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21.
We investigated clonal traits in the dioecious herb Rumex acetosella to characterize sexual dimorphism in clonal forms and to correlate below-ground clonal patterns and above-ground ramet distributions.
We recorded creeping root length, branching patterns, ramet and clump (caespitose ramets from the same position on the root)
sprouting patterns, and biomass allocations in three females and males. We also estimated the patch size of flowering ramets
within a quadrat. No sexual dimorphism was detected in the frequencies of branches and flowering ramets per root length. Male
plants allocated proportionally more biomass to below-ground organs. Total root length did not differ between the sexes. Females
sprouted more clumps with fewer flowering ramets per root length than males, which sprouted fewer clumps with more flowering
ramets, which meant that clump sprouting patterns were phalanx-like in females and guerrilla-like in males. Flowering ramets
were aggregately distributed in both females and males and patch sizes were similar between sexes, indicating that the spreader
propagations were not found in the guerrilla-like males. We assumed that sexual dimorphism occurred in response to physiological
integration for higher reproductive effort in females. 相似文献
22.
JSAP1, a Novel Jun N-Terminal Protein Kinase (JNK)-Binding Protein That Functions as a Scaffold Factor in the JNK Signaling Pathway 下载免费PDF全文
Michihiko Ito Katsuji Yoshioka Mizuho Akechi Shinya Yamashita Nobuhiko Takamatsu Kenji Sugiyama Masahiko Hibi Yusaku Nakabeppu Tadayoshi Shiba Ken-Ichi Yamamoto 《Molecular and cellular biology》1999,19(11):7539-7548
The major components of the mitogen-activated protein kinase (MAPK) cascades are MAPK, MAPK kinase (MAPKK), and MAPKK kinase (MAPKKK). Recent rapid progress in identifying members of MAPK cascades suggests that a number of such signaling pathways exist in cells. To date, however, how the specificity and efficiency of the MAPK cascades is maintained is poorly understood. Here, we have identified a novel mouse protein, termed Jun N-terminal protein kinase (JNK)/stress-activated protein kinase-associated protein 1 (JSAP1), by a yeast two-hybrid screen, using JNK3 MAPK as the bait. Of the mammalian MAPKs tested (JNK1, JNK2, JNK3, ERK2, and p38alpha), JSAP1 preferentially coprecipitated with the JNKs in cotransfected COS-7 cells. JNK3 showed a higher binding affinity for JSAP1, compared with JNK1 and JNK2. In similar cotransfection studies, JSAP1 also interacted with SEK1 MAPKK and MEKK1 MAPKKK, which are involved in the JNK cascades. The regions of JSAP1 that bound JNK, SEK1, and MEKK1 were distinct from one another. JNK and MEKK1 also bound JSAP1 in vitro, suggesting that these interactions are direct. In contrast, only the activated form of SEK1 associated with JSAP1 in cotransfected COS-7 cells. The unstimulated SEK1 bound to MEKK1; thus, SEK1 might indirectly associate with JSAP1 through MEKK1. Although JSAP1 coprecipitated with MEK1 MAPKK and Raf-1 MAPKKK, and not MKK6 or MKK7 MAPKK, in cotransfected COS-7 cells, MEK1 and Raf-1 do not interfere with the binding of SEK1 and MEKK1 to JSAP1, respectively. Overexpression of full-length JSAP1 in COS-7 cells led to a considerable enhancement of JNK3 activation, and modest enhancement of JNK1 and JNK2 activation, by the MEKK1-SEK1 pathway. Deletion of the JNK- or MEKK1-binding regions resulted in a significant reduction in the enhancement of the JNK3 activation in COS-7 cells. These results suggest that JSAP1 functions as a scaffold protein in the JNK3 cascade. We also discuss a scaffolding role for JSAP1 in the JNK1 and JNK2 cascades. 相似文献
23.
