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131.
132.
Background
To induce potent epitope-specific T cell immunity by a peptide-based vaccine, epitope peptides must be delivered efficiently to antigen-presenting cells (APCs) in vivo. Therefore, selecting an appropriate peptide carrier is crucial for the development of an effective peptide vaccine. In this study, we explored new peptide carriers which show enhancement in cytotoxic T lymphocyte (CTL) induction capability.Methodology/Principal Findings
Data from an epitope-specific in vivo CTL assay revealed that phosphatidylserine (PS) has a potent adjuvant effect among candidate materials tested. Further analyses showed that PS-conjugated antigens were preferentially and efficiently captured by professional APCs, in particular, by CD11c+CD11b+MHCII+ conventional dendritic cells (cDCs) compared to multilamellar liposome-conjugates or unconjugated antigens. In addition, PS demonstrated the stimulatory capacity of peptide-specific helper T cells in vivo.Conclusions/Significance
This work indicates that PS is the easily preparable efficient carrier with a simple structure that delivers antigen to professional APCs effectively and induce both helper and cytotoxic T cell responses in vivo. Therefore, PS is a promising novel adjuvant for T cell-inducing peptide vaccines. 相似文献133.
Kentaro Kumoi Tadashi Satoh Kazuyoshi Murata Takeshi Hiromoto Tsunehiro Mizushima Yukiko Kamiya Masanori Noda Susumu Uchiyama Hirokazu Yagi Koichi Kato 《PloS one》2013,8(3)
Assembly of the eukaryotic 20S proteasome is an ordered process involving several proteins operating as proteasome assembly factors including PAC1-PAC2 but archaeal 20S proteasome subunits can spontaneously assemble into an active cylindrical architecture. Recent bioinformatic analysis identified archaeal PAC1-PAC2 homologs PbaA and PbaB. However, it remains unclear whether such assembly factor-like proteins play an indispensable role in orchestration of proteasome subunits in archaea. We revealed that PbaB forms a homotetramer and exerts a dual function as an ATP-independent proteasome activator and a molecular chaperone through its tentacle-like C-terminal segments. Our findings provide insights into molecular evolution relationships between proteasome activators and assembly factors. 相似文献
134.
Sea skaters, genus Halobates Eschscholtz, 1822, are the only marine insects living in mangrove beds and the tide pools of coral reefs, both of which provide dramatically variable habitats daily by virtue of tide-driven changes in surface level. Females of H. japonicus Esaki, 1924 were collected from three distinct aggregations in a single bay (24°27′5″N, 124°8′40″E) on 1–5 November 2006. Two aggregations were formed in respective tide pools of the coral reef and one was formed in the mangrove beds. Amplified fragment length polymorphism markers were used to detect the persistency of each aggregation at a mesoscale. The results suggested that H. japonicus repeatedly immigrated from outside the bay to establish a meta-population of several deme groups. Aggregations along the coastline had some persistency to the line itself and had little tendency to cross to the opposite shore, even when the distance was short. 相似文献
135.
136.
Junichi Satoh Hiroyuki Koshino Kouta Sekino Shinsaku Ito Ryo Katsuta Kouji Takeda 《Bioscience, biotechnology, and biochemistry》2016,80(2):363-367
A new compound in cucumber, Cucumis sativus, nutrient solution that appears under iron-deficient conditions, but not under ordinary culture conditions, has been revealed by HPLC analysis. The chemical structure of this compound was identified using LC-MS and NMR techniques as that of 4′-ketoriboflavin. This is the first report to show that 4′-ketoriboflavin can be found in metabolites from organisms. 相似文献
137.
Xiaona Wang Saki Fujita Tatsuro Nakaji Makoto Watanabe Fuyuki Satoh Takayoshi Koike 《Trees - Structure and Function》2016,30(2):363-374
Key message
Elevated CO 2 reduced fine root dynamics (production and turnover) of white birch seedlings, especially grown in volcanic ash soil compared with brown forest soil.Abstract
Increased atmospheric CO2 usually enhances photosynthetic ability and growth of trees. To understand how increased CO2 affects below-ground part of trees under varied soil condition, we investigated the responses of the fine root (diameter <2 mm) dynamics of Japanese white birch (Betula platyphylla var. japonica) which was planted in 2010. The three-year-old birch seedlings were grown in four experimental treatments comprising two levels of CO2, i.e., ambient: 380–390 and elevated: 500 μmol mol?1, in combination with two kinds of soil: brown forest (BF) soil and volcanic ash (VA) soil which has few nutrients. The growth and turnover of fine roots were measured for 3 years (2011–2013) using the Mini-rhizotron. In the first observation year, live fine root length (standing crop) in BF soil was not affected by CO2 treatment, but it was reduced by the elevated CO2 from the second observation year. In VA soil, live fine root length was reduced by elevated CO2 for all 3 years. Fine root turnover tended to decrease under elevated CO2 compared with ambient in both soil types during the first and second observation years. Turnover of fine root production and mortality was also affected by the two factors, elevated CO2 and different soil types. Median longevity of fine root increased under elevated CO2, especially in VA soil at the beginning, and a shorter fine root lifespan appeared after 2 years of observation (2011–2012). These results suggest that elevated CO2 does not consistently stimulate fine root turnover, particularly during the plant seedlings stage, as it may depend on the costs and benefits of constructing and retaining roots. Therefore, despite the other uncontrollable environment factors, carbon sequestration to the root system may be varied by CO2 treatment period, soil type and plant age.138.
