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161.
162.
Molecular Characterization and Heterologous Expression of the Gene Encoding a Low-Molecular-Mass Endoglucanase from Trichoderma reesei QM9414 总被引:3,自引:0,他引:3
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163.
Production of Reactive Oxygen Species and Release of l-Glutamate During Superoxide Anion-Induced Cell Death of Cerebellar Granule Neurons 总被引:3,自引:0,他引:3
Takumi Satoh Tadahiro Numakawa Yasuhiro Abiru Tomoko Yamagata Yasuyuki Ishikawa Yasushi Enokido Hiroshi Hatanaka 《Journal of neurochemistry》1998,70(1):316-324
Abstract: Enhanced production of superoxide anion (O2 − ) is considered to play a pivotal role in the pathogenesis of CNS neurons. Here, we report that O2 − generated by xanthine (XA) + xanthine oxidase (XO) triggered cell death associated with nuclear condensation and DNA fragmentation in cerebellar granule neuron. XA + XO induced significant increases in amounts of intracellular reactive oxygen species (ROS) before initiating loss of cell viability, as determined by measurement of 6-carboxy-2',7'-dichlorodihydrofluorescein diacetate, di(acetoxymethyl ester) (C-DCDHF-DA) for O2 − and other ROS and hydroethidine (HEt) specifically for O2 − by using fluorescence microscopy and flow cytometry. Catalase, but not superoxide dismutase (SOD), significantly protected granule neurons from the XA + XO-induced cell death. Catalase effectively reduced C-DCDHF-DA but not HEt fluorescence, whereas SOD reduced HEt but not C-DCDHF-DA fluorescence, indicating that HEt and C-DCDHF-DA fluorescence correlated with O2 − and hydrogen peroxide, respectively. The NMDA antagonist MK-801 prevented the death. XA + XO induced an increase in l -glutamate release from cerebellar granule neurons. These results indicate that elevation of O2 − induces cell death associated with increasing ROS production in cerebellar granule neurons and that XA + XO enhanced release of l -glutamate. 相似文献
164.
Takashi Araki Yasushi Kobayashi Hidetaka Kaya Masaki Iwabuchi 《Journal of plant research》1998,111(2):277-281
Transition from vegetative to reproductive development (flowering) is one of the most important decisions during the post-embryonic
development of flowering plants. More than twenty loci are known to regulate this process inArabidopsis. Some of these flowering-time genes may act at the shoot apical meristem to regulate its competence to respond to floral
inductive signals and floral evocation. Genetic and phenotypic analyses of mutants suggest that the late-flowering geneFT may be a good candidate for such genes. To test this, we have cloned theFT gene using aFT-deficiency line associated with a T-DNA insertion. Cloned genes and loss-of-function mutants in hand, it is now possible
to analyse the role ofFT and other genes in flowering at the biochemical and cellular levels as well as at the genetic level. The deduced FT protein
has homology with TFL1 and CEN proteins believed to be involved in regulation of inflorescence meristem identity. Phylogenetic
analysis suggests that theFT group and theTFL1/CEN group of genes diverged before the diversification of major angiosperm clades. This raises the interesting question of the
evolutionary relationship between the regulation of vegetative/reproductive switching in the shoot apical meristem and the
regulation of inflorescence architecture in angiosperms.
The extended abstract of a paper presented at the 13th International Symposium in Conjugation with Award of the International
Prize for Biology “Fronitier of Plant Biology” 相似文献
165.
Masayuki Mori Shingo Akiyoshi Yosuke Mizuno Hisato Okuizumi Yasushi Okazaki Yoshihide Hayashizaki Masahiko Nishimura 《Mammalian genome》1998,9(9):695-709
We have applied the restriction landmark genomic scanning (RLGS) method to the SMXA recombinant inbred (RI) mouse strain
set to reveal its detailed genetic profile. A total of 663 polymorphic RLGS spot loci were identified, 576 of which were assigned
to chromosomes. Strain distribution patterns (SDPs) at 55 microsatellite marker loci were also obtained. As a result, the
total number of loci with distinct SDPs on chromosomes increased to 400. These loci were dispersed on all chromosomes, except
for the Chromosome (Chr) Y, and effectively covered the genome with an average spacing of 4 cM. The SMXA RI strain set, hereby,
would be of value for genetic study.
