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41.
Mayumi Hadano Kenlo Nishida Nasahara Takeshi Motohka Hibiki Muraoka Noda Kazutaka Murakami Masahiro Hosaka 《Ecology and evolution》2013,3(6):1798-1807
Reports indicate that leaf onset (leaf flush) of deciduous trees in cool‐temperate ecosystems is occurring earlier in the spring in response to global warming. In this study, we created two types of phenology models, one driven only by warmth (spring warming [SW] model) and another driven by both warmth and winter chilling (parallel chill [PC] model), to predict such phenomena in the Japanese Islands at high spatial resolution (500 m). We calibrated these models using leaf onset dates derived from satellite data (Terra/MODIS) and in situ temperature data derived from a dense network of ground stations Automated Meteorological Data Acquisition System. We ran the model using future climate predictions created by the Japanese Meteorological Agency's MRI‐AGCM3.1S model. In comparison to the first decade of the 2000s, our results predict that the date of leaf onset in the 2030s will advance by an average of 12 days under the SW model and 7 days under the PC model throughout the study area. The date of onset in the 2090s will advance by 26 days under the SW model and by 15 days under the PC model. The greatest impact will occur on Hokkaido (the northernmost island) and in the central mountains. 相似文献
42.
Mindy I. Davis Atsuo T. Sasaki Min Shen Brooke M. Emerling Natasha Thorne Sam Michael Rajan Pragani Matthew Boxer Kazutaka Sumita Koh Takeuchi Douglas S. Auld Zhuyin Li Lewis C. Cantley Anton Simeonov 《PloS one》2013,8(1)
Phosphoinositide kinases regulate diverse cellular functions and are important targets for therapeutic development for diseases, such as diabetes and cancer. Preparation of the lipid substrate is crucial for the development of a robust and miniaturizable lipid kinase assay. Enzymatic assays for phosphoinositide kinases often use lipid substrates prepared from lyophilized lipid preparations by sonication, which result in variability in the liposome size from preparation to preparation. Herein, we report a homogeneous 1536-well luciferase-coupled bioluminescence assay for PI5P4Kα. The substrate preparation is novel and allows the rapid production of a DMSO-containing substrate solution without the need for lengthy liposome preparation protocols, thus enabling the scale-up of this traditionally difficult type of assay. The Z’-factor value was greater than 0.7 for the PI5P4Kα assay, indicating its suitability for high-throughput screening applications. Tyrphostin AG-82 had been identified as an inhibitor of PI5P4Kα by assessing the degree of phospho transfer of γ-32P-ATP to PI5P; its inhibitory activity against PI5P4Kα was confirmed in the present miniaturized assay. From a pilot screen of a library of bioactive compounds, another tyrphostin, I-OMe tyrphostin AG-538 (I-OMe-AG-538), was identified as an ATP-competitive inhibitor of PI5P4Kα with an IC50 of 1 µM, affirming the suitability of the assay for inhibitor discovery campaigns. This homogeneous assay may apply to other lipid kinases and should help in the identification of leads for this class of enzymes by enabling high-throughput screening efforts. 相似文献
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44.
Akihiro Ohyama Junko Toyomura Toshiaki Tachibana Seiji Isonishi Haruka Takahashi Hiroshi Ishikawa 《Human cell》2016,29(4):188-196
A cell line, designated NOCC, was established from the ascites of a patient with clear cell adenocarcinoma of the ovary. The cell line has been grown without interruption and continuously propagated by serial passaging (more than 76 times) over 7 years. The cells are spherical to polygonal-shaped, display neoplastic, and pleomorphic features, and grow in a jigsaw puzzle-like pattern while forming monolayers without contact inhibition. The cells proliferate rapidly, but are easily floated as a cell sheet. The population doubling time is about 29 h. The number of chromosomes ranges from 60 to 83. The modal number of chromosomes is 70–74 at the 30th passage. NOCC cells secreted 750.5 ng/ml of VEGF over 3 days of culture. Hypoxia inducible factor-1α (HIF-1α) is a primary regulator of VEGF under hypoxic conditions. NOCC cells were not sensitive to the anticancer drugs BEV, DOX, GEM, ETP, CDDP, or TXT. The graft of NOCC cells to a scid mouse displayed similar histological aspects to the original tumor. Both the NOCC cells and the graft of the NOCC cells gave a positive PAS reaction. 相似文献
45.
