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61.
Yoshio Ogawa Atsuhiro Suda Kuniko Kusama-Eguchi Kazuko Watanabe Seiji Tokumasu 《Mycoscience》2005,46(6):343-351
Umbelopsis ramanniana is a well-known species in this genus. A characteristic morphological feature of this fungus is the remarkable variation
in the sporangiospore shape, which implies the genetic variations occur in the nucleotide sequences of the internal transcribed
spacer (ITS) regions of the nuclear ribosomal DNA (nrDNA) in the U. ramanniana isolates. The relationship between the variations of the sequences of the nrDNA ITS regions and those of the sporangiospore
morphology was investigated for 12 isolates of U. ramanniana collected in Europe. Neighbor-joining and parsimony analyses on the sequences suggested that these isolates split into three
groups. Precise examination of the morphology showed that the isolates of those respective groups were different from each
other in their sporangiospore shape. The present study implies at least three intraspecific groups exist in U. ramanniana and that the variations in the nucleotide sequences of the nrDNA ITS regions correlate well with those in the sporangiospore
shape in these intraspecific groups. 相似文献
62.
Toshiro Nishimura Shigekazu Teranishi Atsuhiro Kawashima Tadashi Ishimaru Takaki Miwa Mitsuru Furukawa 《Chemical senses》2002,27(1):13-21
Systemic or topical application of glucocorticoid is the treatment of choice for olfactory disturbance. Recently, Na(+)/K(+) ATPase and glucocorticoid receptor immunoreactivity in the olfactory mucosa was reported. To elucidate a glucocorticoid action on Na(+)/K(+) ATPase production, an animal model was produced by an intra-nasal application of 5% ZnSO(4) solution to Wistar rats. Dexamethasone was injected i.p. (0.01 mg/100 g) for 14 days after the insult. Histologically, the regeneration process was completed on day 14 in both dexamethasone- and saline-injected control rats. We used a quantitative polymerase chain reaction (PCR) method to evaluate mRNA production of Na(+)/K(+) ATPase and glucocorticoid receptor. In dexamethasone-injected rats, up-regulation of glucocorticoid receptor mRNA (95% more than control rats, P = 0.00068, unpaired t-test) and of Na(+)/K(+) ATPase mRNA expression (76% more than control rats, P = 0.0042) was observed on day 14. The increased Na(+)/K(+) ATPase expression in the regenerated olfactory mucosa is thought to be beneficial for an active uptake of K(+), which is released during excitation, around olfactory neurons and for the transepithelial absorption of Na(+) from olfactory mucus. Dexamethasone may thus contribute to the recovery of function after the morphological regeneration in part, at least, through its receptor by regulation of the ionic concentration in the olfactory mucosal microenvironment. 相似文献
63.
Atsuhiro Matsumoto Takanori Kanai Yohei Mikami Po–Sung Chu Nobuhiro Nakamoto Hirotoshi Ebinuma Hidetsugu Saito Toshiro Sato Hideo Yagita Toshifumi Hibi 《PloS one》2013,8(4)
Retinoid-related orphan receptor (ROR) γt is known to be related to the development and function of various immunological compartments in the liver, such as Th17 cells, natural killer T (NKT) cells, and innate lymphoid cells (ILCs). We evaluated the roles of RORγt-expressing cells in mouse acute hepatitis model using RORγt deficient (RORγt−/−) mice and RAG-2 and RORγt double deficient (RAG-2−/− × RORγt−/−) mice. Acute hepatitis was induced in mice by injection with carbon tetrachloride (CCl4), to investigate the regulation of liver inflammation by RORγt-expressing cells. We detected RORC expression in three compartments, CD4+ T cells, NKT cells, and lineage marker-negative SCA-1+Thy1high ILCs, of the liver of wild type (WT) mice. CCl4-treated RORγt−/− mice developed liver damage in spite of lack of RORγt-dependent cells, but with reduced infiltration of macrophages compared with WT mice. In this regard, ILCs were significantly decreased in RAG-2−/− × RORγt−/− mice that lacked T and NKT cells. Surprisingly, RAG-2−/− × RORγt−/− mice developed significantly severer CCl4-induced hepatitis compared with RAG-2−/− mice, in accordance with the fact that hepatic ILCs failed to produce IL-22. Lastly, anti-Thy1 monoclonal antibody (mAb), but not anti-NK1.1 mAb or anti-asialo GM1 Ab administration exacerbated liver damage in RAG-2−/− mice with the depletion of liver ILCs. Collectively, hepatic RORγt-dependent ILCs play a part of protective roles in hepatic immune response in mice. 相似文献
64.