Received: 20 February 1998 / Accepted: 19 May 1998 相似文献
166.
Yuichi Sugahara Shingo Akiyoshi Yasushi Okazaki Yoshihide Hayashizaki Isao Tanihata 《Mammalian genome》1998,9(8):643-651
The RLGS (Restriction Landmark Genome Scanning) method was originally developed as a powerful method for enabling viewing
of thousands of restriction landmarks. It offers a tool for obtaining information about genetic loci, with a single RLGS profile
displaying approximately 2000 restriction landmarks as spots. One of the most useful applications is RLGS spot mapping, which
allows the efficient, low-cost construction of the genetic map of any organism. However, analyses of the profiles depend mainly
on human visual observation and are tedious and laborious. Although several commercially available image analyzing systems
for profile comparison have been examined, they cannot be used for the RLGS spot mapping system owing to the background characteristics
of the RLGS profiles, unsatisfactory rates of correspondence, and inefficient correction of informative genetic data. We therefore
developed a novel automatic image analysis system for RLGS spot mapping, using an original algorithm based on the binary image
transferred from the original RLGS profile. This system was employed for identifying non-polymorphic and parental strain-specific
polymorphic spots of the F1 mouse profile and yielded efficient initial screening of RLGS profiles.
Received: 5 December 1997 / Accepted: 6 April 1998 相似文献
167.
Bialek-Bylka Grazyna E. Fujii Ritsuko Chen Chun-Hai Oh-oka Hirozo Kamiesu Akihisa Satoh Kazuhiko Koike Hiroyuki Koyama Yasushi 《Photosynthesis research》1998,58(2):135-142
Carotenoids were extracted, at 4 °C in complete darkness and under nitrogen atmosphere, from the reaction center (RC) of a green-sulfur bacterium and the Photosystem (PS) I RC of a cyanobacterium; each extract was subjected to high-performance liquid chromatography (HPLC) using an apparatus equipped with a two-dimensional diode-array detector in order to spectroscopically identify cis–trans carotenoids while performing HPLC analysis. In the extract from the RC of Chlorobium tepidum, 15-cis and all-trans--carotenes as well as 13-cis-, 15-cis- and all- trans-chlorobactenes (in the order of elution) were identified, whereas in the extract from the PS I RC of Synechococcus vulcanus, 15-cis-, all-trans- and 9-cis--carotenes were found. Thus, the universal presence of 15- cis carotenoids in the 'iron sulfur-type' RCs has been shown in addition to the previous cases of the 'quinone-type' RCs. 相似文献
168.
