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排序方式: 共有646条查询结果,搜索用时 9 毫秒
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Yoko Marutani Yasuo Yamauchi Mari Higashiyama Akihito Miyoshi Seiji Akimoto Kanako Inoue Ken-ichi Ikeda Masaharu Mizutani Yukihiro Sugimoto 《Photosynthesis research》2017,131(1):41-50
Light and temperature affect state transitions through changes in the plastoquinone (PQ) redox state in photosynthetic organisms. We demonstrated that light and/or heat treatment induced preferential photosystem (PS) I excitation by binding light-harvesting complex II (LHCII) proteins. The photosystem of wheat was in state 1 after dark overnight treatment, wherein PQ was oxidized and most of LHCII was not bound to PSI. At the onset of the light treatment [25 °C in the light (100 µmol photons m?2 s?1)], two major LHCIIs, Lhcb1 and Lhcb2 were phosphorylated, and the PSI–LHCII supercomplex formed within 5 min, which coincided with an increase in the PQ oxidation rate. Heat treatment at 40 °C of light-adapted wheat led to further LHCII protein phosphorylation of, resultant cyclic electron flow promotion, which was accompanied by ultrafast excitation of PSI and structural changes of thylakoid membranes, thereby protecting PSII from heat damage. These results suggest that LHCIIs are required for the functionality of wheat plant PSI, as it keeps PQ oxidized by regulating photochemical electron flow, thereby helping acclimation to environmental changes. 相似文献
3.
Hidetatsu Outani Minoru Okada Akihiro Yamashita Kanako Nakagawa Hideki Yoshikawa Noriyuki Tsumaki 《PloS one》2013,8(10)
The repair of large cartilage defects with hyaline cartilage continues to be a challenging clinical issue. We recently reported that the forced expression of two reprogramming factors (c-Myc and Klf4) and one chondrogenic factor (SOX9) can induce chondrogenic cells from mouse dermal fibroblast culture without going through a pluripotent state. We here generated induced chondrogenic (iChon) cells from human dermal fibroblast (HDF) culture with the same factors. We developed a chondrocyte-specific COL11A2 promoter/enhancer lentiviral reporter vector to select iChon cells. The human iChon cells expressed marker genes for chondrocytes but not fibroblasts, and were derived from non-chondrogenic COL11A2-negative cells. The human iChon cells formed cartilage but not tumors in nude mice. This approach could lead to the preparation of cartilage directly from skin in human, without going through pluripotent stem cells. 相似文献
4.
Kenichiro Kinouchi Atsuhiro Ichihara Motoaki Sano Ge-Hong Sun-Wada Yoh Wada Hiroki Ochi Toru Fukuda Kanako Bokuda Hideaki Kurosawa Naohiro Yoshida Shu Takeda Keiichi Fukuda Hiroshi Itoh 《PloS one》2013,8(11)
The ATPase 6 accessory protein 2 (ATP6AP2)/(pro)renin receptor (PRR) is essential for the biogenesis of active vacuolar H+-ATPase (V-ATPase). Genetic deletion of ATP6AP2/PRR causes V-ATPase dysfunction and compromises vesicular acidification. Here, we characterized the domains of ATP6AP2/PRR involved in active V-ATPase biogenesis. Three forms of ATP6AP2/PRR were found intracellularly: full-length protein and the N- and C-terminal fragments of furin cleavage products, with the N-terminal fragment secreted extracellularly. Genetic deletion of ATP6AP2/PRR did not affect the protein stability of V-ATPase subunits. The extracellular domain (ECD) and transmembrane domain (TM) of ATP6AP2/PRR were indispensable for the biogenesis of active V-ATPase. A deletion mutant of ATP6AP2/PRR, which lacks exon 4-encoded amino acids inside the ECD (Δ4M) and causes X-linked mental retardation Hedera type (MRXSH) and X-linked parkinsonism with spasticity (XPDS) in humans, was defective as a V-ATPase-associated protein. Prorenin had no effect on the biogenesis of active V-ATPase. The cleavage of ATP6AP2/PRR by furin seemed also dispensable for the biogenesis of active V-ATPase. We conclude that the N-terminal ECD of ATP6AP2/PRR, which is also involved in binding to prorenin or renin, is required for the biogenesis of active V-ATPase. The V-ATPase assembly occurs prior to its delivery to the trans-Golgi network and hence shedding of ATP6AP2/PRR would not affect the biogenesis of active V-ATPase. 相似文献
5.
