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101.
Expression and purification of recombinant swine interleukin-4 总被引:4,自引:0,他引:4
Nuntaprasert A Mori Y Fujita K Yoneda M Miura R Tsukiyama-Kohara K Kai C 《Comparative immunology, microbiology and infectious diseases》2005,28(1):17-35
The swine interleukin-4 (SwIL-4) cDNA was cloned by RT-PCR. It was expressed using an expression vector pQE30 in E. coli, a baculovirus AcNPV vector pVL1392 in insect cells, and a pCAGGS vector in mammalian cells. The rSwIL-4 proteins expressed from bacteria and insect cells were purified using a chelating affinity column and a mAb-coupled immunoaffinity column. The amount of the products and their bioactivities were compared. All recombinant cytokines were efficiently reacted with the specific antibodies and the molecular weight of rSwIL-4 was approximately 16 kDa in E. coli, 15 and 18 kDa in insect cells, and 15 and 20 kDa in mammalian cells. Variations of molecular weight observed in insect and mammalian cells were probably due to different modification ways of glycosylation. All these recombinant proteins retained their antigenicity and were biologically active in inducing human TF-1 cell proliferation in vitro. The simple purification method will make it possible to evaluate the in vitro and in vivo effects of IL-4 in pigs. 相似文献
102.
Nakanishi M Kuwamura M Yamate J Fujita D Sasai H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(9):939-941
A 6-year-old female ferret had a firm mass 2 cm in diameter in the pyloric region of the stomach. Histopathologically, the mass was composed of neoplastic proliferation of well-differentiated epithelial cells, showing tubular or glandular growth patterns. Osseous metaplastic foci were often found in the tumor. Tumor cells showed a positive reaction for immunohistochemistry against bone morphogenetic protein-6, an osteogenic factor. A diagnosis of gastric adenocarcinoma with ossification was made. 相似文献
103.
104.
Rensing SA Lang D Zimmer AD Terry A Salamov A Shapiro H Nishiyama T Perroud PF Lindquist EA Kamisugi Y Tanahashi T Sakakibara K Fujita T Oishi K Shin-I T Kuroki Y Toyoda A Suzuki Y Hashimoto S Yamaguchi K Sugano S Kohara Y Fujiyama A Anterola A Aoki S Ashton N Barbazuk WB Barker E Bennetzen JL Blankenship R Cho SH Dutcher SK Estelle M Fawcett JA Gundlach H Hanada K Heyl A Hicks KA Hughes J Lohr M Mayer K Melkozernov A Murata T Nelson DR Pils B Prigge M Reiss B Renner T Rombauts S Rushton PJ 《Science (New York, N.Y.)》2008,319(5859):64-69
We report the draft genome sequence of the model moss Physcomitrella patens and compare its features with those of flowering plants, from which it is separated by more than 400 million years, and unicellular aquatic algae. This comparison reveals genomic changes concomitant with the evolutionary movement to land, including a general increase in gene family complexity; loss of genes associated with aquatic environments (e.g., flagellar arms); acquisition of genes for tolerating terrestrial stresses (e.g., variation in temperature and water availability); and the development of the auxin and abscisic acid signaling pathways for coordinating multicellular growth and dehydration response. The Physcomitrella genome provides a resource for phylogenetic inferences about gene function and for experimental analysis of plant processes through this plant's unique facility for reverse genetics. 相似文献
105.
Sato M Ishikawa T Ujihara N Yoshida S Fujita M Mochizuki M Asada A 《Science (New York, N.Y.)》2011,332(6036):1395
The moment magnitude (M(w)) = 9.0 2011 Tohoku-Oki mega-thrust earthquake occurred off the coast of northeastern Japan. Combining Global Positioning System (GPS) and acoustic data, we detected very large sea-floor movements associated with this event directly above the focal region. An area with more than 20 meters of horizontal displacement, that is, four times larger than those detected on land, stretches several tens of kilometers long along the trench; the largest amount reaches about 24 meters toward east-southeast just above the hypocenter. Furthermore, nearly 3 meters of vertical uplift occurred, contrary to observed terrestrial subsidence. 相似文献
106.
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
107.
Oscillatory expression of the bHLH factor Hes1 regulated by a negative feedback loop 总被引:1,自引:0,他引:1
Hirata H Yoshiura S Ohtsuka T Bessho Y Harada T Yoshikawa K Kageyama R 《Science (New York, N.Y.)》2002,298(5594):840-843
108.