Qualitative differences in chromatins of adult tissues demonstrated by action of DNase 总被引:1,自引:0,他引:1
H Namiki 《Biochemical and biophysical research communications》1973,50(3):662-669
Treatment of chromatin from rat or mouse tissues with DNase rendered it tissue-specific in subsequent hybridization with H3-labeled RNA's. It hybridized least with RNA from the same organ and most efficiently with RNA's from completely different organs. DNase-residual DNA's of forebrain were sufficiently specific to distinguish in this way between RNA's from different parts of the brain. 相似文献
65.
Naoki Tokuhara Kana Namiki Mai Uesugi Chihiro Miyamoto Makoto Ohgoh Katsutoshi Ido Takashi Yoshinaga Toshihiko Yamauchi Junro Kuromitsu Sadao Kimura Norimasa Miyamoto Yoshitoshi Kasuya 《The Journal of biological chemistry》2010,285(43):33294-33306
One of the family of voltage-gated calcium channels (VGCC), the N-type Ca2+ channel, is located predominantly in neurons and is associated with a variety of neuronal responses, including neurodegeneration. A precise mechanism for how the N-type Ca2+ channel plays a role in neurodegenerative disease, however, is unknown. In this study, we immunized N-type Ca2+ channel α1B-deficient (α1B−/−) mice and their wild type (WT) littermates with myelin oligodendrocyte glycoprotein 35–55 and analyzed the progression of experimental autoimmune encephalomyelitis (EAE). The neurological symptoms of EAE in the α1B−/− mice were less severe than in the WT mice. In conjunction with these results, sections of the spinal cord (SC) from α1B−/− mice revealed a reduction in both leukocytic infiltration and demyelination compared with WT mice. No differences were observed in the delayed-type hypersensitivity response, spleen cell proliferation, or cytokine production from splenocytes between the two genotypes. On the other hand, Western blot array analysis and RT-PCR revealed that a typical increase in the expression of MCP-1 in the SC showed a good correlation with the infiltration of leukocytes into the SC. Likewise, immunohistochemical analysis showed that the predominant source of MCP-1 was activated microglia. The cytokine-induced production of MCP-1 in primary cultured microglia from WT mice was significantly higher than that from α1B−/− mice and was significantly inhibited by a selective N-type Ca2+ channel antagonist, ω-conotoxin GVIA or a withdrawal of extracellular Ca2+. These results suggest that the N-type Ca2+ channel is involved in the pathogenesis of EAE at least in part by regulating MCP-1 production by microglia. 相似文献
66.
Takachika Hiroi Kazuo Fukushima Ikuo Kantake Yuji Namiki Tadashi Ikeda 《FEMS microbiology letters》1992,96(2-3):193-198
Adherence of 3H-labelled cells of Streptococcus gordonii and Streptococcus milleri to artificial pellicles prepared from saliva supplemented with glucosyltransferases from mutants streptococci was examined using a new assay for sucrose-dependent cell-to-pellicle attachment. Results indicate that S. gordonii, but not S. milleri, could attach tightly to hydroxylapatite surfaces through de novo glucan synthesis by mutants streptococcal glucosyltransferases present in the experimental salivary pellicles. 相似文献
67.
Complex structure of cytochrome c–cytochrome c oxidase reveals a novel protein–protein interaction mode 下载免费PDF全文
Satoru Shimada Kyoko Shinzawa‐Itoh Junpei Baba Shimpei Aoe Atsuhiro Shimada Eiki Yamashita Jiyoung Kang Masaru Tateno Shinya Yoshikawa Tomitake Tsukihara 《The EMBO journal》2017,36(3):291-300
Mitochondrial cytochrome c oxidase (CcO) transfers electrons from cytochrome c (Cyt.c) to O2 to generate H2O, a process coupled to proton pumping. To elucidate the mechanism of electron transfer, we determined the structure of the mammalian Cyt.c–CcO complex at 2.0‐Å resolution and identified an electron transfer pathway from Cyt.c to CcO. The specific interaction between Cyt.c and CcO is stabilized by a few electrostatic interactions between side chains within a small contact surface area. Between the two proteins are three water layers with a long inter‐molecular span, one of which lies between the other two layers without significant direct interaction with either protein. Cyt.c undergoes large structural fluctuations, using the interacting regions with CcO as a fulcrum. These features of the protein–protein interaction at the docking interface represent the first known example of a new class of protein–protein interaction, which we term “soft and specific”. This interaction is likely to contribute to the rapid association/dissociation of the Cyt.c–CcO complex, which facilitates the sequential supply of four electrons for the O2 reduction reaction. 相似文献
68.