Katsuji Haneda Takefumi Oishi Hiroshi Kimura Toshiyuki Inazu 《Bioorganic & medicinal chemistry》2018,26(8):2092-2098
A microbioreactor immobilized with a synthase-type mutant enzyme, Endo-M-N175Q (glycosynthase) of endo-β-N-acetylglucosaminidase derived from Mucor hiemalis (Endo-M), was constructed and used for glycoconjugate synthesis. The transglycosylation was performed with a reaction mixture containing an oxazoline derivative of sialo complex-type glycoside (SG), which was prepared from a sialo complex-type glycopeptide SGP derived from hen egg yolk, as a glycosyl donor and N-Fmoc-N-acetylglucosaminyl-l-asparagine [Fmoc-Asn(GlcNAc)-OH] as an acceptor. The reaction mixture was injected into a glycosynthase microbioreactor at a constant flow rate. Highly efficient and nearly stoichiometric transglycosylation occurred in the microbioreactor, and the transglycosylation product was eluted from the other end of the reactor. The glycosynthase microbioreactor was stable and could be used repeatedly for a long time. 相似文献
24.
Ueki Atsuko Takehara Toshiaki Ishioka Gen Kaku Nobuo Ueki Katsuji 《Applied microbiology and biotechnology》2017,101(22):8267-8277
Applied Microbiology and Biotechnology - Biological soil disinfestation (BSD) involves elimination of soil-borne plant pathogens in an environmentally friendly manner. Two anaerobic bacterial... 相似文献
25.
Toshiyuki Masuzawa Tetsuro Komikado Kazuhide Kaneda Takako Fukui Katsuji Sawaki Yasutake Yanagihara 《FEMS microbiology letters》1997,153(2):287-293
Borrelia afzelii, B. japonica, and `B. tanukii' isolated from various sources and geographical origins in Japan were characterized by restriction fragment length polymorphism (RFLP) analysis and sequencing analysis of the outer surface protein C (OspC) amplicon. B. afzelii and `B. tanukii' generated variable RFLP patterns and differences in ospC gene sequence were confirmed. In contrast, 26 isolates of B. japonica generated one OspC RFLP type, and sequence similarity between B. japonica ranged from 96.4 to 99.7%. These finding suggests that B. japonica is unique in comparison with other members of B. burgdorferi sensu lato species with respect to homogeneity of the ospC gene. 相似文献
26.
Day-night changes in production of carbohydrate and protein by natural phytoplankton population from Lake Biwa, Japan 总被引:2,自引:0,他引:2
Hama Takeo; Matsunaga Katsuji; Handa Nobuhiko; Takahashi Mikio 《Journal of plankton research》1988,10(5):941-955
The 13C and gas chromatography-mass spectrometry (13C-GC-MS)method was applied to determine the day-night changes in thecomposition of photosynthetic products of the natural phytoplanktonpopulation from Lake Biwa, Japan. Glucose is the most abundantmonosaccharide in acid-hydrolyzable carbohydrate. The contributionof glucose was high in incubatesd samples in daytime and decreasedduring the night. Other monosaccharides (rhamnose, fucose, ribose,arabinose, xylose, mannose and galactose) and amino acids tendedto be produced throughout both day- and night-time. These resultssuggested that the carbon flows from glucose, which might constitutereserve glucan, to other monosaccharides and amino acids duringnight-time. The disproportionate production of glucose (reservedglucan) during daytime was thus partly cancelled out at night. 相似文献
27.
Recently, numerous attempts have been made to understand the dynamic behavior of complex brain systems using neural network models. The fluctuations in blood-oxygen-level-dependent (BOLD) brain signals at less than 0.1 Hz have been observed by functional magnetic resonance imaging (fMRI) for subjects in a resting state. This phenomenon is referred to as a "default-mode brain network." In this study, we model the default-mode brain network by functionally connecting neural communities composed of spiking neurons in a complex network. Through computational simulations of the model, including transmission delays and complex connectivity, the network dynamics of the neural system and its behavior are discussed. The results show that the power spectrum of the modeled fluctuations in the neuron firing patterns is consistent with the default-mode brain network's BOLD signals when transmission delays, a characteristic property of the brain, have finite values in a given range. 相似文献
28.
