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21.
Koda Y Tachida H Pang H Liu Y Soejima M Ghaderi AA Takenaka O Kimura H 《Genetics》2001,158(2):747-756
The coding sequences ( approximately 1 kb) of FUT2 [ABO-Secretor type alpha(1,2)fucosyltransferase] and of FUT6 [plasma alpha(1,3)fucosyltransferase] were analyzed for allelic polymorphism by direct sequencing in five populations. The nucleotide diversities of FUT2 estimated from pairwise sequence differences were 0.0045, 0.0042, 0.0042, 0.0009, and 0.0008 in Africans, European-Africans, Iranians, Chinese, and Japanese, respectively. The nucleotide diversities of FUT6 were 0.0024, 0.0016, 0.0015, 0.0017, and 0.0020 in Africans, European-Africans, Iranians, Chinese, and Japanese, respectively. At FUT2, excesses in pairwise sequence differences compared to the number of polymorphic sites as indicated by a significantly positive Tajima's D were observed in European-Africans and in Iranians. The data do not fit expectations of the equilibrium neutral model with an infinite number of sites. On the other hand, Tajima's D's at FUT6 in each of the five populations and at FUT2 in Africans, Chinese, and Japanese were not significantly different from zero. F(ST) between the Asians and the others measured at FUT2 was higher than at FUT6. These results suggest that natural selection was responsible for the generation of the FUT2 polymorphism in European-Africans and in Iranians. 相似文献
22.
Katsumi Mizuta Chieko Abiko Yoko Aoki Tatsuya Ikeda Tsutomu Itagaki Fumio Katsushima Yuriko Katsushima Yoko Matsuzaki Masahiro Noda Hirokazu Kimura Tadayuki Ahiko 《Microbiology and immunology》2012,56(12):855-858
To clarify the epidemiology of viral acute respiratory infections (ARIs), 305 human parainfluenza virus types 1 (HPIV1), 154 HPIV2 and 574 HPIV3 strains were isolated from 16,962 nasopharyngeal swabs obtained between 2002 and 2011 at pediatric clinics in Yamagata, Japan. The total isolation frequency for HPIV1–3 was 6.1%. Unlike HPIV1 infections, HPIV3 showed clear seasonality with yearly outbreaks in the spring–summer season. HPIV2 tended to appear biannually in autumn–winter. Although no reliable techniques for the laboratory diagnosis of these infections have been established, the present results suggest that HPIV1–3 are an important causative agent of ARIs in children. 相似文献
23.
Xia Y Chackalamannil S Greenlee WJ Wang Y Hu Z Root Y Wong J Kong J Ahn HS Boykow G Hsieh Y Kurowski S Chintala M 《Bioorganic & medicinal chemistry letters》2010,20(22):6676-6679
An analog of the thrombin receptor antagonist vorapaxar (SCH 530348) with increased aqueous solubility, compound 9c (SCH 602539), was discovered through incorporation of polar substituents on the pyridine ring of the himbacine-derived lead series. This analog retained the excellent potency, pharmacokinetic and safety properties of vorapaxar while increasing the aqueous solubility by 20-fold. Also presented are in vivo evaluations of this compound in a cynomolgus monkey platelet aggregation assay and in a Folts model of thrombosis in anesthetized monkeys. 相似文献
24.
Xiaofei Wang Hongyu Wang Aodon-geril Yujing Shu Yuriko Momotani Reiko Nagata 《Animal biotechnology》2013,24(1):44-49
We investigated the gene expression of matrix metalloproteinases-9 (MMP-9) and tissue inhibitors of matrix metalloproteinases-1 (TIMP-1) in peripheral blood cells from infected cattle with Mycobacterium avium subsp. paratuberculosis (Map) in the ELISA-negative subclinical stage compared with uninfected control cattle. Significant decreased MMP-9 expression and increased TIMP-1 expression were found in peripheral blood cells from Map-infected cattle after stimulation with Map lysate and Map purified protein derivative (PPD) than in control cattle by real-time RT-PCR analysis. In contrast to the uninfected controls, the activity of MMP-9 was also decreased in peripheral blood cell culture supernatants from Map-infected cattle at 24 hr after Map lysate and MapPPD stimulation by gelatin zymography analysis. As a result, the MMP-9 may play an important role in the development of Mycobacterium avium subsp. paratuberculosis disease. 相似文献
25.