Nemoto K Hara M Goto S Kasai K Seki H Suzuki M Oka A Muranaka T Mano Y 《Journal of plant physiology》2009,166(7):729-738
Tobacco (Nicotiana tabacum) Bright Yellow-2 (BY-2) cells are rapidly proliferating meristematic cells that require auxin for culture in vitro. We have established several transgenic BY-2 cell lines that carry the T-DNA of Agrobacterium rhizogenes 15834, which harbors an agropine-type root-inducing (Ri) plasmid. Two of these lines, BYHR-3 and BYHR-7, were used to test the role of auxin in the proliferation of plant cells. The lines grew rapidly in Linsmaier-Skoog (LS) medium lacking auxin and other phytohormones. The TR-DNA, containing the aux1 (tryptophan monooxygenase) and aux2 (indoleacetamide hydrolase) genes, was present in the genomes of both transgenic lines, whereas the TL-DNA, containing the rolA, B, C and D genes, was present in the genome of BYHR-7 but not BYHR-3. Since the introduction of the rolABCD genes alone did not affect the auxin requirement of BY-2 cells, the aux1 and aux2 genes, but not the rolABCD genes, appear to be relevant to the auxin autotrophy of these transgenic lines. Furthermore, the overexpression of aux1 allowed BY-2 cells to grow rapidly in the absence of auxin, suggesting the existence in plant cells of an unidentified gene whose product is functionally equivalent or similar to that of aux2 of the Ri plasmid. 相似文献
69.
OsFRDL1 Is a Citrate Transporter Required for Efficient Translocation of Iron in Rice 总被引:6,自引:0,他引:6
Kengo Yokosho Naoki Yamaji Daisei Ueno Namiki Mitani Jian Feng Ma 《Plant physiology》2009,149(1):297-305
Multidrug and toxic compound extrusion (MATE) transporters represent a large family in plants, but their functions are poorly understood. Here, we report the function of a rice (Oryza sativa) MATE gene (Os03g0216700, OsFRDL1), the closest homolog of barley (Hordeum vulgare) HvAACT1 (aluminum [Al]-activated citrate transporter 1), in terms of metal stress (iron [Fe] deficiency and Al toxicity). This gene was mainly expressed in the roots and the expression level was not affected by either Fe deficiency or Al toxicity. Knockout of this gene resulted in leaf chlorosis, lower leaf Fe concentration, higher accumulation of zinc and manganese concentration in the leaves, and precipitation of Fe in the root's stele. The concentration of citrate and ferric iron in the xylem sap was lower in the knockout line compared to the wild-type rice. Heterologous expression of OsFRDL1 in Xenopus oocytes showed transport activity for citrate. Immunostaining showed that OsFRDL1 was localized at the pericycle cells of the roots. On the other hand, there was no difference in the Al-induced secretion of citrate from the roots between the knockout line and the wild-type rice. Taken together, our results indicate that OsFRDL1 is a citrate transporter localized at the pericycle cells, which is necessary for efficient translocation of Fe to the shoot as a Fe-citrate complex. 相似文献
70.
HvLsi1 is a silicon influx transporter in barley 总被引:1,自引:0,他引:1
Chiba Y Mitani N Yamaji N Ma JF 《The Plant journal : for cell and molecular biology》2009,57(5):810-818
Most plants accumulate silicon in their bodies, and this is thought to be important for resistance against biotic and abiotic stresses; however, the molecular mechanisms for Si uptake and accumulation are poorly understood. Here, we describe an Si influx transporter, HvLsi1, in barley. This protein is homologous to rice influx transporter OsLsi1 with 81% identity, and belongs to a Nod26-like major intrinsic protein sub-family of aquaporins. Heterologous expression in both Xenopus laevis oocytes and a rice mutant defective in Si uptake showed that HvLsi1 has transport activity for silicic acid. Expression of HvLsi1 was detected specifically in the basal root, and the expression level was not affected by Si supply. There was a weak correlation between Si uptake and the expression level of HvLsi1 in eight cultivars tested. In the seminal roots, HvLsi1 is localized on the plasma membrane on the distal side of epidermal and cortical cells. HvLsi1 is also located in lateral roots on the plasma membrane of hypodermal cells. These cell-type specificity of localization and expression patterns of HvLsi1 are different from those of OsLsi1. These observations indicate that HvLsi1 is a silicon influx transporter that is involved in radial transport of Si through the epidermal and cortical layers of the basal roots of barley. 相似文献