Masahiko Sakaguchi Kazumitsu Hanai Kunimasa Ohta Masaaki Kitajima Sachiko Matsuhashi Katsuji Hori Hiromichi Morita 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,168(4):409-416
Summary Reduced glutathione evokes a feeding response, the tentacle-ball formation inHydra japonica. This response consists of at least 5 components (R1–R5). We raised 6 monoclonal antibodies (mAbs), each of which depressed a specific subset of these components, and we also examined the immunocytochemical localization of antigens with these mAbs at light microscopic level. The 2 mAbs that depressed R2 and R4 bound to the cnidocils of the desmoneme and the stenotele nematocytes; the 3 mAbs that depressed R5 bound to the apical surface adjacent to the cnidocils of the nematocytes; and the 2 mAbs that depressed R1 and R3 bound to the apical spot structures of unidentified cells in the ectoderm.Together with the specificity of the action of the mAbs on the behavioral response, the correspondence between the effects on the response and the structures visualized with these mAbs suggests that these structures include components of the receptor-effector system relevant to chemoreception. 相似文献
29.
16S Ribosomal DNA-Based Analysis of Bacterial Diversity in Purified Water Used in Pharmaceutical Manufacturing Processes by PCR and Denaturing Gradient Gel Electrophoresis 总被引:8,自引:1,他引:8 下载免费PDF全文
Mako Kawai Eiichi Matsutera Hisashi Kanda Nobuyasu Yamaguchi Katsuji Tani Masao Nasu 《Applied microbiology》2002,68(2):699-704
The bacterial community in partially purified water, which is prepared by ion exchange from tap water and is used in pharmaceutical manufacturing processes, was analyzed by denaturing gradient gel electrophoresis (DGGE). 16S ribosomal DNA fragments, including V6, -7, and -8 regions, were amplified with universal primers and analyzed by DGGE. The bacterial diversity in purified water determined by PCR-DGGE banding patterns was significantly lower than that of other aquatic environments. The bacterial populations with esterase activity sorted by flow cytometry and isolated on soybean casein digest (SCD) and R2A media were also analyzed by DGGE. The dominant bacterium in purified water possessed esterase activity but could not be detected on SCD or R2A media. DNA sequence analysis of the main bands on the DGGE gel revealed that culturable bacteria on these media were Bradyrhizobium sp., Xanthomonas sp., and Stenotrophomonas sp., while the dominant bacterium was not closely related to previously characterized bacteria. These data suggest the importance of culture-independent methods of quality control for pharmaceutical water. 相似文献
30.
Takeshi Kawahara Akira Ichikawa Yoshinori Katakura Kiichiro Teruya Takahisa Yoshida Masahiro Kikuchi Masanori Kamei Shuichi Hashizume Sanetaka Shirahata 《Cytotechnology》2001,36(1-3):171-177
Adult T cell leukemia (ATL) is a malignant disease characterized by tumorous proliferation of CD4+ T cells infected with retrovirus human T cell leukemia virus Type-I (HTLV-I) and concurs with an autoimmune disease and cancer
due to attenuated immune response. In this study, we established ATL patient derived B-cell line TM-1 producing cancer-specific
IgM antibodies, and further characterized its antigen specificity by establishing hybridomas fused with human-mouse origin
hetero-myeloma cell line RF-S1. We established three hybridoma cell lines termed 2E12, 3E9, and 3E10, which continuously secreted
human IgM antibodies. Immunohistochemical staining of formalin-fixed tissue section using antibodies secreted from these hybridomas
showed that these antibodies specifically recognized tumor sites of human colon adenocarcinomas. Antibody produced from hybridoma
3E9 bound to some of leukemic cell lines, but not to normal human PBL, which was evidenced by the flow cytometric analysis,
indicating that antibody produced from 3E9 recognizes cell surface antigen specifically expressed in the leukemic cells.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献