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81.
Gerit Bethke Amanda Thao Guangyan Xiong Baohua Li Nicole E. Soltis Noriyuki Hatsugai Rachel A. Hillmer Fumiaki Katagiri Daniel J. Kliebenstein Markus Pauly Jane Glazebrook 《The Plant cell》2016,28(2):537-556
Plant cell walls are important barriers against microbial pathogens. Cell walls of Arabidopsis thaliana leaves contain three major types of polysaccharides: cellulose, various hemicelluloses, and pectins. UDP-d-galacturonic acid, the key building block of pectins, is produced from the precursor UDP-d-glucuronic acid by the action of glucuronate 4-epimerases (GAEs). Pseudomonas syringae pv maculicola ES4326 (Pma ES4326) repressed expression of GAE1 and GAE6 in Arabidopsis, and immunity to Pma ES4326 was compromised in gae6 and gae1 gae6 mutant plants. These plants had brittle leaves and cell walls of leaves had less galacturonic acid. Resistance to specific Botrytis cinerea isolates was also compromised in gae1 gae6 double mutant plants. Although oligogalacturonide (OG)-induced immune signaling was unaltered in gae1 gae6 mutant plants, immune signaling induced by a commercial pectinase, macerozyme, was reduced. Macerozyme treatment or infection with B. cinerea released less soluble uronic acid, likely reflecting fewer OGs, from gae1 gae6 cell walls than from wild-type Col-0. Although both OGs and macerozyme-induced immunity to B. cinerea in Col-0, only OGs also induced immunity in gae1 gae6. Pectin is thus an important contributor to plant immunity, and this is due at least in part to the induction of immune responses by soluble pectin, likely OGs, that are released during plant-pathogen interactions. 相似文献
82.
In central Japan, Harmonia yedoensis is a specialist ladybird that is confined to pine tree habitats, whereas its sibling species Harmonia axyridis is a generalist that feeds on a wide range of aphid species in nature. Interestingly, H. axyridis is not distributed in the Ryukyu Archipelago, southern Japan. We hypothesized that the ecological niche of H. yedoensis should be wider in the Ryukyu Archipelago, where its competitor species in central Japan, H. axyridis, is absent. We undertook fieldwork and a survey of published works to examine habitat utilization by H. yedoensis in the Ryukyu Archipelago. We found that H. yedoensis adults in the Ryukyu Archipelago visited several kinds of deciduous trees, including wild tamarind, Chinese hibiscus, Taiwan cherry and Malayan banyan, as well as pine trees. These observations suggest that habitat generalization has occurred in H. yedoensis in the Ryukyu Archipelago, where it does not compete with H. axyridis. 相似文献
83.
Genyan Liu Huaguang Li Jiaying Shi Wenjie Wang Kenjiro Furuta Di Liu Chunqing Zhao Fumiyo Ozoe Xiulian Ju Yoshihisa Ozoe 《Bioorganic & medicinal chemistry》2019,27(2):416-424
Competitive antagonists (CAs) of ionotropic GABA receptors (GABARs) reportedly exhibit insecticidal activity and have potential for development as novel insecticides for overcoming emerging resistance to traditional GABAR-targeting insecticides. Our previous studies demonstrated that 4,5-disubstituted 3-isoxazolols or 3-isothiazolols are an important class of insect GABAR CAs. In the present study, we synthesized a series of 4-aryl-5-carbamoyl-3-isoxazolols and examined their antagonism of insect GABARs expressed in Xenopus oocytes. Several of these 3-isoxazolols exhibited potent antagonistic activities against housefly and common cutworm GABARs, with IC50 values in the low-micromolar range in both receptors. 4-(3-Amino-4-methylphenyl)-5-carbamoyl-3-isoxazolol (3u) displayed the highest antagonism, with IC50 values of 2.0 and 0.9?μM in housefly and common cutworm GABARs, respectively. Most of the synthesized 3-isoxazolols showed moderate larvicidal activities against common cutworms, with more than 50% mortality at 100?μg/g. These results indicate that 4-monocyclic aryl-5-carbamoyl-3-isoxazolol is a promising scaffold for insect GABAR CA discovery and provide important information for the design and development of GABAR-targeting insecticides with a novel mode of action. 相似文献
84.
85.
