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851.
852.
ANGUSTIFOLIA (AN) is the first C-terminal binding protein (CtBP) gene from plants and controls leaf width and pattern of trichome branching in Arabidopsis thaliana (L.) Heynh. We characterized an ortholog of AN from Ipomoea nil (L.) Roth (Japanese morning glory) and designated it Ipomoea nil's AN (IAN). IAN is a single-copy gene in the genome and is expressed ubiquitously in various organs of I. nil. IAN contains not only a D2-HDH motif, which is highly conserved within the CtBP family, but also LXCXE, NLS and PEST motifs, which are specific to the AN subfamily. The expression of IAN cDNA driven by the cauliflower mosaic virus 35S promoter restored a defect in leaf expansion in the leaf width direction in the angustifolia-1 (an-1) mutant of Arabidopsis, suggesting that IAN retains a common function with AN. In contrast, the complementation by IAN of a defect in the trichome branching pattern on the leaf surface of the an-1 mutant was less effective than that observed for leaf shape. These results suggest that the mechanisms by which AN regulates leaf width and trichome branching are separable. 相似文献
853.
Nakajima Y Sasaki T Remijn GB Ueda K 《Journal of PHYSIOLOGICAL ANTHROPOLOGY and Applied Human Science》2004,23(6):345-349
Several illusory phenomena in auditory perception are accounted for by using the event construction model presented by Nakajima et al. (2000) in order to explain the gap transfer illusion. This model assumes that onsets and offsets of sounds are detected perceptually as if they were independent auditory elements. They are connected to one another according to the proximity principle to constitute auditory events. This model seems to contribute to a general cross-modal theory of perception where the idea of edge integration plays an important role. Potential directions in which we can connect the present paradigm with speech perception are indicated, and possibilities to improve artificial auditory environments are suggested. 相似文献
854.
Alizadeh BH Sugiyama T Oritani T Kuwahara S 《Bioscience, biotechnology, and biochemistry》2002,66(2):422-425
A series of N-substituted aryl and alkyl carbamates (RNHCOOR'; R: aryl, alkyl; R': aryl, alkyl) was prepared and screened for inhibitory activity toward the germination of oat seeds. The activity of each compound was compared with that of chlorpropham (isopropyl 3-chlorocarbanilate). Some of the synthetic carbamates possessing the N-(phenylthio)methyl group, PhSCH2NHCOOR', showed inhibitory activity close or comparable to that of chlorpropham. 相似文献
855.
Growth promotion and an increase in cell wall extensibility by silicon in rice and some other Poaceae seedlings 总被引:8,自引:0,他引:8
Hossain MT Mori R Soga K Wakabayashi K Kamisaka S Fujii S Yamamoto R Hoson T 《Journal of plant research》2002,115(1117):23-27
The effect of silicon on organ growth and its mechanisms of action were studied in rice ( Oryza sativa L. cv. Koshihikari), oat ( Avena sativa L. cv. Victory), and wheat ( Triticum aestivum L. cv. Daichino-Minori) seedlings grown in the dark. Applying silicon in the form of silicic acid to these seedlings via culture solution resulted in growth promotion of third (rice) or second (oat and wheat) leaves. The optimal concentration of silicon was 5-10 mM. No growth promotion was observed in early organs, such as coleoptiles or first leaves. In silicon-treated rice third leaves, the epidermal cell length increased, especially in the basal regions, without any effect on the number of cells, showing that silicon promoted cell elongation but not cell division. Silicon also increased the cell wall extensibility significantly in the basal regions of rice third leaves. These results indicate that silicon stimulates growth of rice and some other Poaceae leaves by increasing cell wall extensibility. 相似文献
856.
Hoson T 《Journal of plant research》2002,115(4):277-282
The cell coverings of plants have two important functions in plant life. Plant cell coverings are deeply involved in the regulation
of the life cycle of plants: each stage of the life cycle, such as germination, vegetative growth, reproductive growth, and
senescence, is strongly influenced by the nature of the cell coverings. Also, the apoplast, which consists of the cell coverings,
is the field where plant cells first encounter the outer environment, and so becomes the major site of plant responses to
the environment. In the regulation of each stage of the life cycle and the response to each environmental signal, some specific
constituents of the cell coverings, such as xyloglucans in dicotyledons and 1,3,1,4-β-glucans in Gramineae, act as the key
component. The physiological functions of plant cell coverings are sustained by the metabolic turnover of these components.
