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281.
Lupas Andrei Zühl Frank Tamura Tomohiro Wolf Stefan Nagy István De Mot René Baumeister Wolfgang 《Molecular biology reports》1997,24(1-2):125-131
Proteasomes are large, multisubunit proteases with highly conserved structures. The 26S proteasome of eukaryotes is an ATP-dependent enzyme of about 2 MDa, which acts as the central protease of the ubiquitin-dependent pathway of protein degradation. The core of the 26S complex is formed by the 20S proteasome, an ATP-independent, barrel-shaped protease of about 700 kDa, which has also been detected in archaebacteria and, more recently, in eubacteria. Currently, the distribution of 20S proteasomes in eubacteria appears limited to the actinomycetes, while most other eubacteria contain a related complex of simpler structure. 相似文献
282.
Makoto M. Watanabe Yoshie Takeda Tsutomu Sasa Isao Inouye Shoichiro Suda Tomohiro Sawaguchi Mitsuo Chihara 《Journal of phycology》1987,23(Z2):382-389
A green-colored marine unicell has been grown in unialgal culture and its morphology, chloroplast fine structure, and chlorophyll composition investigated. The organism is typical of dinoflagellates in its shape, flagellation, nucleus, mitochondria, and trichocysts. It is similar to Gymnodinium but possesses fine body scales. Chloroplasts and two kinds of vesicles bounded by double membranes, but no organelles obviously identifiable as nuclei or mitochondria, are associated in ribosome-dense cytoplasm separated by a double membrane from the dinophycean cytoplasm. The chloroplasts are unlike any previously reported for dinoflagellates. Each is enclosed by an envelope consisting of a double membrane. Chloroplast lamellae consist of three appressed thylakoids. Interlamellar pyrenoids are present. Pigment analysis reveals chlorophylls a and b but not chlorophyll c. It seems likely that the organism is an undescribed dinoflagellate containing an endosymbiont with chlorophylls a and b and that the reduction of the endosymbiont nucleus and mitochondria has permitted a more initmate symbiosis. 相似文献
283.
284.
J Timothy Lightfoot Michael J Turner Amy Kleinfehn Knab Anne E Jedlicka Tomohiro Oshimura Jacqui Marzec Wesley Gladwell Larry J Leamy Steven R Kleeberger 《Journal of applied physiology》2007,103(1):105-110
The role of genetics in the determination of maximal exercise endurance is unclear. Six- to nine-week-old F2 mice (n = 99; 60 female, 39 male), derived from an intercross of two inbred strains that had previously been phenotyped as having high maximal exercise endurance (Balb/cJ) and low maximal exercise endurance (DBA/2J), were treadmill tested to estimate exercise endurance. Selective genotyping of the F2 cohort (n = 12 high exercise endurance; n = 12 low exercise endurance) identified a significant quantitative trait locus (QTL) on chromosome X (53.7 cM, DXMit121) in the entire cohort and a suggestive QTL on chromosome 8 (36.1 cM, D8Mit359) in the female mice. Fine mapping with the entire F2 cohort and additional informative markers confirmed and narrowed the QTLs. The chromosome 8 QTL (EE8(F)) is homologous with two suggestive human QTLs and one significant rat QTL previously linked with exercise endurance. No effect of sex (P = 0.33) or body weight (P = 0.79) on exercise endurance was found in the F2 cohort. These data indicate that genetic factors in distinct chromosomal regions may affect maximal exercise endurance in the inbred mouse. Whereas multiple genes are located in the identified QTL that could functionally affect exercise endurance, this study serves as a foundation for further investigations delineating the identity of genetic factors influencing maximum exercise endurance. 相似文献
285.