Expression and function of the segmentation gene fushi tarazu during Drosophila neurogenesis 总被引:33,自引:0,他引:33
Segmentation genes control cell identities during early pattern formation in Drosophila. One of these genes, fushi tarazu (ftz), is now shown also to control cell fate during neurogenesis. Early in development, ftz is expressed in a striped pattern at the blastoderm stage. Later, it is transiently expressed in a specific subset of neuronal precursor cells, neurons (such as aCC, pCC, RP1, and RP2), and glia in the developing central nervous system (CNS). The function of ftz in the CNS was determined by creating ftz mutant embryos that express ftz in the blastoderm stripes but not in the CNS. In the absence of ftz CNS expression, some neurons appear normal (for example, the aCC, pCC, and RP1), whereas the RP2 neuron extends its growth cone along an abnormal pathway, mimicking its sibling (RP1), suggesting a transformation in neuronal identity. 相似文献
109.
Imtiaj Hasan Shigeki Sugawara Yuki Fujii Yasuhiro Koide Daiki Terada Naoya Iimura Toshiyuki Fujiwara Keisuke G. Takahashi Nobuhiko Kojima Sultana Rajia Sarkar M. A. Kawsar Robert A. Kanaly Hideho Uchiyama Masahiro Hosono Yukiko Ogawa Hideaki Fujita Jiharu Hamako Taei Matsui Yasuhiro Ozeki 《Marine drugs》2015,13(12):7377-7389
MytiLec; a novel lectin isolated from the Mediterranean mussel (Mytilus galloprovincialis); shows strong binding affinity to globotriose (Gb3: Galα1-4Galβ1-4Glc). MytiLec revealed β-trefoil folding as also found in the ricin B-subunit type (R-type) lectin family, although the amino acid sequences were quite different. Classification of R-type lectin family members therefore needs to be based on conformation as well as on primary structure. MytiLec specifically killed Burkitt''s lymphoma Ramos cells, which express Gb3. Fluorescein-labeling assay revealed that MytiLec was incorporated inside the cells. MytiLec treatment of Ramos cells resulted in activation of both classical MAPK/ extracellular signal-regulated kinase and extracellular signal-regulated kinase (MEK-ERK) and stress-activated (p38 kinase and JNK) Mitogen-activated protein kinases (MAPK) pathways. In the cells, MytiLec treatment triggered expression of tumor necrosis factor (TNF)-α (a ligand of death receptor-dependent apoptosis) and activation of mitochondria-controlling caspase-9 (initiator caspase) and caspase-3 (activator caspase). Experiments using the specific MEK inhibitor U0126 showed that MytiLec-induced phosphorylation of the MEK-ERK pathway up-regulated expression of the cyclin-dependent kinase inhibitor p21, leading to cell cycle arrest and TNF-α production. Activation of caspase-3 by MytiLec appeared to be regulated by multiple different pathways. Our findings, taken together, indicate that the novel R-type lectin MytiLec initiates programmed cell death of Burkitt’s lymphoma cells through multiple pathways (MAPK cascade, death receptor signaling; caspase activation) based on interaction of the lectin with Gb3-containing glycosphingolipid-enriched microdomains on the cell surface. 相似文献
110.
ABSTRACT A selectable marker gene conferring resistance to bialaphos (BI) was introduced into rice blast isolate Y90-71BI and another conferring resistance to blasticidin S (BS) into isolate 3514-R-2BS of Magnaporthe oryzae to demonstrate exchange of DNA. Colonies obtained from co-cultures of these two isolates were resistant to both BI and BS and had both resistance genes as shown by Southern blot analysis of their genomic DNA. Conidia from these BI-BS-resistant isolates had only one nucleus per cell after staining with 4',6-diamidino-2-phenylindole (DAPI). Using flow cytometry, however, these BI-BS-resistant isolates were found to be haploid. Segregation of BI-BS-resistant isolates for pathogenicity (avirulence to virulence) on rice line K59-1 was consistent with a 1:1 ratio, as was segregation for mating type. These BI-BS-resistant isolates were thus apparently derived from parasexual exchange of DNA and the segregation of pathogenicity and of mating type of the parasexual recombinants might correspond to that of the progeny of the offspring of the sexual cross. 相似文献