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81.
Yuji Suehiro Teruhiro Okuyama Kiyoshi Naruse Takeo Kubo Hideaki Takeuchi 《FEBS letters》2010,584(16):3545-201
In this study, we demonstrated that human type-5 adenovirus infected the brain of the teleost fish, medaka (Oryzias latipes), in vivo. Injection of adenoviral vector into the mesencephalic ventricle of medaka larvae induced the expression of reporter genes in some parts of the telencephalon, the periventricular area of the mesencephalon and diencephalon, and the cerebellum. Additionally, the Cre-loxP system works in medaka brains using transgenic medaka carrying a vector containing DsRed2, flanked by loxP sites under control of the β-actin promoter and downstream promoterless enhanced green fluorescent protein (EGFP). We demonstrated that the presence of green fluorescence depended on injection of adenoviral vector expressing the Cre gene and confirmed that EGFP mRNA was transcribed in the virus-injected larvae. 相似文献
82.
Shingo Izawa Kayo Ikeda Takeo Miki Yoshinori Wakai Yoshiharu Inoue 《Applied microbiology and biotechnology》2010,88(1):277-282
Although ethanol and osmotic stress affect the vacuolar morphology of Saccharomyces cerevisiae, little information is available about changes in vacuolar morphology during the processes of wine making and Japanese sake (rice wine) brewing. Here, we elucidated changes in the morphology of yeast vacuoles using Zrc1p-GFP, a vacuolar membrane
protein, so as to better understand yeast physiology during the brewing process. Wine yeast cells (OC-2 and EC1118) contained
highly fragmented vacuoles in the sake mash (moromi) as well as in the grape must. Although sake yeast cells (Kyokai no. 9 and no. 10) also contained highly fragmented vacuoles during the wine-making process, they showed quite a distinct
vacuolar morphology during sake brewing. Since the environment surrounding sake yeast cells in the sake mash did not differ much from that surrounding wine yeast cells, the difference in vacuolar morphology during sake brewing between wine yeast and sake yeast was likely caused by innate characters. 相似文献
83.
Mitsue Shibata Satoshi Kikuchi Hiroshi Tanaka Masahiro Sueyoshi Hiroshi Yoshimaru Kaoru Niiyama 《Ecological Research》2009,24(1):1-9
The effects of local population density, sex morph [protogynous (PG) or protandrous (PA)], and individual tree size on the
demographic processes of seed production were investigated in a heterodichogamous maple, Acer mono Maxim. var. Marmoratum (Nichols.) Hara f. dissectum, in a temperate forest of Japan. As the distance from conspecific reproductive adults increased, the percentage of immature
seed fall and empty seeds increased significantly, indicating higher pollination success along with local population density.
Although the difference was not distinct, pollination success was affected by the local population density of the reciprocal
sex morph rather than that of both sex morphs. The trees at higher local population density sites suffered higher seed mortality
due to predation and decay, and tended to produce smaller seeds. Thus, the impacts of local population density operated both
positively and negatively on reproduction. As a factor of individual traits, tree size scarcely affected any demographic processes.
On the other hand, sex morph did affect pollination success. Trees of PG type had lower immature seed fall than those of PA
type, suggesting that the former has higher efficiency of pollen acceptance than the latter. The results on seed demography
presented here partly support previous suggestions that heterodichogamous plants exhibit reciprocal cross-pollination and
gender specialization as reproductive traits. 相似文献
84.
85.
Fumiyuki Nakagawa Katsutaro Morino Satoshi Ugi Atsushi Ishikado Keiko Kondo Daisuke Sato Shiho Konno Ken-ichi Nemoto Chisato Kusunoki Osamu Sekine Akihiro Sunagawa Masanori Kawamura Noriko Inoue Yoshihiko Nishio Hiroshi Maegawa 《Biochemical and biophysical research communications》2014
It has recently been reported that expression of heme oxygenase-1 (HO-1) plays a protective role against many diseases. Furthermore, n-3 polyunsaturated fatty acids (PUFAs) were shown to induce HO-1 expression in several cells in vitro, and in a few cases also in vivo. However, very few reports have demonstrated that n-3 PUFAs induce HO-1 in vivo. 相似文献
86.
The industrial yeast Candida utilis can grow on media containing xylose as sole carbon source, but cannot ferment it to ethanol. The deficiency might be due to the low activity of NADPH-preferring xylose reductase (XR) and NAD(+)-dependent xylitol dehydogenase (XDH), which convert xylose to xylulose, because C. utilis can ferment xylulose. We introduced multiple site-directed mutations in the coenzyme binding sites of XR and XDH derived from the xylose-fermenting yeast Candida shehatae to alter their coenzyme specificities. Several combinations of recombinant and native XRs and XDHs were tested. Highest productivity was observed in a strain expressing CsheXR K275R/N277D (NADH-preferring) and native CsheXDH (NAD(+)-dependent), which produced 17.4 g/L of ethanol from 50 g/L of xylose in 20 h. Analysis of the genes responsible for ethanol production from the xylose capacity of C. utilis indicated that the introduction of CsheXDH was essential, while overexpression of CsheXR K275R/N277D improved efficiency of ethanol production. 相似文献
87.
