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81.
Interactions between cells and between tissues are importantin the development and morphogenesis of higher plants. Attemptsto characterize the role of the cell wall in such interactionshave benefited from the use of carrot (Daucus carota L.) culturedcells in vitro as a model system. The development of carrotcells in culture can be divided into three processes: the acquisitionof embryogenic competence; the development of the embryo; andthe maturation and dormancy of the embryo. Induction of non-embryogeniccallus is accompanied by weakened intercellular attachment,decreased levels of endogenous ABA and a decrease in responsivenessto exogenous ABA. Cell wall polysaccharides are known to beinvolved in various developmental and morphogenetic events.In carrot cultured cells, possible roles in intercellular attachmenthave been proposed for arabinan and xylose in the neutral sugarregions of pectins, and various extracellular proteins havebeen shown to be involved in somatic embryogenesis in vitro.Some of these proteins are also present around and/or in zygoticembryos, possibly being involved in the formation and functionsof zygotic embryos and seeds. A 57-kDa extracellular solubleglycoprotein that binds to insulin-like peptides and an 18-kDaextracellular insoluble cystatin that inhibits the proteinasesof germinating seeds of carrot might be involved in cellularsignal transduction and inter-tissue interaction, respectively,in carrot seeds.
1 Recipient of the JSPP Young Investigator Award, 1997 相似文献
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Seiji Iwama Masaki Segawa Shinobu Fujii Kiyoshi Ikeda Shigeo Katsumura 《Bioorganic & medicinal chemistry letters》1998,8(24):781-3498
All stereoisomers of N-acyl-4,5-disubstituted oxazolidinone phospholipid analogs were synthesized by regio and stereoselective epoxide ring opening accompanied by introduction of an amino group. The (4R,5S)-derivative showed stronger inhibitory activity toward type II phospholipase A2 than the 4-substituted oxazolidinone phospholipid analog previously reported. 相似文献
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Shiho Hayakawa Yasuharu Takaku Jung Shan Hwang Takeo Horiguchi Hiroshi Suga Walter Gehring Kazuho Ikeo Takashi Gojobori 《PloS one》2015,10(3)
The ocelloid is an extraordinary eyespot organelle found only in the dinoflagellate family Warnowiaceae. It contains retina- and lens-like structures called the retinal body and the hyalosome. The ocelloid has been an evolutionary enigma because of its remarkable resemblance to the multicellular camera-type eye. To determine if the ocelloid is functionally photoreceptive, we investigated the warnowiid dinoflagellate Erythropsidinium. Here, we show that the morphology of the retinal body changed depending on different illumination conditions and the hyalosome manifests the refractile nature. Identifying a rhodopsin gene fragment in Erythropsidinium ESTs that is expressed in the retinal body by in situ hybridization, we also show that ocelloids are actually light sensitive photoreceptors. The rhodopsin gene identified is most closely related to bacterial rhodopsins. Taken together, we suggest that the ocelloid is an intracellular camera-type eye, which might be originated from endosymbiotic origin. 相似文献
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Yayoi Sato Hiromitsu Hara Toshiaki Okuno Naoko Ozaki Shinobu Suzuki Takehiko Yokomizo Tsuneyasu Kaisho Hiroki Yoshida 《Biochemical and biophysical research communications》2014
IL-27 is a heterodimeric cytokine that regulates both innate and adaptive immunity. The immunosuppressive effect of IL-27 largely depends on induction of IL-10-producing Tr1 cells. To date, however, effects of IL-27 on regulation of immune responses via mediators other than cytokines remain poorly understood. To address this issue, we examined immunoregulatory effects of conditional medium of bone marrow-derived macrophages (BMDMs) from WSX-1 (IL-27Rα)-deficient mice and found enhanced IFN-γ and IL-17A secretion by CD4+ T cells as compared with that of control BMDMs. We then found that PGE2 production and COX-2 expression by BMDMs from WSX-1-deficient mice was increased compared to control macrophages in response to LPS. The enhanced production of IFN-γ and IL-17A was abolished by EP2 and EP4 antagonists, demonstrating PGE2 was responsible for enhanced cytokine production. Murine WSX-1-expressing Raw264.7 cells (mWSX-1-Raw264.7) showed phosphorylation of both STAT1 and STAT3 in response to IL-27 and produced less amounts of PGE2 and COX-2 compared to parental RAW264.7 cells. STAT1 knockdown in parental RAW264.7 cells and STAT1-deficiency in BMDMs showed higher COX-2 expression than their respective control cells. Collectively, our result indicated that IL-27/WSX-1 regulated PGE2 secretion via STAT1–COX-2 pathway in macrophages and affected helper T cell response in a PGE2-mediated fashion. 相似文献
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Masanori A. Murayama Shigeru Kakuta Takumi Maruhashi Kenji Shimizu Akimasa Seno Sachiko Kubo Nozomi Sato Shinobu Saijo Masahira Hattori Yoichiro Iwakura 《Biochemical and biophysical research communications》2014
Rheumatoid arthritis (RA) is an autoimmune inflammatory disease exhibited most commonly in joints. We found that the expression of C1qtnf3, which encodes C1q/TNF-related protein 3 (CTRP3), was highly increased in two mouse RA models with different etiology. To elucidate the pathogenic roles of CTRP3 in the development of arthritis, we generated C1qtnf3−/− mice and examined the development of collagen-induced arthritis in these mice. We found that the incidence and severity score was higher in C1qtnf3−/− mice compared with wild-type (WT) mice. Histopathology of the joints was also more severe in C1qtnf3−/− mice. The levels of antibodies against type II collagen and pro-inflammatory cytokine mRNAs in C1qtnf3−/− mice were higher than WT mice. These observations indicate that CTRP3 plays an important role in the development of autoimmune arthritis, suggesting CTRP3 as a possible medicine to treat RA. 相似文献
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Development of Multiplex PCR to Detect Five Pythium Species Related to Turfgrass Diseases 总被引:1,自引:0,他引:1
Takahiro Asano Masako Senda Haruhisa Suga Koji Kageyama 《Journal of Phytopathology》2010,158(9):609-615
The objective of this study was to develop multiplex PCR detection method for five Pythium species associated with turfgrass diseases, Pythium aphanidermatum, Pythium arrhenomanes, Pythium graminicola, Pythium torulosum and Pythium vanterpoolii. Species‐specific primers and two common primers were designed based on the sequences of the internal transcribed spacer region of ribosomal DNA. Another primer set by which all organisms would be amplified in 18S rDNA was used as a positive control. When these total nine primers were applied to the multiplex PCR, all species were individually discriminated in the mixture of five species culture DNA. Furthermore, all five Pythium species were detected in naturally infected plants using the multiplex PCR. 相似文献
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