Matsui S Satoh H Kawashima H Nagasaka S Niu CF Urushida T Katoh H Watanabe Y Hayashi H 《Canadian journal of physiology and pharmacology》2007,85(2):264-273
Aldosterone has non-genomic effects that express within minutes and modulate intracellular ion milieu and cellular function. However, it is still undefined whether aldosterone actually alters intracellular ion concentrations or cellular contractility. To clarify the non-genomic effects of aldosterone, we measured [Na+]i, Ca2+ transient (CaT), and cell volume in dye-loaded rat ventricular myocytes, and we also evaluated myocardial contractility. We found the following: (i) aldosterone increased [Na+]i at the concentrations of 100 nmol/L to 10 micromol/L; (ii) aldosterone (up to 10 micromol/L) did not alter CaT and cell shortening in isolated myocytes, developed tension in papillary muscles, or left ventricular developed pressure in Langendorff-perfused hearts; (iii) aldosterone (100 nmol/L) increased the cell volume from 47.5 +/- 3.6 pL to 49.8 +/- 3.7 pL (n=8, p<0.05); (iv) both the increases in [Na+]i and cell volume were blocked by a Na+-K+-2Cl- co-transporter (NKCCl) inhibitor, bumetanide, or by a Na+/H+ exchange (NHE) inhibitor, 5-(N-ethyl-N-isopropyl) amiloride; and (v) spironolactone by itself increased in [Na+]i and cell volume. In conclusion, aldosterone rapidly increased [Na+]i and cell volume via NKCC1 and NHE, whereas there were no changes in CaT or myocardial contractility. Hence the non-genomic effects of aldosterone may be related to cell swelling rather than the increase in contractility. 相似文献
139.
Retinal progenitor cells are believed to display altered proliferation and differentiation during retinal development, suggesting that retinal progenitor cell populations are not homogeneous. However, the composition of progenitor cell populations is not known, due in part to the lack of known surface markers identifying distinct stages of retinal progenitor cells. We found a dramatic change in the expression profile of the cell surface antigens c-kit and stage-specific embryonic antigen-1 (SSEA-1) in retinal progenitor cells during development. While SSEA-1 was expressed early in development, c-kit expression peaked in late stage progenitor cells. The identification of these developmental markers enabled us to characterize distinct sub-populations of retinal progenitor cells. Progenitor cell subpopulations expressing either SSEA-1, c-kit, or both showed different proliferation and differentiation abilities. Although SSEA-1-positive cells were augmented by beta-catenin signaling, c-kit-positive cells were positively regulated by Notch signaling. Taken together, our data suggest that c-kit and SSEA-1 can be used to spatiotemporally differentiate retinal progenitor populations that have intrinsically distinct characteristics. Prolonged expression of c-kit by a retrovirus resulted in the promotion of proliferation and the appearance of nestin-positive cells in the presence of the c-kit ligand, stem cell factor (SCF). This suggests a role for c-kit, Notch, and the beta-catenin signaling network in retinal development. 相似文献
140.
Ahuja P Perriard E Pedrazzini T Satoh S Perriard JC Ehler E 《Experimental cell research》2007,313(6):1270-1283
Cardiomyocytes stop dividing after birth and postnatal heart growth is only achieved by increase in cell volume. In some species, cardiomyocytes undergo an additional incomplete mitosis in the first postnatal week, where karyokinesis takes place in the absence of cytokinesis, leading to binucleation. Proteins that regulate the formation of the actomyosin ring are known to be important for cytokinesis. Here we demonstrate for the first time that small GTPases like RhoA along with their downstream effectors like ROCK I, ROCK II and Citron Kinase show a developmental stage specific expression in heart, with high levels being expressed in cardiomyocytes only at stages when cytokinesis still occurs (i.e. embryonic and perinatal). This suggests that downregulation of many regulatory and cytoskeletal components involved in the formation of the actomyosin ring may be responsible for the uncoupling of cytokinesis from karyokinesis in rodent cardiomyocytes after birth. Interestingly, when the myocardium tries to adapt to the increased workload during pathological hypertrophy a re-expression of proteins involved in DNA synthesis and cytokinesis can be detected. Nevertheless, the adult cardiomyocytes do not appear to divide despite this upregulation of the cytokinetic machinery. The inability to undergo complete division could be due to the presence of stable, highly ordered and functional sarcomeres in the adult myocardium or could be because of the inefficiency of degradation pathways, which facilitate the division of differentiated embryonic cardiomyocytes by disintegrating myofibrils. 相似文献