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61.
Ishigamori H Hosokawa M Kohno H Tanaka T Miyashita K Takahashi K 《Molecular and cellular biochemistry》2005,275(1-2):127-133
18:1/docosahexaenoic acid (DHA)-containing phosphatidylethanolamine (PE) enhanced cell differentiation and growth inhibition of HL-60 induced by dibutyryl cAMP (dbcAMP) in a dose-dependent manner. The combined treatment of 200 μM dbcAMP and 50 μM 18:1/DHA-PE increased the NBT reducing activity, which is as an indicator of cell differentiation, to more than 75% from 40% of cells treated with 200 μM dbcAMP alone. In HL-60 cells treated with 50 μM 18:1/DHA-PE and 200 μM dbcAMP for 24 h, the expression level of c-jun mRNA and c-Jun protein were remarkably elevated compared to cells treated with dbcAMP alone. In contrast, there was no difference in the expression levels of c-fos mRNA and c-Fos protein between the combination of 18:1/DHA-PE + dbcAMP or dbcAMP alone. On the other hand, the combine treatment of 18:1/DHA-PE and dbcAMP markedly reduced the expression level of c-myc oncogene during 48 h incubation. The decreases of c-myc mRNA by 18:1/DHA-PE and/or dbcAMP was correlated with growth inhibition effect. Thus, 18:1/DHA-PE might enhance dbcAMP-induced HL-60 cell differentiation and growth inhibition by regulation of c-jun and c-myc mRNA and their products. 相似文献
62.
Nagai Y Nochi T Watanabe K Watanabe K Aso H Kitazawa H Matsuzaki M Ohwada S Yamaguchi T 《Cell and tissue research》2005,322(3):455-462
A pro-inflammatory cytokine, interleukin 18 (IL-18), induces intracellular expression of IL-1 and the release of IL-6. IL-1
and IL-6 has been detected in anterior pituitary cells, suggesting that IL-18 is produced in anterior pituitary cells and
may serve to aid immuno-endocrine regulation. In the present study, we addressed this hypothesis by investigating the intracellular
localization of IL-18 and its receptor in bovine anterior pituitary gland. IL-18 mRNA and its protein were detected in the
anterior pituitary gland by RT-PCR and Western blotting. In situ hybridization showed that IL-18 mRNA was expressed in the
anterior pituitary cells. Immunohistochemistry of IL-18 and specific hormones revealed the presence of IL-18 in somatotrophs.
Furthermore, the expression of GH mRNA in IL-18 immunoreactive cells was confirmed by immuno-laser microdissection. These
results first demonstrated that somatotrophs produced IL-18. Subsequently, the distribution of the IL-18 receptor alpha (IL-18Rα)
was investigated in order to understand IL-18 signaling among the anterior pituitary cells. Bovine IL-18Rα cDNA was partially
sequenced and detected in the anterior pituitary gland by RT-PCR. Immunohistochemistry of IL-18Rα, IL-18 and GH showed that
IL-18Rα was co-localized in IL-18 immunoreactive cells or somatotrophs. These data suggest that IL-18 acts on somatotrophs
as an immuno-endocrine mediator through the autocrine pathway.
This work was supported by a Grant-in-Aid for Scientific Research (B) (No.13460122) from the Ministry of Education, Science
and Culture of Japan 相似文献
63.
Recently we discovered a bacterial strain (MS-02-063) that produces large amounts of red pigment from coastal area of Nagasaki Prefecture, Japan. Comparative 16S rDNA gene sequencing analysis revealed that strain MS-02-063 was phylogenetically closely related to gamma-proteobacterium Hahella sp. MBIC 3957 that produces prodigiosin. However, some physiological and biochemical differences between strain MS-02-063 and Hahella sp. MBIC 3957 were observed. The red pigment (RP-063) produced by this isolate was highly purified from the culture supernatant. It was speculated that RP-063 might be prodigiosin-like pigment in physical properties and biological activities such as antibacterial and cytotoxic activity. Antibacterial activity of RP-063 was examined by an agar dilution method. The results indicated that RP-063 showed antibacterial activity for specific for pathogenic gram-positive bacteria such as Staphylococcus aureus. The potency of antibacterial activity against S. aureus was nearly equal to those of tetracycline. Moreover, RP-063 showed inhibition of the superoxide generation by 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated mouse macrophage RAW 264.7 cell line. Prodigiosin members have a wide variety of biological properties, including anticancer and antimalarial, etc. Especially, potent immunosuppressive properties have been reported for prodigiosin members with the mechanism of action different from that of the other well known immunosuppressors in atopic dermatitis therapy such as cyclosporin A, FK506 and rapamycin. It is suggested that RP-063 may be able to arrest the inflammation caused by superantigens secreted from S. aureus, which colonized skin on atopic dermatitis as well as suppression of activated lymphocyte proliferation and superoxide generation from leucocytes. 相似文献
64.
65.