Wang X Morales AR Urakami T Zhang L Bondar MV Komatsu M Belfield KD 《Bioconjugate chemistry》2011,22(7):1438-1450
A two-photon absorbing (2PA) and aggregation-enhanced near-infrared (NIR) emitting pyran derivative, encapsulated in and stabilized by silica nanoparticles (SiNPs), is reported as a nanoprobe for two-photon fluorescence microscopy (2PFM) bioimaging that overcomes the fluorescence quenching associated with high chromophore loading. The new SiNP probe exhibited aggregate-enhanced emission producing nearly twice as strong a signal as the unaggregated dye, a 3-fold increase in two-photon absorption relative to the DFP in solution, and approximately 4-fold increase in photostability. The surface of the nanoparticles was functionalized with a folic acid (FA) derivative for folate-mediated delivery of the nanoprobe for 2PFM bioimaging. Surface modification of SiNPs with the FA derivative was supported by zeta potential variation and (1)H NMR spectral characterization of the SiNPs as a function of surface modification. In vitro studies using HeLa cells expressing a folate receptor (FR) indicated specific cellular uptake of the functionalized nanoparticles. The nanoprobe was demonstrated for FR-targeted one-photon in vivo imaging of HeLa tumor xenograft in mice upon intravenous injection of the probe. The FR-targeting nanoprobe not only exhibited highly selective tumor targeting but also readily extravasated from tumor vessels, penetrated into the tumor parenchyma, and was internalized by the tumor cells. Two-photon fluorescence microscopy bioimaging provided three-dimensional (3D) cellular-level resolution imaging up to 350 μm deep in the HeLa tumor. 相似文献
88.
OsWRKY28, a PAMP-responsive transrepressor, negatively regulates innate immune responses in rice against rice blast fungus 总被引:1,自引:0,他引:1
89.
Satoshi Oguchi Hiroyuki Saito Masayoshi Tsukahara Haruhiko Tsumura 《Cytotechnology》2006,52(3):199-207
Controlling cell proliferation during cell culturing is an effective way to improve the production yield in mammalian cell
culture. We examined the effect of temperature shifts (TS) under pH control conditions in Chinese hamster ovary cells. When
we shifted the culture temperature from 37 °C to 31 °C before a stationary phase at pH 6.8 (TS/pH 6.8), cell viability remained
high, and the final human monoclonal antibody (hMab) concentration increased to 2.3 times that in the culture remaining at
37 °C. However, there were no significant effects on the cell viability or production yield with the same TS at pH 7.0 (TS/pH
7.0). The average specific hMab productivity and mRNA level of TS/pH 7.0 were the same as that of TS/pH 6.8. The control of
cell growth by the TS or the addition of rapamycin was effective in the maintenance of cell viability, but there was no significant
increase of the average specific hMab productivity in the culture where cell proliferation was controlled with rapamycin.
The hMab mRNA concentration decreased to 55%–65% at a 37 °C culture with the addition of actinomycin D. In contrast, actinomycin
D did not affect the mRNA level in the TS culture. This result suggested that the increase in the mRNA level in the TS condition
was caused by an increase in mRNA stability. In this study, we show that TS can produce two unrelated effects: a prolongation
of cell longevity and an improvement in mRNA stability. 相似文献
90.
nanos1: a mouse nanos gene expressed in the central nervous system is dispensable for normal development 总被引:2,自引:0,他引:2
Haraguchi S Tsuda M Kitajima S Sasaoka Y Nomura-Kitabayashid A Kurokawa K Saga Y 《Mechanisms of development》2003,120(6):721-731
A mouse nanos (nanos1) gene was cloned and its function was examined by generating a gene-knockout mouse. The nanos1 gene encodes an RNA-binding protein, which contains a putative zinc-finger motif that exhibits similarity with other nanos-class genes in vertebrates and invertebrates. Although nanos1 is not detected in primordial germ cells, it is observed in seminiferous tubules of mature testis. Interestingly, maternally expressed nanos1 is observed in substantial amounts in oocytes, but the amount of maternal RNA is rapidly reduced after fertilization, and the transient zygotic nanos1 expression is observed in eight-cell embryos. At 12.5 days postcoitum, nanos1 is re-expressed in the central nervous system and the expression continues in the adult brain, in which the hippocampal formation is the predominant region. The nanos1 -deficient mice develop to term without any detectable abnormality and they are fertile. No significant neural defect is observed in terms of their behavior to date. 相似文献