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71.
Koji Ando Shigetomo Fukuhara Takahiro Moriya Yutaro Obara Norimichi Nakahata Naoki Mochizuki 《The Journal of cell biology》2013,202(6):901-916
Reorganization of the actin cytoskeleton is responsible for dynamic regulation of endothelial cell (EC) barrier function. Circumferential actin bundles (CAB) promote formation of linear adherens junctions (AJs) and tightening of EC junctions, whereas formation of radial stress fibers (RSF) connected to punctate AJs occurs during junction remodeling. The small GTPase Rap1 induces CAB formation to potentiate EC junctions; however, the mechanism underlying Rap1-induced CAB formation remains unknown. Here, we show that myotonic dystrophy kinase–related CDC42-binding kinase (MRCK)-mediated activation of non-muscle myosin II (NM-II) at cell–cell contacts is essential for Rap1-induced CAB formation. Our data suggest that Rap1 induces FGD5-dependent Cdc42 activation at cell–cell junctions to locally activate the NM-II through MRCK, thereby inducing CAB formation. We further reveal that Rap1 suppresses the NM-II activity stimulated by the Rho–ROCK pathway, leading to dissolution of RSF. These findings imply that Rap1 potentiates EC junctions by spatially controlling NM-II activity through activation of the Cdc42–MRCK pathway and suppression of the Rho–ROCK pathway. 相似文献
72.
Tsutomu Tanaka Sayoko Matsumoto Mari Yamada Ryosuke Yamada Fumio Matsuda Akihiko Kondo 《Applied microbiology and biotechnology》2013,97(10):4343-4352
Here, we demonstrate display of beta-glucosidase (BGL) on the surface of Schizosaccharomyces pombe cells using novel anchor proteins. A total of four candidate anchor proteins (SPBC21D10.06c, SPBC947.04, SPBC19C7.05, and SPBC359.04c) were selected from among almost all of S. pombe membrane proteins. The C-terminus of each anchor protein was genetically fused to the N-terminus of BGL, and the fusion protein was expressed using S. pombe as a host. The highest cell surface-associated BGL activity (107 U/105 cells was achieved with SPBC359.04c serving as the anchor, followed by SPBC947.04 (44 U/105 cells) and SPBC21D10.06c (38 U/105 cells). S. pombe displaying BGL with SPBC359.04c as an anchor showed the highest growth on 2 % cellobiose (10.7?×?107 cells/mL after 41 h of cultivation from an initial density of 0.1?×?107 cells/mL). Additionally, culturing BGL-displaying S. pombe in medium containing cellobiose as the sole carbon source did not affect protein expression, and ethanol fermentation from cellobiose was successfully demonstrated using BGL-displaying S. pombe. This is the first report describing a cell surface display system for the functionalization of S. pombe. 相似文献
73.
Claudia Leoni Malgorzata Pietrzykowska Anett Z. Kiss Marjaana Suorsa Luigi R. Ceci Eva‐Mari Aro Stefan Jansson 《The Plant journal : for cell and molecular biology》2013,76(2):236-246
Light‐harvesting complex II (LHCII) contains three highly homologous chlorophyll‐a/b‐binding proteins (Lhcb1, Lhcb2 and Lhcb3), which can be assembled into both homo‐ and heterotrimers. Lhcb1 and Lhcb2 are reversibly phosphorylated by the action of STN7 kinase and PPH1/TAP38 phosphatase in the so‐called state‐transition process. We have developed antibodies that are specific for the phosphorylated forms of Lhcb1 and Lhcb2. We found that Lhcb2 is more rapidly phosphorylated than Lhcb1: 10 sec of ‘state 2 light’ results in Lhcb2 phosphorylation to 30% of the maximum level. Phosphorylated and non‐phosphorylated forms of the proteins showed no difference in electrophoretic mobility and dephosphorylation kinetics did not differ between the two proteins. In state 2, most of the phosphorylated forms of Lhcb1 and Lhcb2 were present in super‐ and mega‐complexes that comprised both photosystem (PS)I and PSII, and the state 2‐specific PSI–LHCII complex was highly enriched in the phosphorylated forms of Lhcb2. Our results imply distinct and specific roles for Lhcb1 and Lhcb2 in the regulation of photosynthetic light harvesting. 相似文献
74.
