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51.
Okumura S Saitoh H Ishikawa T Wasano N Yamashita S Kusumoto K Akao T Mizuki E Ohba M Inouye K 《Journal of agricultural and food chemistry》2005,53(16):6313-6318
Parasporal inclusion proteins produced by Bacillus thuringiensis strain A1470 exhibit strong cytotoxicity against human leukemic T cells when activated by protease treatment. One of the cytotoxic proteins was separated by anion exchange chromatography and gel filtration chromatography and designated Cry45Aa. Its gene was then expressed in recombinant Escherichia coli, in which the Cry45Aa precursor was accumulated in an inclusion body. It was solubilized in sodium carbonate buffer and processed with proteinase K, and cytotoxic activities of the protein against various mammalian cell lines were evaluated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide assay. The protein exhibited high cytotoxic activity against CACO-2, Sawano, MOLT-4, TCS, and HL60 cells and moderate activity against U-937 DE-4, PC12, and HepG2 cells. On the other hand, the EC50 values against Jurkat, K562, HeLa, A549, Vero, COS-7, NIH3T3, CHO, and four normal tissue cells (human primary hepatocyte cells, UtSMC, MRC-5, and normal T cells) were >2 microg/mL. 相似文献
52.
Jen JC Chan WM Bosley TM Wan J Carr JR Rüb U Shattuck D Salamon G Kudo LC Ou J Lin DD Salih MA Kansu T Al Dhalaan H Al Zayed Z MacDonald DB Stigsby B Plaitakis A Dretakis EK Gottlob I Pieh C Traboulsi EI Wang Q Wang L Andrews C Yamada K Demer JL Karim S Alger JR Geschwind DH Deller T Sicotte NL Nelson SF Baloh RW Engle EC 《Science (New York, N.Y.)》2004,304(5676):1509-1513
The mechanisms controlling axon guidance are of fundamental importance in understanding brain development. Growing corticospinal and somatosensory axons cross the midline in the medulla to reach their targets and thus form the basis of contralateral motor control and sensory input. The motor and sensory projections appeared uncrossed in patients with horizontal gaze palsy with progressive scoliosis (HGPPS). In patients affected with HGPPS, we identified mutations in the ROBO3 gene, which shares homology with roundabout genes important in axon guidance in developing Drosophila, zebrafish, and mouse. Like its murine homolog Rig1/Robo3, but unlike other Robo proteins, ROBO3 is required for hindbrain axon midline crossing. 相似文献
53.
A 49-kilodalton phosphoprotein in the Drosophila photoreceptor is an arrestin homolog 总被引:10,自引:0,他引:10
T Yamada Y Takeuchi N Komori H Kobayashi Y Sakai Y Hotta H Matsumoto 《Science (New York, N.Y.)》1990,248(4954):483-486
The gene encoding the 49-kilodalton protein that undergoes light-induced phosphorylation in the Drosophila photoreceptor has been isolated and characterized. The encoded protein has 401 amino acid residues and a molecular mass of 44,972 daltons, and it shares approximately 42 percent amino acid sequence identity with arrestin (S-antigen), which has been proposed to quench the light-induced cascade of guanosine 3',5'-monophosphate hydrolysis in vertebrate photoreceptors. Unlike the 49-kilodalton protein, however, arrestin, which appears to bind to phosphorylated rhodopsin, has not itself been reported to undergo phosphorylation. In vitro, Ca2+ was the only agent found that would stimulate the phosphorylation of the 49-kilodalton protein. The phosphorylation of this arrestin-like protein in vivo may therefore be triggered by a Ca2+ signal that is likely to be regulated by light-activated phosphoinositide-specific phospholipase C. 相似文献
54.
Rice Full-Length cDNA Consortium;National Institute of Agrobiological Sciences Rice Full-Length cDNA Project Team Kikuchi S Satoh K Nagata T Kawagashira N Doi K Kishimoto N Yazaki J Ishikawa M Yamada H Ooka H Hotta I Kojima K Namiki T Ohneda E Yahagi W Suzuki K Li CJ Ohtsuki K Shishiki T;Foundation of Advancement of International Science Genome Sequencing & Analysis Group Otomo Y Murakami K Iida Y Sugano S Fujimura T Suzuki Y Tsunoda Y Kurosaki T Kodama T Masuda H Kobayashi M Xie Q Lu M 《Science (New York, N.Y.)》2003,301(5631):376-379
55.