26.
Carbonic anhydrase (CA) activity was detected in homogenatesfrom Anabaena variabilis ATCC 29413, M-2 and M-3, but not inthe suspension of the intact cells. Activity was higher in cellsgrown in ordinary air (low-CO2 cells) than in those grown inair enriched with 24% CO2 (high-CO2 cells). Fractionationby centrifugation indicated that the CA from A. variabilis ATCC29413 is soluble, whereas both soluble and insoluble forms existin A. variabilis M-2 and M-3. The addition of dithiothreitoland Mg2 $ greatly decreased the CA activity of A. variabilisATCC 29413. The specific activity of the CA from A. variabilis ATCC 29413was increased ca. 200 times by purification with ammonium sulfate,DEAE-Sephadex A-50 and Sephadex G-100. Major and minor CA peaksin Sephadex G-100 chromatography showed respective molecularweights of 48,000 and 25,000. The molecular weight of the CAdetermined by polyacrylamide disc gel electrophoresis was 42,000?5,000.The activity of CA was inhibited by ethoxyzolamide (I50=2.8?10-9M), acetazolamide (I50=2.5?10-7 M) and sulfanilamide (I50=2.9?10-6M). (Received January 5, 1984; Accepted April 26, 1984) 相似文献
27.
Yuriko Osakabe Kazuya Nanto Hiroko Kitamura Shinya Kawai Yuki Kondo Tomoyuki Fujii Keiji Takabe Yoshihiro Katayama Noriyuki Morohoshi 《Planta》1996,200(1):13-19
The polypeptide encoded by the partial fragment of cDNA of phenylalanine ammonia-lyase (PAL; EC 4.3.1.5), PALcDNAl (Osakabe et al., 1995, Plant Sci. 105: 217–226), isolated from Populus kitakamiensis (P. sieboldii x P. grandidentata), was expressed in Escherichia coli cells. The polypeptide was purified and an antiserum raised against it. The antiserum recognized a protein of 77 kDa on nitrocellulose blots after sodium dodecyl sulfate-poly-acrylamide gel electrophoresis of total protein and the partially purified PAL protein from P. kitakamiensis. Moreover,the antiserum recognized a protein on the blot after non-denaturing polyacrylamide gel electrophoresis of P. kitakamiensis proteins and this protein had PAL activity. Furthermore, the antibody inhibited PAL activity of extracts from stem tissues. These results showed that the antiserum against the partial PAL peptide recognized only the PAL subunits in extracts of P. kitakamiensis. Immunolocalization studies of P. kitakamiensis tissues revealed that the PAL protein was specifically localized in the xylem and the phloem fibers and no immunogold signal was found in the epidermis, the cortex, the pith, or the cambium of either stems or leaves.Abbreviations IgG
immunoglobulin G
- IPTG
isopropylthio--d-galactoside
- PAL
phenylalanine ammonia-lyase
The authors thank Dr. Kunio Hata of Nippon Paper Industries Co., Ltd. (Japan) for supplying P. kitakamiensis. This work was supported in part by a grant-in-aid for Scientific Research from the Ministry of Education, Science and Culture of Japan (No. 07406008). 相似文献
28.
