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171.
Moriguchi R Matsuoka C Suyama A Matsuoka K 《Bioscience, biotechnology, and biochemistry》2011,75(5):994-996
Plant specific O-glycosylation of proteins includes the attachment of arabinogalactan to hydroxyproline (Hyp) residues. These Hyp residues are generated from peptidyl proline residues by the action of prolyl 4-hydroxylase which requires the ferrous ion. We investigated the effect of the ferrous chelator, 2,2'-dipyridyl on tobacco plants, and found that such treatment reduced the arabinogalactosylation of proteins. 相似文献
172.
Tabata M Endo R Ito M Ohtsubo Y Kumar A Tsuda M Nagata Y 《Bioscience, biotechnology, and biochemistry》2011,75(3):466-472
A γ-hexachlorocyclohexane (HCH)-degrading bacterium, Sphingomonas sp. MM-1, was isolated from soil contaminated with HCH isomers. Cultivation of MM-1 in the presence of γ-HCH led to the detection of five γ-HCH metabolites, γ-pentachlorocyclohexene, 2,5-dichloro-2,5-cyclohexadiene-1,4-diol, 2,5-dichlorohydroquinone, 1,2,4-trichlorobenzene, and 2,5-dichlorophenol, strongly suggesting that MM-1 has the lin genes for γ-HCH degradation originally identified in the well-studied γ-HCH-degrading strain Sphingobium japonicum UT26. Southern blot, PCR amplification, and sequencing analyses indicated that MM-1 has seven lin genes for the conversion of γ-HCH to β-ketoadipate (six structural genes, linA to linF, and one regulatory gene, linR). MM-1 carried four plasmids, of 200, 50, 40, and 30 kb. Southern blot analysis revealed that all seven lin genes were dispersed across three of the four plasmids, and that IS6100, often found close to the lin genes, was present on all four plasmids. 相似文献
173.
One key event in the programmed cell death is nuclear DNA fragmentation. We investigated the timing of nuclear DNA fragmentation
during the cell death of short-lived ray tracheids in Pinus densiflora using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. Fluorescence due to TUNEL
was detected only in deformed nuclei that lacked obvious chromatin in ray tracheids that were adjacent to ray tracheids that
no longer contained nuclei. Our observations revealed that nuclear DNA fragmentation occurred only at the final stage of cell
death in ray tracheids in situ. 相似文献
174.
Harada T Kobayashi R Wada K Nishihara R Kondo A Akimitsu O Noji T Taniwaki N Nakade M Krejci M Takeuchi H 《Chronobiology international》2011,28(7):638-642
Several studies suggest that season of birth differentially affects the physiological characteristics of humans. Those living at relatively high latitude, such as Canada, Spain, and Italy (44°N-45°N), and born in the fall tended to be "morning-type" persons in comparison to those born in other seasons. There are relatively little data on the affect of season of birth on people residing at low latitude. Here the authors show that at low latitude, Kochi, Japan (33°N), the effect of season of birth on the morningness chronotype is confined to young children aged 1-12 yrs, disappearing in elderly persons. Only female participants aged 2-12 yrs born in the fall, especially in November, were significantly morning-typed (p < .001) in comparison to those born in the other seasons, whereas there were no such significant season-of-birth differences in morningness-eveningness preference among male participants. Moreover, both female and male participants aged 13-25 yrs showed no significant seasonal differences in morningness-eveningness preference. The small effects detected in this study might be due to smaller seasonal change in day length at the relatively lower latitude of Kochi. 相似文献
175.
Tanaka R Kato M Suzuki T Nakazaki A Nozaki E Gotoh M Murakami-Murofushi K Kobayashi S 《Bioorganic & medicinal chemistry letters》2011,21(14):4180-4182
The efficient synthesis of 3-O-thia-cPAs (4a-d), sulfur analogues of cyclic phosphatidic acid (cPA), has been achieved. The key step of the synthesis is an intramolecular Arbuzov reaction to construct the cyclic thiophosphate moiety. The present synthetic route enables the synthesis of 4a-d in only four steps from the commercially available glycidol. Preliminary biological experiments showed that 4a-d exhibited a similar inhibitory effect on autotaxin (ATX) as original cPA. 相似文献
176.
Futahashi R Tanaka K Matsuura Y Tanahashi M Kikuchi Y Fukatsu T 《Insect biochemistry and molecular biology》2011,41(3):191-196
During the maturation of insect cuticle, protein-protein and protein-chitin crosslinkages are formed by the action of diphenoloxidases. Two types of diphenoloxidases, laccases and tyrosinases, are present in the insect cuticle. In coleopteran and hymenopteran insects, laccase2 gene has been identified as encoding an enzyme principally responsible for cuticular pigmentation and hardening, whereas biological roles of laccase genes in hemimetabolous insects remain to be established. Here we identified laccase2 genes from three hemipteran stinkbugs, Riptortus pedestris (Alydidae), Nysius plebeius (Lygaeidae) and Megacopta punctatissima (Plataspidae). In R. pedestris, laccase2 gene was highly expressed in epidermal tissues prior to molting. When the gene expression was suppressed by an RNA interference technique, cuticular pigmentation after molting were blocked depending on the dose of injected double-stranded RNA targeting the laccase2 gene. Similar results were obtained for N. plebeius and M. punctatissima. In all the stinkbug species, injecting 20 ng of double-stranded RNA was sufficient to prevent the cuticular maturation. These results indicate that laccase2 gene is generally required for cuticular pigmentation in different stinkbug families, highlighting its conserved biological function across diverse insect taxa. 相似文献
177.
