtDNA. 相似文献