Keiichi Konoki Tatsuya Onoda Sachie Furumochi Yuko Cho Mari Yotsu-Yamashita Takeshi Yasumoto 《Bioorganic & medicinal chemistry letters》2013,23(21):5833-5835
The binding between [24-3H]okadaic acid (OA) and a recombinant OA binding protein OABP2.1 was examined using various OA analog, including methyl okadaate, norokadanone, 7-deoxy OA, and 14,15-dihydro OA, 7-O-palmitoyl DTX1, to investigate the structure activity relationship. Among them, 7-O-palmitoyl DTX1, which is one of the diarrhetic shellfish poisoning (DSP) toxins identified in shellfish, displayed an IC50 for [24-3H]OA binding at 51 ± 6.3 nM (Mean ± SD). In addition, a synthetic compound, N-pyrenylmethyl okadamide, exhibited its IC50 at 10 ± 2.9 nM (Mean ± SD). These results suggested that the recombinant OABP2.1 and the N-pyrenylmethyl okadamide might be core substances in a novel assay for the DSP toxins. 相似文献
75.
Yoshihiro Kato Motoji Kawasaki Tomohiro Nigo Shunya Nakamura Akira Fusano Yasuhiro Teranishi Mari N. Ito Takaaki Sumiyoshi 《Bioorganic & medicinal chemistry》2013,21(18):5851-5854
A series of 2,3-disubstituted pyridines were synthesized and evaluated for their PDE4 inhibitory activity. We successfully modified undesirable cyano group of initial lead compound 2 to 4-pyridyl group with improvement of in vitro efficacy and optimized the position of nitrogen atoms in pyridine moiety and alkylene linker. The most potent compound showed significant efficacy in animal models of asthma and inflammation. 相似文献
76.
Hidehiro Hayashi Junko Ishikawa-Sakurai Mari Murai-Hatano Arifa Ahamed Matsuo Uemura 《Bioscience, biotechnology, and biochemistry》2013,77(9):1422-1429
During rice grain filling, grain moisture content and weight show dynamic changes. We focused on the expression of all 33 rice aquaporins in developing grains. Only two aquaporin genes, OsPIP2;1 and OsTIP3;1, were highly expressed in the period 10–25 days after heading (DAH). High-temperature treatment from 7 to 21 DAH abolished the dynamic up-regulation of OsPIP2;1 in the period 15–20 DAH, whereas OsTIP3;1 expression was not affected. Immunohistochemical analysis revealed that OsPIP2;1 was present in the starchy endosperm, nucellar projection, nucellar epidermis, and dorsal vascular bundles, but not in the aleurone layer. OsTIP3;1 was present in the aleurone layer and starchy endosperm. Water transport activity of recombinant OsTIP3;1 was low, in contrast to the high activity of recombinant OsPIP2;1 we reported previously. Our data suggest that OsPIP2;1 and OsTIP3;1 have distinct roles in developing grains. 相似文献
77.
Chihiro Handa Tadahiro Okubo Aogu Yoneyama Masashi Nakamura Mari Sakaguchi Narumi Takahashi Mayumi Okamoto Ayumi Tanaka-Oda Tanaka Kenzo Tomoaki Ichie Takao Itioka 《Journal of plant research》2013,126(1):73-79
Macaranga myrmecophytes (ant-plants) provide their partner symbiotic ants (plant-ants) with food bodies as their main food, and they are protected by the plant-ants from herbivores. The amount of resource allocated to food bodies determines the plant-ant colony size and consequently determines the intensity of ant defense (anti-herbivore defense by plant-ants). As constraints in resource allocation change as plants grow, the plant-ant colony size is hypothesized to change with the ontogenesis of Macaranga myrmecophyte. To determine the ontogenetic change in the relative size of the plant-ant colony, we measured the dry weights of the whole plant-ant colony and all of the aboveground parts of trees at various ontogenetic stages for a myrmecophytic species (Macaranga beccariana) in a Bornean lowland tropical rain forest. Ant biomass increased as plant biomass increased. However, the rate of increase gradually declined, and the ant biomass appeared to reach a ceiling once trees began to branch. The ant/plant biomass ratio consistently decreased as plant biomass increased, with the rate of decrease gradually accelerating. We infer that the ontogenetic reduction in ant/plant biomass ratio is caused by an ontogenetic change in resource allocation to food rewards for ants related to the physiological changes accompanying the beginning of branching. 相似文献
78.
