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991.
992.
Miyuki T. Nakata Mao Nakao Asuka Denda Yusuke Onoda Haruko Ueda Taku Demura 《Plant Biotechnology》2020,37(4):471
The mechanical strength of a plant stem (a load-bearing organ) helps the plant resist drooping, buckling and fracturing. We previously proposed a method for quickly evaluating the stiffness of an inflorescence stem in the model plant Arabidopsis thaliana based on measuring its natural frequency in a free-vibration test. However, the relationship between the stiffness and flexural rigidity of inflorescence stems was unclear. Here, we compared our previously described free-vibration test with the three-point bending test, the most popular method for calculating the flexural rigidity of A. thaliana stems, and examined the extent to which the results were correlated. Finally, to expand the application range, we present an example of a modified free-vibration test. Our results provide a reference for improving estimates of the flexural rigidity of A. thaliana inflorescence stems. 相似文献
993.
Shinnosuke Takagi Yohei Iguchi Masahisa Katsuno Shinsuke Ishigaki Kensuke Ikenaka Yusuke Fujioka Daiyu Honda Jun-ichi Niwa Fumiaki Tanaka Hirohisa Watanabe Hiroaki Adachi Gen Sobue 《PloS one》2013,8(6)
Phosphorylated and truncated TAR DNA-binding protein-43 (TDP-43) is a major component of ubiquitinated cytoplasmic inclusions in neuronal and glial cells of two TDP-43 proteinopathies, amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Modifications of TDP-43 are thus considered to play an important role in the pathogenesis of TDP-43 proteinopathies. However, both the initial cause of these abnormal modifications and the TDP-43 region responsible for its aggregation remain uncertain. Here we report that the 32 kDa C-terminal fragment of TDP-43, which lacks the RNP2 motif of RNA binding motif 1 (RRM1), formed aggregates in cultured cells, and that similar phenotypes were obtained when the RNP2 motif was either deleted from or mutated in full-length TDP-43. These aggregations were ubiquitinated, phosphorylated and truncated, and sequestered the 25 kDa C-terminal TDP-43 fragment seen in the neurons of TDP-43 proteinopathy patients. In addition, incubation with RNase decreased the solubility of TDP-43 in cell lysates. These findings suggest that the RNP2 motif of RRM1 plays a substantial role in pathological TDP-43 modifications and that it is possible that disruption of RNA binding may underlie the process of TDP-43 aggregation. 相似文献
994.
Toshihiro Murata Erdenechimeg Selenge Kento Suganuma Yusuke Asai Javzan Batkhuu Fumihiko Yoshizaki 《Phytochemistry letters》2013,6(4):552-555
Two new chromone acyl glucosides, 5-hydroxy-7-O-(6-O-p-cis-coumaroyl-β-D-glucopyranosyl)-chromone (1) and 5-hydroxy-7-O-(6-O-p-trans-coumaroyl-β-D-glucopyranosyl)-chromone (2), and a new flavonoid glucoside, ayanin 3′-O-β-D-glucopyranoside (3) were isolated from aerial parts of Dasiphora parvifolia, together with flavonoid glycosides (4–10), catechins (11, 12), and hydrolysable tannins (13, 14). The chemical structures of these compounds were elucidated on the basis of spectroscopic data. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and the hyaluronidase inhibitory activity of these compounds were evaluated. 相似文献
995.
Liqiu Ma Yusuke Kazama Hirokazu Inoue Tomoko Abe Shin Hatakeyama Shuuitsu Tanaka 《Fungal biology》2013,117(4):227-238
Heavy-ion beams are known to cause great damage to cellular components and are particularly renowned for their ability to generate DNA double-strand breaks (DSBs). To gain insight into the mutagenic effect of carbon-ion beams and how such damage is repaired by the cell, Neurospora crassa mutants deficient in one of three components involved in the repair of DSBs, nonhomologous end-joining (NHEJ), homologous recombination repair (HR), and the Mre11-Rad50-Xrs2 (MRX) complex, were irradiated with a carbon-ion beam and killing effect, mutation frequencies, and the type of mutation incurred by survivors were analysed. The sensitivity of the NHEJ-deficient strain (mus-52) was higher than that of the wild-type and the HR-deficient (mei-3) strains at low doses of radiation, but was little changed as the level increased. As a result both the wild-type and HR-deficient strains were more sensitive than the NHEJ-deficient strain at high radiation levels. In addition, the frequency of forward mutation at the adenine-3 (ad-3) loci of the NHEJ-deficient mutant was lower than that of the wild-type strain at all levels, while the mutation frequency of the HR-deficient strain was consistently ∼3-fold higher than the wild-type. From the comparison of mutation type of each strain, deletions were frequently observed in wild-type strain, whilst base substitution and deletion in the mus-52 and mei-3 strains. These mutations resulting from carbon-ion-beam irradiation depend on the mechanism invoked to cope with DSBs. Furthermore, in wild-type cells, these mechanisms likely compete to repair DSBs. 相似文献
996.