Ammiraju JS Yu Y Luo M Kudrna D Kim H Goicoechea JL Katayose Y Matsumoto T Wu J Sasaki T Wing RA 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,111(8):1596-1607
The International Rice Genome Sequencing Project has recently announced the high-quality finished sequence that covers nearly
95% of the japonica rice genome representing 370 Mbp. Nevertheless, the current physical map of japonica rice contains 62 physical gaps corresponding to approximately 5% of the genome, that have not been identified/represented
in the comprehensive array of publicly available BAC, PAC and other genomic library resources. Without finishing these gaps,
it is impossible to identify the complete complement of genes encoded by rice genome and will also leave us ignorant of some
5% of the genome and its unknown functions. In this article, we report the construction and characterization of a tenfold
redundant, 40 kbp insert fosmid library generated by random mechanical shearing. We demonstrated its utility in refining the
physical map of rice by identifying and in silico mapping 22 gap-specific fosmid clones with particular emphasis on chromosomes
1, 2, 6, 7, 8, 9 and 10. Further sequencing of 12 of the gap-specific fosmid clones uncovered unique rice genome sequence
that was not previously reported in the finished IRGSP sequence and emphasizes the need to complete finishing of the rice
genome.
Fosmid library reported here is publicly available from our web site 相似文献
66.
Gu X Li C Wei W Lo V Gong S Li SH Iwasato T Itohara S Li XJ Mody I Heintz N Yang XW 《Neuron》2005,46(3):433-444
Expanded polyglutamine (polyQ) proteins in Huntington's disease (HD) as well as other polyQ disorders are known to elicit a variety of intracellular toxicities, but it remains unclear whether polyQ proteins can elicit pathological cell-cell interactions which are critical to disease pathogenesis. To test this possibility, we have created conditional HD mice expressing a neuropathogenic form of mutant huntingtin (mhtt-exon1) in discrete neuronal populations. We show that mhtt aggregation is a cell-autonomous process. However, progressive motor deficits and cortical neuropathology are only observed when mhtt expression is in multiple neuronal types, including cortical interneurons, but not when mhtt expression is restricted to cortical pyramidal neurons. We further demonstrate an early deficit in cortical inhibition, suggesting that pathological interactions between interneurons and pyramidal neurons may contribute to the cortical manifestation of HD. Our study provides genetic evidence that pathological cell-cell interactions elicited by neuropathogenic forms of mhtt can critically contribute to cortical pathogenesis in a HD mouse model. 相似文献
67.
Cell-to-cell movement of the CAPRICE protein in Arabidopsis root epidermal cell differentiation 总被引:5,自引:0,他引:5
Kurata T Ishida T Kawabata-Awai C Noguchi M Hattori S Sano R Nagasaka R Tominaga R Koshino-Kimura Y Kato T Sato S Tabata S Okada K Wada T 《Development (Cambridge, England)》2005,132(24):5387-5398
CAPRICE (CPC), a small, R3-type Myb-like protein, is a positive regulator of root hair development in Arabidopsis. Cell-to-cell movement of CPC is important for the differentiation of epidermal cells into trichoblasts (root hair cells). CPC is transported from atrichoblasts (hairless cells), where it is expressed, to trichoblasts, and generally accumulates in their nuclei. Using truncated versions of CPC fused to GFP, we identified a signal domain that is necessary and sufficient for CPC cell-to-cell movement. This domain includes the N-terminal region and a part of the Myb domain. Amino acid substitution experiments indicated that W76 and M78 in the Myb domain are critical for targeted transport, and that W76 is crucial for the nuclear accumulation of CPC:GFP. To evaluate the tissue-specificity of CPC movement, CPC:GFP was expressed in the stele using the SHR promoter and in trichoblasts using the EGL3 promoter. CPC:GFP was able to move from trichoblasts to atrichoblasts but could not exit from the stele, suggesting the involvement of tissue-specific regulatory factors in the intercellular movement of CPC. Analyses with a secretion inhibitor, Brefeldin A, and with an rhd3 mutant defective in the secretion process in root epidermis suggested that intercellular CPC movement is mediated through plasmodesmata. Furthermore, the fusion of CPC to tandem-GFPs defined the capability of CPC to increase the size exclusion limit of plasmodesmata. 相似文献
68.