Kumiko Ogawa Kyoko Nabae Jianqing Wang Kanako Wake So‐ichi Watanabe Mayumi Kawabe Osamu Fujiwara Satoru Takahashi Toshio Ichihara Seiko Tamano Tomoyuki Shirai 《Bioelectromagnetics》2009,30(3):205-212
The present study was designed to evaluate whether gestational exposure to an EMF targeting the head region, similar to that from cellular phones, might affect embryogenesis in rats. A 1.95‐GHz wide‐band code division multiple access (W‐CDMA) signal, which is one applied for the International Mobile Telecommunication 2000 (IMT‐2000) system and used for the freedom of mobile multimedia access (FOMA), was employed for exposure to the heads of four groups of pregnant CD(SD) IGS rats (20 per group) for gestational days 7–17. The exposure was performed for 90 min/day in the morning. The spatial average specific absorption rate (SAR) for individual brains was designed to be 0.67 and 2.0 W/kg with peak brain SARs of 3.1 and 7.0 W/kg for low (group 3) and high (group 4) exposures, respectively, and a whole‐body average SAR less than 0.4 W/kg so as not to cause thermal effects due to temperature elevation. Control and sham exposure groups were also included. At gestational day 20, all dams were killed and fetuses were taken out by cesarean section. There were no differences in maternal body weight gain. No adverse effects of EMF exposure were observed on any reproductive and embryotoxic parameters such as number of live (243–271 fetuses), dead or resorbed embryos, placental weights, sex ratios, weights or external, visceral or skeletal abnormalities of live fetuses. Bioelectromagnetics 30:205–212, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
6.
Kanako Hisata S. Fujiwara Yuko Tsuchida M. Ohashi Kazuo Kawamura 《Development genes and evolution》1998,208(10):537-546
Retinoic acid is thought to induce transdifferentiation of multipotent epithelial stem cells in the developing buds of the
ascidian Polyandrocarpa misakiensis. We isolated a cDNA clone from this species, named PmRAR, encoding a retinoic acid receptor (RAR) homologue. PmRAR clusters
with other RARs on phylogenetic trees constructed by three different methods. Within the cluster, PmRAR is on a separate branch
from all the subtypes of RARs, suggesting that RAR subtypes arose in the ancestral vertebrates after divergence of vertebrates
and urochordates. The embryos of another ascidian species Ciona intestinalis were co-electroporated with a mixture of a PmRAR expression vector and a lacZ reporter plasmid containing vertebrate-type retinoic acid response elements. The expression of lacZ depended on the presence of both retinoic acid and PmRAR, suggesting that PmRAR is a functional receptor. PmRAR mRNA is expressed
in the epidermis and mesenchyme cells of the Polyandrocarpa developing bud. The mRNA is not detectable in the mesenchyme cells in the adult body wall, but its expression can be induced
by retinoic acid in vitro. These results suggest that the PmRAR is a mediator of retinoic acid signalling in transdifferentiation
during asexual reproduction of protochordates.
Received: 6 April 1998 / Accepted: 27 July 1998 相似文献
7.
Dimethyl fumarate inhibits osteoclasts via attenuation of reactive oxygen species signalling by augmented antioxidation 下载免费PDF全文
8.
Hydrogen production by termite gut protists: characterization of iron hydrogenases of Parabasalian symbionts of the termite Coptotermes formosanus 下载免费PDF全文
Cellulolytic flagellated protists in the guts of termites produce molecular hydrogen (H(2)) that is emitted by the termites; however, little is known about the physiology and biochemistry of H(2) production from cellulose in the gut symbiotic protists due to their formidable unculturability. In order to understand the molecular basis for H(2) production, we here identified two genes encoding proteins homologous to iron-only hydrogenases (Fe hydrogenases) in Pseudotrichonympha grassii, a large cellulolytic symbiont in the phylum Parabasalia, in the gut of the termite Coptotermes formosanus. The two Fe hydrogenases were phylogenetically distinct and had different N-terminal accessory domains. The long-form protein represented a phylogenetic lineage unique among eukaryotic Fe hydrogenases, whereas the short form was monophyletic with those of other parabasalids. Active recombinant enzyme forms of these two Fe hydrogenases were successfully obtained without the specific auxiliary maturases. Although they differed in their extent of specific activity and optimal pH, both enzymes preferentially catalyzed H(2) evolution rather than H(2) uptake. H(2) evolution, at least that associated with the short-form enzyme, was still active even under high hydrogen partial pressure. H(2) evolution activity was detected in the hydrogenosomal fraction of P. grassii cells; however, the vigorous H(2) uptake activity of the endosymbiotic bacteria compensated for the strong H(2) evolution activity of the host protists. The results suggest that termite gut symbionts are a rich reservoir of novel Fe hydrogenases whose properties are adapted to the gut environment and that the potential of H(2) production in termite guts has been largely underestimated. 相似文献
9.