Ren Matsuba Kensuke Sakai Minako Imamura Yasushi Tanaka Minoru Iwata Hiroshi Hirose Kohei Kaku Hiroshi Maegawa Hirotaka Watada Kazuyuki Tobe Atsunori Kashiwagi Ryuzo Kawamori Shiro Maeda 《PloS one》2015,10(5)
AimWe performed a replication study in a Japanese population to evaluate the association between type 2 diabetes and 7 susceptibility loci originally identified by European genome-wide association study (GWAS) in 2012: ZMIZ1, KLHDC5, TLE1, ANKRD55, CILP2, MC4R, and BCAR1. We also examined the association of 3 additional loci: CCND2 and GIPR, identified in sex-differentiated analyses, and LAMA1, which was shown to be associated with non-obese European type 2 diabetes.MethodsWe genotyped 6,972 Japanese participants (4,280 type 2 diabetes patients and 2,692 controls) for each of the 10 single nucleotide polymorphisms (SNPs): rs12571751 in ZMIZ1, rs10842994 near KLHDC5, rs2796441 near TLE1, rs459193 near ANKRD55, rs10401969 in CILP2, rs12970134 near MC4R, rs7202877 near BCAR1, rs11063069 near CCND2, rs8108269 near GIPR, and rs8090011 in LAMA1 using a multiplex polymerase chain reaction invader assay. The association of each SNP locus with the disease was evaluated using a logistic regression analysis.ResultsAll SNPs examined in this study had the same direction of effect (odds ratio > 1.0, p = 9.77 × 10-4, binomial test), as in the original reports. Among them, rs12571751 in ZMIZ1 was significantly associated with type 2 diabetes [p = 0.0041, odds ratio = 1.123, 95% confidence interval 1.037–1.215, adjusted for sex, age and body mass index (BMI)], but we did not observe significant association of the remaining 9 SNP loci with type 2 diabetes in the present Japanese population (p ≥ 0.005). A genetic risk score, constructed from the sum of risk alleles for the 7 SNP loci identified by un-stratified analyses in the European GWAS meta-analysis were associated with type 2 diabetes in the present Japanese population (p = 2.3 × 10-4, adjusted for sex, age and BMI).ConclusionsZMIZ1 locus has a significant effect on conferring susceptibility to type 2 diabetes also in the Japanese population. 相似文献
169.
Masayuki Morino Kohei Nukina Hiroki Sakaguchi Takeshi Maeda Michiyo Takahara Yasushi Shiomi Hideo Nishitani 《PloS one》2015,10(3)
Cdt1 begins to accumulate in M phase and has a key role in establishing replication licensing at the end of mitosis or in early G1 phase. Treatments that damage the DNA of cells, such as UV irradiation, induce Cdt1 degradation through PCNA-dependent CRL4-Cdt2 ubiquitin ligase. How Cdt1 degradation is linked to cell cycle progression, however, remains unclear. In G1 phase, when licensing is established, UV irradiation leads to Cdt1 degradation, but has little effect on the licensing state. In M phase, however, UV irradiation does not induce Cdt1 degradation. When mitotic UV-irradiated cells were released into G1 phase, Cdt1 was degraded before licensing was established. Thus, these cells exhibited both defective licensing and G1 cell cycle arrest. The frequency of G1 arrest increased in cells expressing extra copies of Cdt2, and thus in cells in which Cdt1 degradation was enhanced, whereas the frequency of G1 arrest was reduced in cell expressing an extra copy of Cdt1. The G1 arrest response of cells irradiated in mitosis was important for cell survival by preventing the induction of apoptosis. Based on these observations, we propose that mammalian cells have a DNA replication-licensing checkpoint response to DNA damage induced during mitosis. 相似文献
170.
It is generally accepted that the basal ganglia play an important role in interval timing that requires the measurement of temporal durations. By contrast, it remains controversial whether the basal ganglia play an essential role in temporal order judgment (TOJ) of successive stimuli, a behavior that does not necessarily require the measurement of durations in time. To address this issue, we compared the effects of idiopathic Parkinson’s disease (PD) on the TOJ of two successive taps delivered to each hand, with the arms uncrossed in one condition and crossed in another. In addition to age-matched elderly participants without PD (non-PD), we examined young healthy participants so that the effect of aging could serve as a control for evaluating the effects of PD. There was no significant difference between PD and non-PD participants in any parameter of TOJ under either arm posture, although reaction time was significantly longer in PD compared with non-PD participants. By contrast, the effect of aging was apparent in both conditions. With their arms uncrossed, the temporal resolution (the interstimulus interval that yielded 84% correct responses) in elderly participants was significantly worse compared with young participants. With their arms crossed, elderly participants made more errors at longer intervals (~1 s) than young participants, although both age groups showed similar judgment reversal at moderately short intervals (~200 ms). These results indicate that the basal ganglia and dopaminergic systems do not play essential roles in tactile TOJ involving both hands and that the effect of aging on TOJ is mostly independent of the dopaminergic systems. 相似文献