Mari M. S. G. Cardena ?ndrea Ribeiro-dos-Santos Sidney Santos Alfredo J. Mansur Alexandre C. Pereira Cintia Fridman 《PloS one》2013,8(4)
In populations that have a high degree of admixture, such as in Brazil, the sole use of ethnicity self-declaration information is not a good method for classifying individuals regarding their ethnicity. Here, we evaluate the relationship of self-declared ethnicities with genomic ancestry and mitochondrial haplogroups in 492 individuals from southeastern Brazil. Mitochondrial haplogroups were obtained by analyzing the hypervariable regions of the mitochondrial DNA (mtDNA), and the genomic ancestry was obtained using 48 autosomal insertion-deletion ancestry informative markers (AIM). Of the 492 individuals, 74.6% self-declared as White, 13.8% as Brown and 10.4% as Black. Classification of the mtDNA haplogroups showed that 46.3% had African mtDNA, and the genomic ancestry analysis showed that the main contribution was European (57.4%). When we looked at the distribution of mtDNA and genomic ancestry according to the self-declared ethnicities from 367 individuals who self-declared as White, 37.6% showed African mtDNA, and they had a high contribution of European genomic ancestry (63.3%) but also a significant contribution of African ancestry (22.2%). Of the 68 individuals who self-declared as Brown, 25% showed Amerindian mtDNA and similar contribution of European and African genomic ancestries. Of the 51 subjects who self-declared as black, 80.4% had African mtDNA, and the main contribution of genomic ancestry was African (55.6%), but they also had a significant proportion of European ancestry (32.1%). The Brazilian population had a uniform degree of Amerindian genomic ancestry, and it was only with the use of genetic markers (autosomal or mitochondrial) that we were able to capture Amerindian ancestry information. Additionally, it was possible to observe a high degree of heterogeneity in the ancestry for both types of genetic markers, which shows the high genetic admixture that is present in the Brazilian population. We suggest that in epidemiological studies, the use of these methods could provide complementary information. 相似文献
79.
Leydis Zamora José F. Fernández-Garayzábal Cristina Sánchez-Porro Mari Angel Palacios Edward R. B. Moore Lucas Domínguez Antonio Ventosa Ana I. Vela 《PloS one》2013,8(6)
Five strains (1126-1H-08T, 51B-09, 986-08, 1084B-08 and 424-08) were isolated from diseased rainbow trout. Cells were Gram-negative rods, 0.7 µm wide and 3 µm long, non-endospore-forming, catalase and oxidase positive. Colonies were circular, yellow-pigmented, smooth and entire on TGE agar after 72 hours incubation at 25°C. They grew in a temperature range between 15°C to 30°C, but they did not grow at 37°Cor 42°C. Based on 16S rRNA gene sequence analysis, the isolates belonged to the genus Flavobacterium. Strain 1126-1H-08T exhibited the highest levels of similarity with Flavobacterium oncorhynchi CECT 7678T and Flavobacterium pectinovorum DSM 6368T (98.5% and 97.9% sequence similarity, respectively). DNA–DNA hybridization values were 87 to 99% among the five isolates and ranged from 21 to 48% between strain 1126-1H-08T, selected as a representative isolate, and the type strains of Flavobacterium oncorhynchi CECT 7678T and other phylogenetic related Flavobacterium species. The DNA G+C content of strain 1126-1H-08T was 33.2 mol%. The predominant respiratory quinone was MK-6 and the major fatty acids were iso-C15∶0 and C15∶0. These data were similar to those reported for Flavobacterium species. Several physiological and biochemical tests differentiated the novel bacterial strains from related Flavobacterium species. Phylogenetic, genetic and phenotypic data indicate that these strains represent a new species of the genus Flavobacterium, for which the name Flavobacterium plurextorum sp. nov. was proposed. The type strain is 1126-1H-08T ( = CECT 7844T = CCUG 60112T). 相似文献
80.
Yong Woo Kim Jin Wook Jeoung Dai Woo Kim Michael J. A. Girard Jean Martial Mari Ki Ho Park Dong Myung Kim 《PloS one》2016,11(3)