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991.
Tamao Ono Yoshifumi Nakane Takahiro Wadayama Masaoki Tsudzuki Kenjiro Arisawa Shoko Ninomiya Toshihiko Suzuki Makoto Mizutani Hiroshi Kagami 《Experimental Animals》2005,54(1):7-11
The blue-breasted quail (Coturnix chinensis), the smallest species in the order Galliforms, is a candidate model animal for avian developmental engineering because it is precocious and prolific. This species requires 17 days to hatch and 8 to 9 weeks to mature to an adult body weight of about 50 g, whereas the Japanese quail (Coturnix japonica) requires 16 days to hatch and 6 to 8 weeks to mature to an adult body weight of 100 to 150 g. The early embryo is the most challenging embryonic stage in terms of culture and manipulation for avian biotechnology. We have evaluated various conditions for the culture of blue-breasted quail embryos from the blastoderm stage to hatching. A hatchability rate of 26% (10/39) is among the best of the various culture conditions examined in the present study and the embryo culture system should facilitate advances in avian biotechnology. 相似文献
992.
The Mutant Form of Acetolactate Synthase Genomic DNA from Rice is an Efficient Selectable Marker for Genetic Transformation 总被引:1,自引:0,他引:1
Keishi Osakabe Masaki Endo Kiyoshi Kawai Yaeko Nishizawa Kazuko Ono Kiyomi Abe Yuichi Ishikawa Hidemitsu Nakamura Hiroaki Ichikawa Shigeo Nishimura Tsutomu Shimizu Seiichi Toki 《Molecular breeding : new strategies in plant improvement》2005,16(4):313-320
The proper use of a marker gene in a transformation process is critical for the production of transgenic plants. However,
consumer concerns and regulatory requirements raise an objection to the presence of exogenous DNA in transgenic plants, especially
antibiotic-resistant genes and promoters derived from viruses. One approach to overcome this problem is the elimination of
marker genes from the plant genome by using several site-specific recombination systems. We propose an alternative method
to solve this problem using a marker gene exclusively derived from the host plant DNA. We cloned a genomic DNA fragment containing
regulatory and coding sequences of acetolactate synthase (ALS) gene from rice, and mutagenized the ALS gene into a herbicide-resistant
form. After transfer of this construct to the rice genome, transgenic plants were efficiently selected with a herbicide, bispyribac-sodium
salt, which inhibits the activity of wild type ALS. We also analyzed the regulatory feature of the rice ALS gene promoter
with the gusA reporter gene and revealed that GUS expression was observed constitutively in aerial parts of rice seedlings and root tips.
The marker system consisted exclusively of host plant DNA and enabled efficient selection in a monocot crop plant, rice. The
selection system can potentially be applied to generate transgenic plants of other crop species and can be expected to be
publicly acceptable. 相似文献
993.
Ohba T Watanabe H Murakami M Radovanovic M Iino K Ishida M Tosa S Ono K Ito H 《Biochemical and biophysical research communications》2008,369(2):376-381
Human coronary artery smooth muscle cell (hCASMC) proliferation is involved in the progression of coronary artery disease. Amlodipine, a widely used antihypertensive drug, exerts antiproliferative effects by increasing the expression of p21(Waf1/Cip1). Polycystic kidney disease 1 (PKD1) is also involved in cell cycle inhibition via p21(Waf1/Cip1) up-regulation. We clarified the involvement of PKD1-related signaling on hCASMCs. Cultured hCASMCs, which constitutively express PKD1, were stimulated with 5% serum. Amlodipine increased p21(Waf1/Cip1) expression in a dose- and time-dependent manner, resulting in reduced hCASMC proliferation. The inhibitory effect of amlodipine was mimicked by overexpression of PKD1 and was reversed by a dominant-negative version of PKD1 (R4227X). Immunoblot analysis showed that phosphorylated JAK2 was increased by amlodipine treatment or PKD1 overexpression. A luciferase assay revealed that the overexpression of PKD1 induced STAT1 enhancer activity. These data suggest that PKD1 contributes to the antiproliferative effect of amlodipine on hCASMCs via JAK/STAT signaling and p21(Waf1/Cip1) up-regulation. 相似文献
994.
Bone morphogenetic proteins (BMPs) are morphogens with long-range signaling activities. BMP-7 is secreted as a stable complex consisting of a growth factor noncovalently associated with two propeptides. In other transforming growth factor-β-like growth factor complexes, the prodomain (pd) confers latency to the complex. However, we detected no difference in signaling capabilities between the growth factor and the BMP-7 complex in multiple in vitro bioactivity assays. Biochemical and biophysical methods elucidated the interaction between the BMP-7 complex and the extracellular domains of its type I and type II receptors. Results showed that type II receptors, such as BMP receptor II, activin receptor IIA, and activin receptor IIB, competed with the pd for binding to the growth factor and displaced the pd from the complex. In contrast, type I receptors interacted with the complex without displacing the pd. These studies suggest a new model for growth factor activation in which proteases or other extracellular molecules are not required and provide a molecular mechanism consistent with a role for BMP receptors in the establishment of early morphogen gradients. 相似文献
995.