Takasawa R Tao A Saeki K Shionozaki N Tanaka R Uchiro H Takahashi S Yoshimori A Tanuma S 《Bioorganic & medicinal chemistry letters》2011,21(14):4337-4342
The human glyoxalase I (hGLO I), which is a rate-limiting enzyme in the pathway for detoxification of apoptosis-inducible methylglyoxal (MG), has been expected as an attractive target for the development of new anti-cancer drugs. We have previously identified a natural compound myricetin as a substrate transition-state (Zn2+-bound MG-glutathione (GSH) hemithioacetal) mimetic inhibitor of hGLO I. Here, we constructed a hGLO I/inhibitor 4-point pharmacophore based on the binding mode of myricetin to hGLO I. Using this pharmacophore, in silico screening of chemical library was performed by docking study. Consequently, a new type of compound, which has a unique benzothiazole ring with a carboxyl group, named TLSC702, was found to inhibit hGLO I more effectively than S-p-bromobenzylglutathione (BBG), a well-known GSH analog inhibitor. The computational simulation of the binding mode indicates the contribution of Zn2+-chelating carboxyl group of TLSC702 to the hGLO I inhibitory activity. This implies an important scaffold-hopping of myricetin to TLSC702. Thus, TLSC702 may be a valuable seed compound for the generation of a new lead of anti-cancer pharmaceuticals targeting hGLO I. 相似文献
178.
Ayumu Sugiura Ryo Yonashiro Toshifumi Fukuda Nobuko Matsushita Shun Nagashima Ryoko Inatome Shigeru Yanagi 《Mitochondrion》2011,11(1):139-146
Expansion of a polyglutamine tract in ataxin-3 (polyQ) causes Machado–Joseph disease, a late-onset neurodegenerative disorder characterized by ubiquitin-positive aggregate formation. Several lines of evidence demonstrate that polyQ also accumulates in mitochondria and causes mitochondrial dysfunction. To uncover the mechanism of mitochondrial quality-control via the ubiquitin–proteasome pathway, we investigated whether MITOL, a novel mitochondrial ubiquitin ligase localized in the mitochondrial outer membrane, is involved in the degradation of pathogenic ataxin-3 in mitochondria. In this study, we used N-terminal-truncated pathogenic ataxin-3 with a 71-glutamine repeat (ΔNAT-3Q71) and found that MITOL promoted ΔNAT-3Q71 degradation via the ubiquitin–proteasome pathway and attenuated mitochondrial accumulation of ΔNAT-3Q71. Conversely, MITOL knockdown induced an accumulation of detergent-insoluble ΔNAT-3Q71 with large aggregate formation, resulting in cytochrome c release and subsequent cell death. Thus, MITOL plays a protective role against polyQ toxicity, and thereby may be a potential target for therapy in polyQ diseases. Our findings indicate a protein quality-control mechanism at the mitochondrial outer membrane via a MITOL-mediated ubiquitin–proteasome pathway. 相似文献
179.
Ojika M Molli SD Kanazawa H Yajima A Toda K Nukada T Mao H Murata R Asano T Qi J Sakagami Y 《Nature chemical biology》2011,7(9):591-593
The heterothallic species of the agricultural pest Phytophthora use mating hormones α1 and α2 to regulate their sexual reproduction. Here we describe the absolute stereostructure of the second mating hormone α2 as defined by spectroscopic analysis and total synthesis. We have uncovered not only the interspecies universality of α hormones but also the pathway by which α2 is biosynthesized from phytol by A2-mating type strains and metabolized to α1 by A1 strains. 相似文献
180.
Remi Nakagawa Masahiro Kurushima Masaaki Matsui Ryouichi Nakamura Takafumi Kubo Ryo Funada 《In vitro cellular & developmental biology. Plant》2011,47(4):480-487
Effects of polyamines on the development of embryonal-suspensor masses (ESMs) and the formation of somatic embryos were examined
in an effort to improve the frequency of somatic embryogenesis in Picea glehnii. Exogenous spermidine at 100 and 300 μM promoted the elongation of suspensors and the formation of somatic embryos. Exogenous
putrescine at 100 μM increased the number of somatic embryos and decreased the time required for formation of somatic embryos.
Thus, exogenous polyamines improved the maturation capacity of ESMs and promoted the formation of somatic embryos in P. glehnii. Light microscopy revealed that ESMs with high maturation capacity consisted of the three following cells: round or oval
cells, elongated cells, and protean cells. These components might be related to the capacity for formation of somatic embryos. 相似文献