Tomohiro Ueda Tomohisa Takagi Kazuhiro Katada Takaya Iida Katsura Mizushima Osamu Dohi Tetsuya Okayama Naohisa Yoshida Kazuhiro Kamada Kazuhiko Uchiyama Osamu Handa Takeshi Ishikawa Hideyuki Konishi Yuji Naito Yukio Nagasaki Yoshito Itoh 《Biochemical and biophysical research communications》2018,495(2):2044-2049
Background
Intestinal ischemia-reperfusion (I-R) injury is a serious abdominal condition leading to multiple organ failure with high mortality. However, no reliable treatment is available. A redox nanoparticle (RNPO) was recently developed, and its efficacy for several intestinal inflammatory conditions has been reported. To this end, the aim of this study was to investigate the therapeutic effects of RNPO on intestinal I-R injury in mice.Methods
Ischemia was induced in the small intestine of C57BL/6 mice by occluding the superior mesenteric artery for 45 min under anesthesia followed by reperfusion for 4 h. Mice were orally administered the vehicle or RNPO 1 h before ischemia. Inflammatory markers such as histological findings, thiobarbituric acid (TBA)-reactive substances as an index of lipid peroxidation, myeloperoxidase (MPO) activity as an index of neutrophil infiltration, and expression of pro-inflammatory cytokine mRNA in the intestinal mucosa were assessed.Results
Induction of I-R caused a significant increase in inflammatory markers (histological scores, TBA-reactive substances, MPO activity, and expression of keratinocyte chemoattractant mRNA). These changes were significantly attenuated in RNPO-treated mice as compared to vehicle-treated mice.Conclusion
Orally administered RNPO attenuated intestinal I-R injury in mice in association with reductions in neutrophil infiltration and lipid peroxidation, suggesting the possibly potential of RNPO as a therapeutic agent for intestinal I-R injury. 相似文献286.
Botulinum hemagglutinin‐mediated in situ break‐up of human induced pluripotent stem cell aggregates for high‐density suspension culture 下载免费PDF全文
Suman C. Nath Tomohiro Tokura Mee‐Hae Kim Masahiro Kino‐oka 《Biotechnology and bioengineering》2018,115(4):910-920
Large numbers of human induced pluripotent stem cells (hiPSCs) are required for making stable cell bank. Although suspension culture yields high cell numbers, there remain unresolved challenges for obtaining high‐density of hiPSCs because large size aggregates exhibit low growth rates. Here, we established a simple method for hiPSC aggregate break‐up using botulinum hemagglutinin (HA), which specifically bound with E‐cadherin and disrupted cell–cell connections in hiPSC aggregates. HA showed temporary activity for disrupting the E‐cadherin‐mediated cell–cell connections to facilitate the break‐up of aggregates into small sizes only 9 hr after HA addition. The transportation of HA into the aggregates was mediated by transcellular and paracellular way after HA addition to the culture medium. hiPSC aggregates broken up by HA showed a higher number of live cells, higher cell density, and higher expansion fold compared to those of aggregates dissociated with enzymatic digestion. Moreover, a maximum cell density of 4.5 ± 0.2 × 106 cells ml?1 was obtained by aggregate break‐up into small ones, which was three times higher than that with the conventional culture without aggregate break‐up. Therefore, the temporary activity of HA for disrupting E‐cadherin‐mediated cell–cell connection was key to establishing a simple in situ method for hiPSC aggregate break‐up in bioreactors, leading to high cell density in suspension culture. 相似文献
287.