Takuji?Noma Michael?J.?BrewerEmail author Keith?S.?Pike Stephen?D.?Gaimari 《BioControl》2005,50(1):97-111
Parasitoids and predatory flies were sampled in the wheat production region of the west-central Great Plains (southeastern Wyoming, western Nebraska, and north-central Colorado) of North America using plant material infested with the Russian wheat aphid, Diuraphis noxia (Mordvilko) (Hemiptera: Aphididae). Samples were taken April through October in 2001 and 2002, which was 15–16 years after first detection of D. noxia and 5–6 years after the last release of natural enemies for its control in this region. The natural enemies detected were (in order of high to low detection frequencies across three states and 2 years): Aphelinus albipodus Hayat and Fatima (Hymenoptera: Aphelinidae), Eupeodes volucris Osten Sacken (Diptera: Syrphidae), Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae, Aphidiinae), Leucopis gaimarii Tanasijtshuk (Diptera: Chamaemyiidae), Aphidius avenaphis (Fitch), Aphidius matricariae Haliday, Diaeretiella rapae (MIntosh), Aphidius ervi Haliday, Praon yakimanum Pike and Starý (Hymenoptera: Braconidae, Aphidiinae), and Aphelinus asychis Walker (Hymenoptera: Aphelinidae). The results confirmed establishment of one of the 10 exotic parasitoid species released for D. noxia control (A. albipodus) in the west-central Great Plains. It is unknown whether detection of A. asychis, A. matricariae, and D. rapae can be attributed to exotic introductions or preexisting populations. Other species detected in this study have been previously documented from the western US, although the recognized distributions have expanded for A. avenaphis, L. gaimarii, and P. yakimanum compared to the first few years after initial detection of D. noxia. Thus, there is definitive establishment of one exotic introduced for D. noxia and considerable range expansion of preexisting species that prey upon D. noxia. 相似文献
69.
Cheng CH Chung MC Liu SM Chen SK Kao FY Lin SJ Hsiao SH Tseng IC Hsing YI Wu HP Chen CS Shaw JF Wu J Matsumoto T Sasaki T Chen HH Chow TY 《Molecular genetics and genomics : MGG》2005,274(4):337-345
A fine physical map of the rice (Oryza sativa spp. Japonica var. Nipponbare) chromosome 5 with bacterial artificial chromosome (BAC) and PI-derived artificial chromosome (PAC) clones
was constructed through integration of 280 sequenced BAC/PAC clones and 232 sequence tagged site/expressed sequence tag markers
with the use of fingerprinted contig data of the Nipponbare genome. This map consists of five contigs covering 99% of the
estimated chromosome size (30.08 Mb). The four physical gaps were estimated at 30 and 20 kb for gaps 1–3 and gap 4, respectively.
We have submitted 42.2-Mb sequences with 29.8 Mb of nonoverlapping sequences to public databases. BAC clones corresponding
to telomere and centromere regions were confirmed by BAC-fluorescence in situ hybridization (FISH) on a pachytene chromosome.
The genetically centromeric region at 54.6 cM was covered by a minimum tiling path spanning 2.1 Mb with no physical gaps.
The precise position of the centromere was revealed by using three overlapping BAC/PACs for ~150 kb. In addition, FISH results
revealed uneven chromatin condensation around the centromeric region at the pachytene stage. This map is of use for positional
cloning and further characterization of the rice functional genomics.
Electronic supplementary material Supplementary material is available in the online version of this article at
and is accessible for authorized users.
Chia-Hsiung Cheng and Mei-Chu Chung have equal contributions. 相似文献
70.
Kuramoto T Uzuyama H Hatakeyama T Tamura T Nakashima T Yamaguchi K Oda T 《Journal of biochemistry》2005,137(1):41-50
We found that CEL-I was a potent cytotoxic lectin. MDCK, HeLa, and XC cells were highly sensitive to CEL-I cytotoxicity and killed in a dose-dependent manner, whereas CHO, L929, and RAW264.7 cells were relatively resistant to CEL-I, and no significant toxicity was observed up to 10 microg/ml. Among these cell lines, MDCK cells showed the highest susceptibility to CEL-I cytotoxicity. A binding study using FITC-labeled CEL-I (F-CEL-I) revealed that the amounts of bound F-CEL-I on the sensitive cell lines were evidently greater than those on the resistant cell lines, suggesting that the different susceptibility of the cell lines to CEL-I cytotoxicity is partly explained by different efficiencies of binding of CEL-I to these cell lines. Interestingly, the cytotoxicity of CEL-I toward MDCK cells was more potent than those of other lectins such as WGA, PHA-L, and Con A, even though these lectins were capable of binding to MDCK cells at comparable levels to CEL-I. Since the cytotoxicity of CEL-I was strongly inhibited by GalNAc, the binding to cell surface specific carbohydrates is essential for the CEL-I cytotoxicity. The trypan blue dye exclusion test indicated that CEL-I caused a disorder of plasma membrane integrity as a relatively early event. CEL-I failed to induce the release of carboxyfluorescein (CF) from CF-loaded MDCK cells as seen for pore-forming hemolytic isolectin CEL-III, suggesting that the primary cellular target of CEL-I may be the plasma membrane, but its action mechanism differs from that of CEL-III. Although CEL-I induced dramatic cellular morphological changes in MDCK cells, neither typical apoptotic nuclear morphological changes nor DNA fragmentation was observed in CEL-I-treated MDCK cells even after such cellular changes. Our results demonstrated that CEL-I showed a potent cytotoxic effect, especially on MDCK cells, by causing plasma membrane disorder without induction of apoptosis. 相似文献