Asuka Takaishi Andrey E. Kozhevnikov Zoya V. Kozhevnikova Hajime Ikeda Noriyuki Fujii Akiko Soejima 《Ecology and evolution》2019,9(12):7262-7272
The genetic diversity and structure of Pulsatilla cernua, a continental‐grassland relict, were investigated using variations in chloroplast DNA (cpDNA) and microsatellites of nuclear DNA. In the analyses of three cpDNA regions, 17 haplotypes were found in 24 populations of P. cernua from Japan, Korea, and Russia. Although the route and time of migration between the continent of Asia and Japan could not be well resolved, the cpDNA haplotype network suggests the existence of several ancient lineages in Japan and a recent secondary migration from Japan to the continent. Microsatellite analyses did not indicate genetic structure among the Japanese populations, indicating the existence of gene flow across the distribution area until recently. These results indicate that the present fragmentation of P. cernua in Japan may reflect a rapid, recent reduction from a previously large, continuous distribution. 相似文献
86.
87.
Urai M Yoshizaki H Anzai H Ogihara J Iwabuchi N Harayama S Sunairi M Nakajima M 《Carbohydrate research》2007,342(7):933-942
Rhodococcus erythropolis PR4 is a marine bacterium that can degrade various alkanes including pristane, a C(19) branched alkane. This strain produces a large quantity of extracellular polysaccharides, which are assumed to play an important role in the hydrocarbon tolerance of this bacterium. The strain produced two acidic extracellular polysaccharides, FR1 and FR2, and the latter showed emulsifying activity toward clove oil, whereas the former did not. FR2 was composed of D-galactose, D-glucose, D-mannose, D-glucuronic acid, and pyruvic acid at a molar ratio of 1:1:1:1:1, and contained 2.9% (w/w) stearic acid and 4.3% (w/w) palmitic acid attached via ester bonds. Therefore, we designated FR2 as a PR4 fatty acid-containing extracellular polysaccharide or FACEPS. The chemical structure of the PR4 FACEPS polysaccharide chain was determined by 1D (1)H and (13)C NMR spectroscopies as well as by 2D DQF-COSY, TOCSY, HMQC, HMBC, and NOESY experiments. The sugar chain of PR4 FACEPS was shown to consist of tetrasaccharide repeating units having the following structure: [structure: see text]. 相似文献
88.
Background
This paper reports on the modification of the Parental Nurturance Scale (PNS), translation of the modified version (PNSM) from English to Japanese, and equivalence assessment between the PNSM and the translated version (PNSM-J). The PNS was modified so as to enable its use in nurturance studies where the prime source of nurturance might vary between respondents. 相似文献89.
Sakata E Yamaguchi Y Miyauchi Y Iwai K Chiba T Saeki Y Matsuda N Tanaka K Kato K 《Nature structural & molecular biology》2007,14(2):167-168
Although cullin-1 neddylation is crucial for the activation of SCF ubiquitin E3 ligases, the underlying mechanisms for NEDD8-mediated activation of SCF remain unclear. Here we demonstrate by NMR and mutational studies that NEDD8 binds the ubiquitin E2 (UBC4), but not NEDD8 E2 (UBC12). Our data imply that NEDD8 forms an active platform on the SCF complex for selective recruitment of ubiquitin-charged E2s in collaboration with RBX1, and thereby upregulates the E3 activity. 相似文献
90.
Hiroyuki Sonoda Haku Iizuka Sho Ishiwata Daisuke Tsunoda Masako Abe Kenji Takagishi Hirotaka Chikuda Noriyuki Koibuchi Noriaki Shimokawa 《Journal of cellular biochemistry》2019,120(9):15007-15017
Although congenital scoliosis is defined as a genetic disease characterized by a congenital and abnormal curvature of the spinal vertebrae, our knowledge of the genetic underpinnings of the disease is insufficient. We herein show that the downregulation of the retinol-retinoic acid metabolism pathway is involved in the pathogenesis of congenital scoliosis. By analyzing DNA microarray data, we found that the expression levels of genes associated with the retinol metabolism pathway were decreased in the lumbar spine of Ishibashi rats (IS), a rat model of congenital kyphoscoliosis. The expression of Adh1 and Aldh1a2 (alcohol dehydrogenase), two enzymes that convert retinol to retinoic acid in this pathway, were decreased at both the gene and protein levels. Rarα, a receptor of retinoic acid and bone morphogenetic protein 2, which play a central role in bone formation and are located downstream of this pathway, were also downregulated. Interestingly, the serum retinol levels of IS rats were higher than those of wild-type control rats. These results indicate that the adequate conversion from retinol to retinoic acid is extremely important in the regulation of normal bone formation and it may also be a key factor for understanding the pathogenesis of congenital scoliosis. 相似文献