Yuriko Osakabe Naoko Arinaga Taishi Umezawa Shogo Katsura Keita Nagamachi Hidenori Tanaka Haruka Ohiraki Kohji Yamada So-Uk Seo Mitsuru Abo Etsuro Yoshimura Kazuo Shinozaki Kazuko Yamaguchi-Shinozaki 《The Plant cell》2013,25(2):609-624
Osmotic adjustment plays a fundamental role in water stress responses and growth in plants; however, the molecular mechanisms governing this process are not fully understood. Here, we demonstrated that the KUP potassium transporter family plays important roles in this process, under the control of abscisic acid (ABA) and auxin. We generated Arabidopsis thaliana multiple mutants for K+ uptake transporter 6 (KUP6), KUP8, KUP2/SHORT HYPOCOTYL3, and an ABA-responsive potassium efflux channel, guard cell outward rectifying K+ channel (GORK). The triple mutants, kup268 and kup68 gork, exhibited enhanced cell expansion, suggesting that these KUPs negatively regulate turgor-dependent growth. Potassium uptake experiments using 86radioactive rubidium ion (86Rb+) in the mutants indicated that these KUPs might be involved in potassium efflux in Arabidopsis roots. The mutants showed increased auxin responses and decreased sensitivity to an auxin inhibitor (1-N-naphthylphthalamic acid) and ABA in lateral root growth. During water deficit stress, kup68 gork impaired ABA-mediated stomatal closing, and kup268 and kup68 gork decreased survival of drought stress. The protein kinase SNF1-related protein kinases 2E (SRK2E), a key component of ABA signaling, interacted with and phosphorylated KUP6, suggesting that KUP functions are regulated directly via an ABA signaling complex. We propose that the KUP6 subfamily transporters act as key factors in osmotic adjustment by balancing potassium homeostasis in cell growth and drought stress responses. 相似文献
29.
Coordinated regulation of inductive events, both spatially and temporally, during animal development ensures that tissues
are induced at their specific positions within the embryo. The ascidian brain is induced in cells at the anterior edge of
the animal hemisphere by fibroblast growth factor (FGF) signals secreted from vegetal cells. To clarify how this process is
spatially regulated, we first identified the sources of the FGF signal by examining the expression of brain markers Hr-Otx and Hr-ETR-1 in embryos in which FGF signaling is locally inhibited by injecting individual blastomeres with morpholino oligonucleotide
against Hr-FGF9/16/20, which encodes an endogenous brain inducer. The blastomeres identified as the inducing sources are A5.1 and A5.2 at the 16-cell
stage and A6.2 and A6.4 at the 24-cell stage, which are juxtaposed with brain precursors at the anterior periphery of the
embryo at the respective stages. We also showed that all the cells of the animal hemisphere are capable of expressing Hr-Otx in response to the FGF signal. These results suggest that the position of inducers, rather than competence, plays an important
role in determining which animal cells are induced to become brain tissues during ascidian embryogenesis. This situation in
brain induction contrasts with that in mesoderm induction, where the positions at which the notochord and mesenchyme are induced
are determined mainly by intrinsic competence factors that are inherited by signal-receiving cells. 相似文献
30.
In addition to its role as a neurotransmitter, dopamine can stimulate neurite outgrowth and morphological effects upon primary neurons. To investigate the signal transduction mechanisms used by dopamine in developing striatal neurons, we focused upon the effects of activating the dopamine D1 receptor. Using the D1 receptor agonist SKF38393, we found that Trk neurotrophin receptors were activated in embryonic day 18 striatal neurons. K-252a, a Trk tyrosine kinase inhibitor, and a dopamine D1 receptor antagonist could block the effects of SKF38393. The increase in TrkB phosphorylation was not the result of increased neurotrophin production. Induction of TrkB activity by SKF38393 was accompanied by the phosphorylation of several Trk signaling proteins, including phospholipase Cgamma, Akt, and MAPK. Biotinylation experiments followed by immunostaining by phospho-TrkB-specific antibodies indicated that the mechanism involved increased TrkB surface expression by dopamine D1 receptor activation. This increase in cell surface TrkB expression was dependent upon an increase in intracellular Ca(2+). These results indicate that stimulation of dopamine D1 receptors can be coupled to the neurotrophin receptor signaling to mediate the effects of dopamine upon striatal neurons. 相似文献