The components of the cell coverings are supplied from the symplast, but then they are modified or degraded in the apoplast.
Thus, the metabolism of the cell coverings is regulated through the cross-talk between the symplast and the apoplast. The
understanding of physiological functions of plant cell coverings will be greatly advanced by the use of genomic approaches.
At the same time, we need to introduce nanobiological techniques for clarifying the minute changes in the cell coverings that
occur in a small part within each cell.
Electronic Publication 相似文献
857.
858.
Shin-ichi Yamada Toshio Ono Akio Mizuno Takayuki K Nemoto 《European journal of biochemistry》2003,270(1):146-154
The alpha isoform of human 90-kDa heat shock protein (HSP90alpha) is composed of three domains: the N-terminal (residues 1-400); middle (residues 401-615) and C-terminal (residues 621-732). The middle domain is simultaneously associated with the N- and C-terminal domains, and the interaction with the latter mediates the dimeric configuration of HSP90. Besides one in the N-terminal domain, an additional client-binding site exists in the C-terminal domain of HSP90. The aim of the present study is to elucidate the regions within the C-terminal domain responsible for the bindings to the middle domain and to a client protein, and to define the relationship between the two functions. A bacterial two-hybrid system revealed that residues 650-697 of HSP90alpha were essential for the binding to the middle domain. An almost identical region (residues 657-720) was required for the suppression of heat-induced aggregation of citrate synthase, a model client protein. Replacement of either Leu665-Leu666 or Leu671-Leu672 to Ser-Ser within the hydrophobic segment (residues 662-678) of the C-terminal domain caused the loss of bindings to both the middle domain and the client protein. The interaction between the middle and C-terminal domains was also found in human 94-kDa glucose-regulated protein. Moreover, Escherichia coli HtpG, a bacterial HSP90 homologue, formed heterodimeric complexes with HSP90alpha and the 94-kDa glucose-regulated protein through their middle-C-terminal domains. Taken together, it is concluded that the identical region including the hydrophobic segment of the C-terminal domain is essential for both the client binding and dimer formation of the HSP90-family molecular chaperone and that the dimeric configuration appears to be similar in the HSP90-family proteins. 相似文献
859.
860.
Expression of gastric gland mucous cell-type mucin in normal and neoplastic human tissues. 总被引:5,自引:0,他引:5
Kosei Nakajima Hiroyoshi Ota Mu Xia Zhang Kenji Sano Takayuki Honda Keiko Ishii Jun Nakayama 《The journal of histochemistry and cytochemistry》2003,51(12):1689-1698
Gastric gland mucous cells produce class III mucin, which is also found in Brunner's glands and mucous glands along the pancreaticobiliary tract, and in metaplasia and adenocarcinomas differentiating towards gastric mucosa. Recently, we showed that class III mucin possesses GlcNAcalpha1-->4Galbeta-->R, formed by alpha1,4-N-acetylglucosaminyltransferase (alpha4GnT). Examining the tissue-specific expression of mucin epitopes is useful to clarify cell-lineage differentiation and to identify the site of origin of metastatic carcinomas in histological specimens. Formalin-fixed, paraffin-embedded tissue sections from esophagus, stomach, colon, liver, pancreas, lung, kidney, prostate, breast, and salivary gland resected for carcinoma, as well as salivary gland adenoma, colon adenoma, and metastatic adenocarcinoma of lymph nodes from stomach, pancreas, colon, and breast, were immunostained for MUC6, alpha4GnT, and GlcNAcalpha1-->4Galbeta-->R. These were all expressed in normal, metaplastic, and adenocarcinoma tissues of stomach, pancreas, and bile duct, and in pulmonary mucinous bronchioloalveolar carcinomas. Cells expressing alpha4GnT uniformly expressed GlcNAcalpha1-->4Galbeta-->R. Only MUC6 was expressed in normal salivary glands, pancreas, seminal vesicles, renal tubules, and colon adenomas, and in normal tissue and adenocarcinomas of prostate and breast. No tissues showed immunoreactivity for alpha4GnT alone. Immunohistochemistry (IHC) profiles were similar for metastatic carcinomas and primary carcinoma tissues. The IHC profiles for MUC6, alpha4GnT, and GlcNAcalpha1-->4Galbeta-->R may be diagnostically relevant. 相似文献