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71.
We investigated the genetic structure of populations of the brackish-water crab Deiratonotus cristatus (de Man, 1895) (family Camptandriidae) on the Japanese coast, together with morphological and the ecological variations. Genetic characteristics of the local populations based on mitochondrial DNA COI sequence data have revealed genetic differentiation between many populations, with the haplotype networks forming three geographical clades: a clade occurring on the Pacific coast, one occurring predominantly in northern Hokkaido, Kyushu and the Seto Inland Sea, and a third occurring in the Ryukyu Islands. Male pleopod morphology, carapace length relative to carapace width, and carapace width of adult crabs varied inconsistently among the geographic groups corresponding to the three clades. Life history traits were similar throughout, although differences in the breeding season were apparent between populations on the Pacific coast, and in the Seto Inland Sea and the Ryukyu Islands. 相似文献
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Isamu Tsuji Shuji Sato Kentaro Otake Takahiro Watanabe Hiroko Kamada Tomofumi Kurokawa 《MABS-AUSTIN》2012,4(6):732-739
Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a member of the epidermal growth factor family. The accumulated evidence on the tumor-progressing roles of HB-EGF has suggested that HB-EGF-targeted cancer therapy is expected to be promising. However, the generation of neutralizing anti-HB-EGF monoclonal antibodies (mAbs) has proved difficult. To overcome this difficulty, we performed a hybridoma approach using mice from different genetic backgrounds, as well as different types of HB-EGF immunogens. To increase the number of hybridoma clones to screen, we used an electrofusion system to generate hybridomas and a fluorometric microvolume assay technology to screen anti-HB-EGF mAbs. We succeeded in obtaining neutralizing anti-HB-EGF mAbs, primarily from BALB/c and CD1 mice, and these were classified into 7 epitope bins based on their competitive binding to the soluble form of HB-EGF (sHB-EGF). The mAbs showed several epitope bin-dependent characteristics, including neutralizing and binding activity to human sHB-EGF, cross-reactivity to mouse/rat sHB-EGF and binding activity to the precursor form of HB-EGF. The neutralizing activity was also validated in colony formation assays. Interestingly, we found that the populations of mAb bins and the production rates of the neutralizing mAbs were strikingly different by mouse strain and by immunogen type. We succeeded in generating a variety of neutralizing anti-HB-EGF mAbs, including potent sHB-EGF neutralizers that may have potential as therapeutic agents for treating HB-EGF-dependent cancers. Our results also suggest that immunization approaches using different mouse strains and immunogen types affect the biological activity of individual neutralizing antibodies. 相似文献
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Motoshi Nagao Kenneth Campbell Kevin Burns Chia-Yi Kuan Andreas Trumpp Masato Nakafuku 《The Journal of cell biology》2008,183(7):1243-1257
The modes of proliferation and differentiation of neural stem cells (NSCs) are coordinately controlled during development, but the underlying mechanisms remain largely unknown. In this study, we show that the protooncoprotein Myc and the tumor suppressor p19ARF regulate both NSC self-renewal and their neuronal and glial fate in a developmental stage–dependent manner. Early-stage NSCs have low p19ARF expression and retain a high self-renewal and neurogenic capacity, whereas late-stage NSCs with higher p19ARF expression possess a lower self-renewal capacity and predominantly generate glia. Overexpression of Myc or inactivation of p19ARF reverts the properties of late-stage NSCs to those of early-stage cells. Conversely, inactivation of Myc or forced p19ARF expression attenuates self-renewal and induces precocious gliogenesis through modulation of the responsiveness to gliogenic signals. These actions of p19ARF in NSCs are mainly mediated by p53. We propose that opposing actions of Myc and the p19ARF–p53 pathway have important functions in coordinated developmental control of self-renewal and cell fate choices in NSCs. 相似文献
76.
Sugimori M Nagao M Parras CM Nakatani H Lebel M Guillemot F Nakafuku M 《Development (Cambridge, England)》2008,135(7):1271-1281
77.
Hiroki Inoue Tomoko Kudo Hiroshi Kamada Makoto Kimura Isamu Yamaguchi Hiroshi Hamamoto 《Plant Physiology and Biochemistry》2005,43(12):1089-1094
At concentrations greater than 0.1 mM, CuSO(4) provoked a rapid and sustained increase in the cytosolic free Ca(2+) concentration ([Ca(2+)](cyt)), in tobacco suspension culture cells expressing apoaequorin, a Ca(2+)-sensitive photoprotein. The increase was suppressed by treatment with LaCl(3), indicating that the increase is due to an influx of Ca(2+) from the apoplast through plasma membrane Ca(2+) channels. Although stimulation of H(2)O(2) production upon the CuSO(4) treatment (0.1 mM) was observed, treatment with catalase did not inhibit the increase in [Ca(2+)](cyt), and treatment with H(2)O(2) dose-dependently suppressed or delayed the increase. These results suggested that active oxygen species generated through copper-mediated reactions, or copper-mediated oxidative damages to plasma membrane, are not responsible for the increase. Treatment with sulfhydryl reagents, which alkylate or oxidize thiol groups, or acidification of the culture medium suppressed the increase in [Ca(2+)](cyt). These results demonstrated that copper causes an influx of Ca(2+) through plasma membrane Ca(2+) channels, and that plasma membrane thiol groups play an important role in activating the Ca(2+) channels. 相似文献
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Poly-N-acetyllactosamines were prepared from Ehrlich carcinoma cells cultured in the presence of [14C]galactose. Methylation analysis indicated that 31% of the galactose was in the non-reducing end. Of it, 77% was cleaved by alpha-galactosidase, and 56% was released as a disaccharide by endo-beta-galactosidase C. Methylation analysis confirmed that the released disaccharide was mostly Gal alpha 1----3Gal. Therefore, Gal alpha 1----3Gal structure, not Gal alpha 1----3(Gal alpha 1----6)Gal structure, was the major alpha-galactosyl structure in the poly-N-acetyllactosamines synthesized. Furthermore, alpha-galactosidase digestion did not change the content of disubstituted galactosyl residues. Thus, Gal alpha 1----3(Gal alpha 1----6)Gal structure, which was suggested to be the sole non-reducing terminal structure of poly-N-acetyllactosamines of Ehrlich carcinoma cells, was not detected in significant amounts under the present experimental conditions. 相似文献