Watari K Nakao S Fotovati A Basaki Y Hosoi F Bereczky B Higuchi R Miyamoto T Kuwano M Ono M 《Biochemical and biophysical research communications》2008,377(3):826-831
The close association of inflammation, angiogenesis and cancer progression is now highlighted, and in this study we especially focused on a close association of inflammation and lymphangiogenesis. We found that proinflammatory cytokine, interleukin-1β (IL-1β), could induce lymphangiogenesis in mouse cornea through enhanced production of potent lymphangiogenic factors, VEGF-A, VEGF-C and VEGF-D. IL-1β-induced lymphangiogenesis, but not angiogenesis, was inhibited by administration of a selective anti-VEGF receptor-3 (VEGFR-3) neutralizing antibody. And in mouse cornea we observed recruitment of monocyte/macrophages and neutrophils by IL-1β implanted cornea. Depletion of macrophages by a bisphosphonate encapsulated in liposomes inhibited this IL-1β-induced lymphangiogenesis and also up-regulation of VEGF-A, VEGF-C, and VEGF-D. Furthermore, IL-1β-induced lymphangiogenesis and angiogenesis were suppressed by NF-κB inhibition with marked suppression of VEGF-A, VEGF-C, and VEGF-D expression. 相似文献
996.
Sudo E Itouga M Yoshida-Hatanaka K Ono Y Sakakibara H 《Journal of experimental botany》2008,59(12):3465-3474
Gene expression in response to Cu stress in rice leaves was quantified using DNA microarray (Agilent 22K Rice Oligo Microarray) and real-time PCR technology. Rice plants were grown in hydroponic solutions containing 0.3 (control), 10, 45, or 130 microM of CuCl(2), and Cu accumulation and photosynthesis inhibition were observed in leaves within 1 d of the start of treatment. Microarray analysis flagged 305 Cu-responsive genes, and their expression profile showed that a large proportion of general and defence stress response genes are up-regulated under excess Cu conditions, whereas photosynthesis and transport-related genes are down-regulated. The Cu sensitivity of each Cu-responsive gene was estimated by the median effective concentration value (EC50) and the range of fold-changes (F) under the highest (130 microM) Cu conditions (|log(2)F|(130)). Our results indicate that defence-related genes involved in phytoalexin and lignin biosynthesis were the most sensitive to Cu, and that plant management of abiotic and pathogen stresses has overlapping components, possibly including signal transduction. 相似文献
997.
Koppang EO Bjerkås I Haugarvoll E Chan EK Szabo NJ Ono N Akikusa B Jirillo E Poppe TT Sveier H Tørud B Satoh M 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(7):4807-4814
Over half of the salmon consumed globally are farm-raised. The introduction of oil-adjuvanted vaccines into salmon aquaculture made large-scale production feasible by preventing infections. The vaccines that are given i.p. contain oil adjuvant such as mineral oil. However, in rodents, a single i.p. injection of adjuvant hydrocarbon oil induces lupus-like systemic autoimmune syndrome, characterized by autoantibodies, immune complex glomerulonephritis, and arthritis. In the present study, whether the farmed salmon that received oil-adjuvanted vaccine have autoimmune syndrome similar to adjuvant oil-injected rodents was examined. Sera and tissues were collected from vaccinated or unvaccinated Atlantic salmon (experimental, seven farms) and wild salmon. Autoantibodies (immunofluorescence, ELISA, and immunoprecipitation) and IgM levels (ELISA) in sera were measured. Kidneys and livers were examined for pathology. Autoantibodies were common in vaccinated fish vs unvaccinated controls and they reacted with salmon cells/Ags in addition to their reactivity with mammalian Ags. Diffuse nuclear/cytoplasmic staining was common in immunofluorescence but some had more specific patterns. Serum total IgM levels were also increased in vaccinated fish; however, the fold increase of autoantibodies was much more than that of total IgM. Sera from vaccinated fish immunoprecipitated ferritin and approximately 50% also reacted with other unique proteins. Thrombosis and granulomatous inflammation in liver, and immune-complex glomerulonephritis were common in vaccinated fish. Autoimmunity similar to the mouse model of adjuvant oil-induced lupus is common in vaccinated farmed Atlantic salmon. This may have a significant impact on production loss, disease of previously unknown etiology, and future strategies of vaccines and salmon farming. 相似文献
998.