Jiro Harada Tadashi Mizoguchi Souichirou Satoh Yusuke Tsukatani Makio Yokono Masato Noguchi Ayumi Tanaka Hitoshi Tamiaki 《PloS one》2013,8(4)
The gene named bciD, which encodes the enzyme involved in C7-formylation in bacteriochlorophyll e biosynthesis, was found and investigated by insertional inactivation in the brown-colored green sulfur bacterium Chlorobaculum limnaeum (previously called Chlorobium phaeobacteroides). The bciD mutant cells were green in color, and accumulated bacteriochlorophyll c homologs bearing the 7-methyl group, compared to C7-formylated BChl e homologs in the wild type. BChl-c homolog compositions in the mutant were further different from those in Chlorobaculum tepidum which originally produced BChl c: (31
S)-8-isobutyl-12-ethyl-BChl c was unusually predominant. 相似文献
997.
Makoto Tokuda Yusuke Jikumaru Keiichiro Matsukura Yumiko Takebayashi Shun Kumashiro Masaya Matsumura Yuji Kamiya 《PloS one》2013,8(4)
The maize orange leafhopper Cicadulina bipunctata (Hemiptera: Cicadellidae) induces galls characterized by growth stunting and severe swelling of leaf veins on various plants of Poaceae. Previous studies revealed that galls are induced not on feeding site but on distant, newly extended leaves during the feeding, and strongly suggested that some chemicals injected by the leafhopper affect at the leaf primordia. To approach the mechanism underlying gall induction by C. bipunctata, we examined physiological response of plants to feeding by the leafhopper. We performed high-throughput and comprehensive plant hormone analyses using LC-ESI-MS/MS. Galled maize leaves contained higher contents of abscisic acid (ABA) and trans-Zeatin (tZ) and lower contents of gibberellins (GA1 and GA4) than ungalled maize leaves. Leafhopper treatment significantly increased ABA and tZ contents and decreased GA1 and GA4 contents in extending leaves. After the removal of leafhoppers, contents of tZ and gibberellins in extending leaves soon became similar to the control values. ABA content was gradually decreased after the removal of leafhoppers. Such hormonal changes were not observed in leafhopper treatment on leaves of resistant maize variety. Water contents of galled leaves were significantly lower than control leaves, suggesting water stress of galled leaves and possible reason of the increase in ABA content. These results imply that ABA, tZ, and gibberellins are related to gall induction by the leafhopper on susceptible variety of maize. 相似文献
998.
Keiko Miwa Jong-Kook Lee Yoshiko Takagishi Tobias Opthof Xianming Fu Masumi Hirabayashi Kazuhiko Watabe Yasuhiko Jimbo Itsuo Kodama Issei Komuro 《PloS one》2013,8(7)
Molecular signaling of cardiac autonomic innervation is an unresolved issue. Here, we show that glial cell line-derived neurotrophic factor (GDNF) promotes cardiac sympathetic innervation in vitro and in vivo. In vitro, ventricular myocytes (VMs) and sympathetic neurons (SNs) isolated from neonatal rat ventricles and superior cervical ganglia were cultured at a close distance. Then, morphological and functional coupling between SNs and VMs was assessed in response to GDNF (10 ng/ml) or nerve growth factor (50 ng/ml). As a result, fractions of neurofilament-M-positive axons and synapsin-I-positive area over the surface of VMs were markedly increased with GDNF by 9-fold and 25-fold, respectively, compared to control without neurotrophic factors. Pre- and post-synaptic stimulation of β1-adrenergic receptors (BAR) with nicotine and noradrenaline, respectively, resulted in an increase of the spontaneous beating rate of VMs co-cultured with SNs in the presence of GDNF. GDNF overexpressing VMs by adenovirus vector (AdGDNF-VMs) attracted more axons from SNs compared with mock-transfected VMs. In vivo, axon outgrowth toward the denervated myocardium in adult rat hearts after cryoinjury was also enhanced significantly by adenovirus-mediated GDNF overexpression. GDNF acts as a potent chemoattractant for sympathetic innervation of ventricular myocytes, and is a promising molecular target for regulation of cardiac function in diseased hearts. 相似文献
999.
1000.