Yuji Miyazaki Yusuke Jikumaru Tomoyuki Takase Aya Saitoh Asuka Sugitani Yuji Kamiya Tomohiro Kiyosue 《Plant cell reports》2016,35(2):455-467
Key message
Auxin and two phytochrome-interacting factors, PHYTOCHROME-INTERACTING FACTOR4 (PIF4) and PIF5, play crucial roles in the enhancement of hypocotyl elongation in transgenic Arabidopsis thaliana plants that overproduce LOV KELCH PROTEIN2 (LKP2).Abstract
LOV KELCH PROTEIN2 (LKP2) is a positive regulator of hypocotyl elongation under white light in Arabidopsis thaliana. In this study, using microarray analysis, we compared the gene expression profiles of hypocotyls of wild-type Arabidopsis (Columbia accession), a transgenic line that produces green fluorescent protein (GFP), and two lines that produce GFP-tagged LKP2 (GFP-LKP2). We found that, in GFP-LKP2 hypocotyls, 775 genes were up-regulated, including 36 auxin-responsive genes, such as 27 SMALL AUXIN UP RNA (SAUR) and 6 AUXIN/INDOLE-3-ACETIC ACID (AUX/IAA) genes, and 21 genes involved in responses to red or far-red light, including PHYTOCHROME-INTERACTING FACTOR4 (PIF4) and PIF5; and 725 genes were down-regulated, including 15 flavonoid biosynthesis genes. Hypocotyls of GFP-LKP2 seedlings, but not cotyledons or roots, contained a higher level of indole-3-acetic acid (IAA) than those of control seedlings. Auxin inhibitors reduced the enhancement of hypocotyl elongation in GFP-LKP2 seedlings by inhibiting the increase in cortical cell number and elongation of the epidermal and cortical cells. The enhancement of hypocotyl elongation was completely suppressed in progeny of the crosses between GFP-LKP2 lines and dominant gain-of-function auxin-resistant mutants (axr2-1 and axr3-1) or loss-of-function mutants pif4, pif5, and pif4 pif5. Our results suggest that the enhancement of hypocotyl elongation in GFP-LKP2 seedlings is due to the elevated level of IAA and to the up-regulated expression of PIF4 and PIF5 in hypocotyls.288.
Use of Candida‐specific chicken egg yolk antibodies to inhibit the adhering of Candida to denture base materials: prevention of denture stomatitis 下载免费PDF全文
289.
Toshio Sekiguchi Kenji Kuwasako Michio Ogasawara Hiroki Takahashi Shin Matsubara Tomohiro Osugi Ikunobu Muramatsu Yuichi Sasayama Nobuo Suzuki Honoo Satake 《The Journal of biological chemistry》2016,291(5):2345-2356
The calcitonin (CT)/CT gene-related peptide (CGRP) family is conserved in vertebrates. The activities of this peptide family are regulated by a combination of two receptors, namely the calcitonin receptor (CTR) and the CTR-like receptor (CLR), and three receptor activity-modifying proteins (RAMPs). Furthermore, RAMPs act as escort proteins by translocating CLR to the cell membrane. Recently, CT/CGRP family peptides have been identified or inferred in several invertebrates. However, the molecular characteristics and relevant functions of the CTR/CLR and RAMPs in invertebrates remain unclear. In this study, we identified three CT/CGRP family peptides (Bf-CTFPs), one CTR/CLR-like receptor (Bf-CTFP-R), and three RAMP-like proteins (Bf-RAMP-LPs) in the basal chordate amphioxus (Branchiostoma floridae). The Bf-CTFPs were shown to possess an N-terminal circular region typical of the CT/CGRP family and a C-terminal Pro-NH2. The Bf-CTFP genes were expressed in the central nervous system and in endocrine cells of the midgut, indicating that Bf-CTFPs serve as brain and/or gut peptides. Cell surface expression of the Bf-CTFP-R was enhanced by co-expression with each Bf-RAMP-LP. Furthermore, Bf-CTFPs activated Bf-CTFP-R·Bf-RAMP-LP complexes, resulting in cAMP accumulation. These results confirmed that Bf-RAMP-LPs, like vertebrate RAMPs, are prerequisites for the function and translocation of the Bf-CTFP-R. The relative potencies of the three peptides at each receptor were similar. Bf-CTFP2 was a potent ligand at all receptors in cAMP assays. Bf-RAMP-LP effects on ligand potency order were distinct to vertebrate CGRP/adrenomedullin/amylin receptors. To the best of our knowledge, this is the first molecular and functional characterization of an authentic invertebrate CT/CGRP family receptor and RAMPs. 相似文献
290.