Yusuke Maeda Rintaro Iwata Hara Kazutaka Nishina Kie Yoshida-Tanaka Taiichi Sakamoto Takanori Yokota 《Nucleosides, nucleotides & nucleic acids》2019,38(5):338-348
Properties of cationic peptides bearing amino or guanidino groups with various side chain lengths that bind to double stranded RNAs (dsRNAs) were investigated. Peptides with shorter side chain lengths effectively bound to dsRNAs (12mers) increasing their thermal stability. NMR measurements suggested that the cationic peptide binds to the inner side of the major groove of dsRNA. These peptides also increased the thermal stability of siRNA and effectively protected from RNase A digestion. On the other hand, both peptides containing amino groups and guanidine groups did not disturb RNAi activity. 相似文献
46.
Murayama K Shirouzu M Kawasaki Y Kato-Murayama M Hanawa-Suetsugu K Sakamoto A Katsura Y Suenaga A Toyama M Terada T Taiji M Akiyama T Yokoyama S 《The Journal of biological chemistry》2007,282(7):4238-4242
The Rac-specific guanine nucleotide exchange factor (GEF) Asef is activated by binding to the tumor suppressor adenomatous polyposis coli mutant, which is found in sporadic and familial colorectal tumors. This activated Asef is involved in the migration of colorectal tumor cells. The GEFs for Rho family GTPases contain the Dbl homology (DH) domain and the pleckstrin homology (PH) domain. When Asef is in the resting state, the GEF activity of the DH-PH module is intramolecularly inhibited by an unidentified mechanism. Asef has a Src homology 3 (SH3) domain in addition to the DH-PH module. In the present study, the three-dimensional structure of Asef was solved in its autoinhibited state. The crystal structure revealed that the SH3 domain binds intramolecularly to the DH domain, thus blocking the Rac-binding site. Furthermore, the RT-loop and the C-terminal region of the SH3 domain interact with the DH domain in a manner completely different from those for the canonical binding to a polyproline-peptide motif. These results demonstrate that the blocking of the Rac-binding site by the SH3 domain is essential for Asef autoinhibition. This may be a common mechanism in other proteins that possess an SH3 domain adjacent to a DH-PH module. 相似文献
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48.
Yoko Nakagawa Naofumi Nakayama Hitoshi Goto Ikuhide Fujisawa Soda Chanthamath Kazutaka Shibatomi Seiji Iwasa 《Chirality》2019,31(1):52-61
Computational chemical analysis of Ru(II)‐Pheox–catalyzed highly enantioselective intramolecular cyclopropanation reactions was performed using density functional theory (DFT). In this study, cyclopropane ring–fused γ‐lactones, which are 5.8 kcal/mol more stable than the corresponding minor enantiomer, are obtained as the major product. The results of the calculations suggest that the enantioselectivity of the Ru(II)‐Pheox–catalyzed intramolecular cyclopropanation reaction is affected by the energy differences between the starting structures 5l and 5i . The reaction pathway was found to be a stepwise mechanism that proceeds through the formation of a metallacyclobutane intermediate. This is the first example of a computational chemical analysis of enantioselective control in an intramolecular carbene‐transfer reaction using C1‐symmetric catalysts. 相似文献
49.
50.
Hosoe T Nozawa K Kawahara N Fukushima K Nishimura K Miyaji M Kawai K 《Mycopathologia》1999,146(1):9-12
An indole derivative, schizocommunin, was isolated along with indigotin (indigo), indirubin, isatin, and tryptanthrin, from
the liquid culture medium in which a culture of Schizophyllum commune, isolated from the bronchus of a human patient with allergic bronchopulmonary mycosis, had been grown. The structure of schizocommunin
was established by spectroscopic investigation. Schizocommunin showed the strong cytotoxicity against murine lymphoma cells.
The assignments of the 1H- and 13C-NMR signals of indigotin were also listed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献