Kang SH Kim GR Seong M Baek SH Seol JH Bang OS Ovaa H Tatsumi K Komatsu M Tanaka K Chung CH 《The Journal of biological chemistry》2007,282(8):5256-5262
Ubiquitin-fold modifier 1 (Ufm1) is a recently identified new ubiquitin-like protein, whose tertiary structure displays a striking resemblance to ubiquitin. Similar to ubiquitin, it has a Gly residue conserved across species at the C-terminal region with extensions of various amino acid sequences that need to be processed in vivo prior to conjugation to target proteins. Here we report the isolation, cloning, and characterization of two novel mouse Ufm1-specific proteases, named UfSP1 and UfSP2. UfSP1 and UfSP2 are composed of 217 and 461 amino acids, respectively, and they have no sequence homology with previously known proteases. UfSP2 is present in most, if not all, of multicellular organisms including plant, nematode, fly, and mammal, whereas UfSP1 could not be found in plant and nematode upon data base search. UfSP1 and UfSP2 cleaved the C-terminal extension of Ufm1 but not that of ubiquitin or other ubiquitin-like proteins, such as SUMO-1 and ISG15. Both were also capable of releasing Ufm1 from Ufm1-conjugated cellular proteins. They were sensitive to inhibition by sulfhydryl-blocking agents, such as N-ethylmaleimide, and their active site Cys could be labeled with Ufm1-vinylmethylester. Moreover, replacement of the conserved Cys residue by Ser resulted in a complete loss of the UfSP1 and UfSP2 activities. These results indicate that UfSP1 and UfSP2 are novel thiol proteases that specifically process the C terminus of Ufm1. 相似文献
10.
Insecticide applications to soil contribute to the development of Burkholderia mediating insecticide resistance in stinkbugs 下载免费PDF全文
Kanako Tago Yoshitomo Kikuchi Sinji Nakaoka Chie Katsuyama Masahito Hayatsu 《Molecular ecology》2015,24(14):3766-3778
Some soil Burkholderia strains are capable of degrading the organophosphorus insecticide, fenitrothion, and establish symbiosis with stinkbugs, making the host insects fenitrothion‐resistant. However, the ecology of the symbiotic degrading Burkholderia adapting to fenitrothion in the free‐living environment is unknown. We hypothesized that fenitrothion applications affect the dynamics of fenitrothion‐degrading Burkholderia, thereby controlling the transmission of symbiotic degrading Burkholderia from the soil to stinkbugs. We investigated changes in the density and diversity of culturable Burkholderia (i.e. symbiotic and nonsymbiotic fenitrothion degraders and nondegraders) in fenitrothion‐treated soil using microcosms. During the incubation with five applications of pesticide, the density of the degraders increased from less than the detection limit to around 106/g of soil. The number of dominant species among the degraders declined with the increasing density of degraders; eventually, one species predominated. This process can be explained according to the competitive exclusion principle using Vmax and Km values for fenitrothion metabolism by the degraders. We performed a phylogenetic analysis of representative strains isolated from the microcosms and evaluated their ability to establish symbiosis with the stinkbug Riptortus pedestris. The strains that established symbiosis with R. pedestris were assigned to a cluster including symbionts commonly isolated from stinkbugs. The strains outside the cluster could not necessarily associate with the host. The degraders in the cluster predominated during the initial phase of degrader dynamics in the soil. Therefore, only a few applications of fenitrothion could allow symbiotic degraders to associate with their hosts and may cause the emergence of symbiont‐mediated insecticide resistance. 相似文献