Hatsugai N Kuroyanagi M Yamada K Meshi T Tsuda S Kondo M Nishimura M Hara-Nishimura I 《Science (New York, N.Y.)》2004,305(5685):855-858
Programmed cell death (PCD) in animals depends on caspase protease activity. Plants also exhibit PCD, for example as a response to pathogens, although a plant caspase remains elusive. Here we show that vacuolar processing enzyme (VPE) is a protease essential for a virus-induced hypersensitive response that involves PCD. VPE deficiency prevented virus-induced hypersensitive cell death in tobacco plants. VPE is structurally unrelated to caspases, although VPE has a caspase-1 activity. Thus, plants have evolved a regulated cellular suicide strategy that, unlike PCD of animals, is mediated by VPE and the cellular vacuole. 相似文献
56.
Migrating cells extend protrusions, probing the surrounding matrix in search of permissive sites to form adhesions. We found that actin fibers polymerizing along the leading edge directed local protrusions and drove synchronous sideways movement of beta1 integrin adhesion receptors. These movements lead to the clustering and positioning of conformationally activated, but unligated, beta1 integrins along the leading edge of fibroblast lamellae and growth cone filopodia. Thus, rapid actin-based movement of primed integrins along the leading edge suggests a "sticky fingers" mechanism to probe for new adhesion sites and to direct migration. 相似文献
57.
58.
Sakurai Y Itou M Barbiellini B Mijnarends PE Markiewicz RS Kaprzyk S Gillet JM Wakimoto S Fujita M Basak S Wang YJ Al-Sawai W Lin H Bansil A Yamada K 《Science (New York, N.Y.)》2011,332(6030):698-702
The high-temperature superconducting cuprate La(2-x)Sr(x)CuO(4) (LSCO) shows several phases ranging from antiferromagnetic insulator to metal with increasing hole doping. To understand how the nature of the hole state evolves with doping, we have carried out high-resolution Compton scattering measurements at room temperature together with first-principles electronic structure computations on a series of LSCO single crystals in which the hole doping level varies from the underdoped (UD) to the overdoped (OD) regime. Holes in the UD system are found to primarily populate the O 2p(x)/p(y) orbitals. In contrast, the character of holes in the OD system is very different in that these holes mostly enter Cu d orbitals. High-resolution Compton scattering provides a bulk-sensitive method for imaging the orbital character of dopants in complex materials. 相似文献
59.
Lee KJ Sasaki M Miyauchi A Kishimoto M Shimizu J Iwasaki T Miyake Y Yamada K 《Journal of zoo and wildlife medicine》2011,42(1):128-130
This report describes the use of computed tomography (CT) in a nondomestic species. Postmortem CT was performed on a red kangaroo (Macropus rufus) and a diagnosis of oral osteomyelitis was made. CT examination revealed bony remodeling of the right mandible, an intraosseous lesion of the right temporal bone, muscle necrosis around the right mandible, and the absence of the right, first, upper molar tooth. Cardiac and intrahepatic gas and a distended intestine due to postmortem gas accumulation were also seen. All the lesions identified with CT were also identified by conventional necropsy, except the cardiac and intrahepatic gases. Virtopsy may be a useful procedure for the noninvasive identification of cause of death and as a guide for necropsy in animals. 相似文献
60.
Kazuhiko Terazawa Shigehiro Ishizuka Kenji Yamada 《Soil biology & biochemistry》2007,39(10):2689-2692
We measured methane (CH4) emissions from the stem surfaces of mature Fraxinus mandshurica var. japonica trees in a floodplain forest. Flux measurements were conducted almost monthly from May to October 2005, and positive CH4 fluxes were detected throughout the study period, including the leafless season. The mean CH4 flux was 176 and 97 μg CH4 m−2 h−1 at the lower (15 cm above the ground) and upper (70 cm above the ground) stem positions, respectively. The CH4 concentration was lower in soil gas than in ambient air to a depth of at least 40 cm. One possible source of CH4 emitted from the stems might be the dissolved CH4 in groundwater; maximum concentrations were 10,000 times higher than atmospheric CH4 concentrations. Our results suggest that CH4 transport from the submerged soil layer to the atmosphere may occur through internal air spaces in tree bodies. 相似文献