Sengle G Charbonneau NL Ono RN Sasaki T Alvarez J Keene DR Bächinger HP Sakai LY 《The Journal of biological chemistry》2008,283(20):13874-13888
Both latent transforming growth factor-beta (TGF-beta)-binding proteins fibrillins are components of microfibril networks, and both interact with members of the TGF-beta family of growth factors. Interactions between latent TGF-beta-binding protein-1 and TGF-beta and between fibrillin-1 and bone morphogenetic protein-7 (BMP-7) are mediated by the prodomain of growth factor complexes. To extend this information, investigations were performed to test whether stable complexes are formed by additional selected TGF-beta family members. Using velocity sedimentation in sucrose gradients as an assay, complex formation was demonstrated for BMP-7 and growth and differentiation factor-8 (GDF-8), which are known to exist in prodomain/growth factor complexes. Comparison of these results with complex formation by BMP-2, BMP-4 (full-length and shortened propeptides), BMP-10, and GDF-5 allowed us to conclude that all, except for BMP-2 and the short BMP-4 propeptides, formed complexes with their growth factors. Using surface plasmon resonance, binding affinities between fibrillin and all propeptides were determined. Binding studies revealed that the N-terminal end of fibrillin-1 serves as a universal high affinity docking site for the propeptides of BMP-2, -4, -7, and -10 and GDF-5, but not GDF-8, and located the BMP/GDF binding site within the N-terminal domain in fibrillin-1. Rotary shadowing electron microscopy of molecules of BMP-7 complex bound to fibrillin-1 confirmed these findings and also showed that prodomain binding targets the growth factor to fibrillin. Immunolocalization of BMP-4 demonstrated fibrillar staining limited to certain tissues, indicating tissue-specific targeting of BMP-4. These data implicate the fibrillin microfibril network in the extracellular control of BMP signaling and demonstrate differences in how prodomains target their growth factors to the extracellular space. 相似文献
999.
The gelsolin family of proteins is a major class of actin regulatory proteins that sever, cap, and nucleate actin filaments in a calcium-dependent manner and are involved in various cellular processes. Typically, gelsolin-related proteins have three or six repeats of gelsolin-like (G) domain, and each domain plays a distinct role in severing, capping, and nucleation. The Caenorhabditis elegans gelsolin-like protein-1 (gsnl-1) gene encodes an unconventional gelsolin-related protein with four G domains. Sequence alignment suggests that GSNL-1 lacks two G domains that are equivalent to fourth and fifth G domains of gelsolin. In vitro, GSNL-1 severed actin filaments and capped the barbed end in a calcium-dependent manner. However, unlike gelsolin, GSNL-1 remained bound to the side of F-actin with a submicromolar affinity and did not nucleate actin polymerization, although it bound to G-actin with high affinity. These results indicate that GSNL-1 is a novel member of the gelsolin family of actin regulatory proteins and provide new insight into functional diversity and evolution of gelsolin-related proteins. 相似文献
1000.
Hayashi C Ono Y Doi N Kitamura F Tagami M Mineki R Arai T Taguchi H Yanagida M Hirner S Labeit D Labeit S Sorimachi H 《The Journal of biological chemistry》2008,283(21):14801-14814
p94/calpain 3 is a skeletal muscle-specific Ca(2+)-regulated cysteine protease (calpain), and genetic loss of p94 protease activity causes muscular dystrophy (calpainopathy). In addition, a small in-frame deletion in the N2A region of connectin/titin that impairs p94-connectin interaction causes a severe muscular dystrophy (mdm) in mice. Since p94 via its interaction with the N2A and M-line regions of connectin becomes part of the connectin filament system that serves as a molecular scaffold for the myofibril, it has been proposed that structural and functional integrity of the p94-connectin complex is essential for health and maintenance of myocytes. In this study, we have surveyed the interactions made by p94 and connectin N2A inside COS7 cells. This revealed that p94 binds to connectin at multiple sites, including newly identified loci in the N2A and PEVK regions of connectin. Functionally, p94-N2A interactions suppress p94 autolysis and protected connectin from proteolysis. The connectin N2A region also contains a binding site for the muscle ankyrin repeat proteins (MARPs), a protein family involved in the cellular stress responses. MARP2/Ankrd2 competed with p94 for binding to connectin and was also proteolyzed by p94. Intriguingly, a connectin N2A fragment with the mdm deletion possessed enhanced resistance to proteases, including p94, and its interaction with MARPs was weakened. Our data support a model in which MARP2-p94 signaling converges within the N2A connectin segment and the mdm deletion disrupts their coordination. These results also implicate the dynamic nature of connectin molecule as a regulatory scaffold of p94 functions. 相似文献