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51.
Basic fibroblast growth factor (FGF-2) mitogenic activities of sulfonated poly(gamma-glutamic acid) (gamma-PGA-S) were investigated with chlorate-treated L929 fibroblast culture tests. When 72% of the carboxyl groups in gamma-PGA were sulfonated (gamma-PGA-S72), cell numbers reached a maximum. The activity of gamma-PGA-S72 was higher than that of gamma-PGA and synthetic heparinoids and was almost comparable to that of heparin. Cytotoxicity of gamma-PGA-S72 was not observed, regardless of the degree of sulfonation. FGF-2-protective effects of gamma-PGA-S72 against acid and thermal inactivation were also evaluated, and gamma-PGA-S72 showed higher FGF-2-protective effects in comparison to nonsulfonated gamma-PGA. The steric structures of various sulfonated gamma-PGA-Ss were analyzed by molecular modeling (molecular orbital method (MOPAC)) and indicated that gamma-PGA-Ss are helical in vacuo. Results from MOPAC and the molecular mechanics method (MM2) demonstrated that electrostatic interactions can take place between sulfonic and carboxyl groups of gamma-PGA-S and basic amino acid residues in FGF-2. gamma-PGA-S72 can interact with FGF-2 strongly. 相似文献
52.
Osmotic stress in barley regulates expression of a different set of genes than salt stress does 总被引:1,自引:0,他引:1
Ueda A Kathiresan A Inada M Narita Y Nakamura T Shi W Takabe T Bennett J 《Journal of experimental botany》2004,55(406):2213-2218
Under high salt conditions, plant growth is severely inhibited due to both osmotic and ionic stresses. In an effort to dissect genes and pathways that respond to changes in osmotic potential under salt stress, the expression patterns were compared of 460 non-redundant salt-responsive genes in barley during the initial phase under osmotic versus salt stress using cDNA microarrays with northern blot and real-time RT-PCR analyses. Out of 52 genes that were differentially expressed under osmotic stress, 11, such as the up-regulated genes for pyrroline-5-carboxylate synthetase, betaine aldehyde dehydrogenase 2, plasma membrane protein 3, and the down-regulated genes for water channel 2, heat shock protein 70, and phospholipase C, were regulated in a virtually identical manner under salt stress. These genes were involved in a wide range of metabolic and signalling pathways suggesting that, during the initial phase under salt stress, several of the cellular responses are mediated by changes in osmotic potential. 相似文献
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54.
Koilkonda P Sato S Tabata S Shirasawa K Hirakawa H Sakai H Sasamoto S Watanabe A Wada T Kishida Y Tsuruoka H Fujishiro T Yamada M Kohara M Suzuki S Hasegawa M Kiyoshima H Isobe S 《Molecular breeding : new strategies in plant improvement》2012,30(1):125-138
Large-scale development of expressed sequence tag simple sequence repeat (EST-SSR) markers was performed in peanut (Arachis hypogaea L.) to obtain more informative genetic markers. A total of 10,102 potential non-redundant EST sequences, including 3,445 contigs and 6,657 singletons, were generated from cDNA libraries of the gynophore, roots, leaves and seedlings. A total of 3,187 primer pairs were designed on flanking regions of SSRs, some of which allowed one and two base mismatches. Among the 3,187 markers generated, 2,540 (80%) were trinucleotide repeats, 302 (9%) were dinucleotide repeats, and 345 (11%) were tetranucleotide repeats. Pre-polymorphic analyses of 24 Arachis accessions were performed using 10% polyacrylamide gels. A total of 1,571 EST-SSR markers showing clear polymorphisms were selected for further polymorphic analysis with a Fluoro-fragment Analyzer. The 16 Arachis accessions examined included cultivated peanut varieties as well as diploid species with the A or B genome. Altogether 1,281 (81.5%) of the 1,571 markers were polymorphic among the 16 accessions, and 366 (23.3%) were polymorphic among the 12 cultivated varieties. Diversity analysis was performed and the genotypes of all 16 Arachis accessions showed similarity coefficients ranging from 0.37 to 0.97. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11032-011-9604-8) contains supplementary material, which is available to authorized users. 相似文献
55.
Kishida T 《PloS one》2008,3(6):e2385
The olfactory receptor (OR) multigene family is responsible for the sense of smell in vertebrate species. OR genes are scattered widely in our chromosomes and constitute one of the largest gene families in eutherian genomes. Some previous studies revealed that eutherian OR genes diverged mainly during early mammalian evolution. However, the exact period when, and the ecological reason why eutherian ORs strongly diverged has remained unclear. In this study, I performed a strict data mining effort for marsupial opossum OR sequences and bootstrap analyses to estimate the periods of chromosomal migrations and gene duplications of OR genes during tetrapod evolution. The results indicate that chromosomal migrations occurred mainly during early vertebrate evolution before the monotreme-placental split, and that gene duplications occurred mainly during early mammalian evolution between the bird-mammal split and marsupial-placental split, coinciding with the reduction of opsin genes in primitive mammals. It could be thought that the previous chromosomal dispersal allowed the OR genes to subsequently expand easily, and the nocturnal adaptation of early mammals might have triggered the OR gene expansion. 相似文献
56.
Kishida T Asada H Kubo K Sato YT Shin-Ya M Imanishi J Yoshikawa K Mazda O 《Journal of biotechnology》2008,133(2):201-207
57.
Tago R Yamauchi S Maruyama M Akiyama K Sugahara T Kishida T Koba Y 《Bioscience, biotechnology, and biochemistry》2008,72(4):1032-1037
The relationship between the antibacterial activity and structure of 9-O,9'-O-demethyl (+)-virgatusin (Virg 3) was examined. The conversion of hydroxy groups on the 9 and 9' positions to amino groups increased the activity. It was found that the 3'-methoxy group was more important for higher activity than the 4'-methoxy group on the 7'-phenyl group, and that the 3,4-methylenedioxy group on the 7-phenyl group was necessary for activity. 相似文献
58.
Irie O Kosaka T Kishida M Sakaki J Masuya K Konishi K Yokokawa F Ehara T Iwasaki A Iwaki Y Hitomi Y Toyao A Gunji H Teno N Iwasaki G Hirao H Kanazawa T Tanabe K Hiestand PC Malcangio M Fox AJ Bevan SJ Yaqoob M Culshaw AJ Hart TW Hallett A 《Bioorganic & medicinal chemistry letters》2008,18(19):5280-5284
We describe here orally active and brain-penetrant cathepsin S selective inhibitors, which are virtually devoid of hERG K(+) channel affinity, yet exhibit nanomolar potency against cathepsin S and over 100-fold selectivity to cathepsin L. The new non-peptidic inhibitors are based on a 2-cyanopyrimidine scaffold bearing a spiro[3.5]non-6-yl-methyl amine at the 4-position. The brain-penetrating cathepsin S inhibitors demonstrate potential clinical utility for the treatment of multiple sclerosis and neuropathic pain. 相似文献
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