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101.
102.
Hisashi Kato-Noguchi Madoka Yamamoto Kazuya Tamura Toshiaki Teruya Kiyotake Suenaga Yoshiharu Fujii 《Plant Growth Regulation》2010,60(2):127-131
Aqueous methanol extracts of rattail fescue (Vulpia myuros) inhibited the growth of roots and shoots of cress (Lepidium sativum), lettuce (Lactuca sativa), alfalfa (Medicago sativa), timothy (Phleum pratense), Digitaria sanguinalis and Lolium multiflorum. Increasing the extract concentration increased the inhibition, suggesting that rattail fescue may have growth inhibitory
substances and possess allelopathic potential. The aqueous methanol extract of rattail fescue was purified and two main inhibitory
substances were isolated and identified by spectral data as (−)-3-hydroxy-β-ionone and (+)-3-oxo-α-ionol. Both substances
inhibited root and shoot growth of cress at concentrations greater than 0.3 μM. The concentrations required for 50% growth
inhibition on root and shoot growth of cress, lettuce, alfalfa, timothy, D. sanguinalis and L. multiflorum were 2.7–19.7 μM for (−)-3-hydroxy-β-ionone, and 2.1–34.5 μM for (+)-3-oxo-α-ionol. The concentration of (−)-3-hydroxy-β-ionone
and (+)-3-oxo-α-ionol, respectively, in rattail fescue was 7.8 and 3.7 μg g−1 fresh weight. Considering the endogenous level and the inhibitory activity, (−)-3-hydroxy-β-ionone and (+)-3-oxo-α-ionol
may work as allelopathic substances in rattail fescue through the growth inhibition of neighboring plant species. 相似文献
103.
Atsushi Ishihara Fumio Matsuda Hisashi Miyagawa Kyo Wakasa 《Metabolomics : Official journal of the Metabolomic Society》2007,3(3):319-334
Advances in molecular breeding technologies have enabled manipulation of the concentrations of specific plant components by
modifying the genes that play a key role in their production. This has provided new opportunities to enhance the nutritional
quality of major crops. However, given that metabolic pathways form a highly integrated network, any alteration in a given
biosynthetic pathway is most likely to effect secondary and unpredicted changes in the metabolite profile of other pathways.
Metabolomics technologies can contribute to the efficient detection of such unexpected effects caused by genetic modification.
This has relevance not only from the perspective of safety evaluations of newly developed crops, but to basic science focused
on uncovering hitherto unknown regulatory mechanisms associated with the biosynthesis and catabolism of primary and secondary
metabolites in plants. In this review, recent advances in plant metabolic engineering for the overproduction of tryptophan
(Trp), one of the essential amino acids, are described. In particular, the efficacy of a transgene OASA1D that encodes a mutant anthranilate synthase (AS) α subunit of rice in specifically elevating levels of Trp without marked
secondary effects on the metabolite profile of rice is demonstrated. Related topics, such as regulation of Trp biosynthesis,
possible interactions between the biosyntheses of Trp and other aromatic amino acids, and translocation of Trp in are discussed
based on findings derived from metabolomic analyses of Trp-overproducing transgenic plants. 相似文献
104.
Yuka Ogata Shinsuke Morioka Kosuke Sano Bounsong Vongvichith Hiroki Eda Hisashi Kurokura Thongkhoun Khonglaliane 《Ichthyological Research》2010,57(4):389-397
The morphological development, including the pigmentation, body proportions, fins, and survival rate for 30 days after hatching, of laboratory-reared larval and juvenile Hypsibarbus malcolmi is described. Body lengths (BL) of larvae and juveniles were 2.0 ± 0.2 (mean ± SD) mm at 1 h after hatching (day 0) and 9.2 ± 0.6 mm on day 16, reaching 12.1 ± 0.9 mm on day 30. Yolk volume decreased linearly, with the yolk being completely absorbed by day 3 in all preflexion larvae (all specimens >3.2 mm BL). Feeding was observed on day 2 in fish which had rapidly undergone complete yolk absorption following mouth and anus opening on day 1, and on day 3 in all remaining fish. Myomere numbers were 20–21 + 11–12 = 31–33, although they were not clearly visible in juveniles. Melanophores were few on the body during days 0–2, but increased with growth and covered the entire upper dorsal body surface during the juvenile stage. Body proportions tended to become constant in juveniles. Notochord flexion began in larvae >5.2 mm BL on day 8, and was completed in larvae >8.4 mm BL on day 14. Specimens with full fin ray complements were initially observed on day 22 (10.4 mm BL in juveniles). All specimens >11.5 mm BL had attained the juvenile stage. A high survival rate of 92.7% was estimated on day 30. 相似文献
105.
Hatanaka H Takada S Choi YL Fujiwara S Soda M Enomoto M Kurashina K Watanabe H Yamashita Y Sugano K Mano H 《Biochemical and biophysical research communications》2007,356(3):723-726
Colorectal cancer (CRC) is one of the leading causes of cancer death in humans. In order to identify novel cancer-promoting genes in CRC, we here constructed a retroviral cDNA expression library from a CRC cell line RKO, and used it for a focus formation assay with mouse 3T3 fibroblasts, leading to the identification of 42 independent cDNAs. One of such cDNAs turned out to encode purinergic receptor P2Y, G-protein coupled, 2 (P2RY2). The oncogenic potential of P2RY2 was confirmed in vitro with the focus formation assay as well as soft agar-growth assay, and also in vivo with a tumorigenicity assay in nude mice. While our P2RY2 cDNA encodes a protein with two amino-acid substitutions compared to the reported one, we have confirmed that the wild-type P2RY2 has a strong transforming potential as well. These results indicate an unexpected role of P2RY2 in the carcinogenesis of human cancers. 相似文献
106.
Hisashi Yagi Daisaku Ozawa Kazumasa Sakurai Toru Kawakami Hiroki Kuyama Osamu Nishimura Toshinori Shimanouchi Ryoichi Kuboi Hironobu Naiki Yuji Goto 《The Journal of biological chemistry》2010,285(25):19660-19667
The amyloid deposition of amyloid β (Aβ) peptides is a critical pathological event in Alzheimer disease (AD). Preventing the formation of amyloid deposits and removing preformed fibrils in tissues are important therapeutic strategies against AD. Previously, we reported the destruction of amyloid fibrils of β2-microglobulin K3 fragments by laser irradiation coupled with the binding of amyloid-specific thioflavin T. Here, we studied the effects of a laser beam on Aβ fibrils. As was the case for K3 fibrils, extensive irradiation destroyed the preformed Aβ fibrils. However, irradiation during spontaneous fibril formation resulted in only the partial destruction of growing fibrils and a subsequent explosive propagation of fibrils. The explosive propagation was caused by an increase in the number of active ends due to breakage. The results not only reveal a case of fragmentation-induced propagation of fibrils but also provide insights into therapeutic strategies for AD. 相似文献
107.
Junko Ito Masahiko Ito Hirohide Nambu Toru Fujikawa Kenichi Tanaka Hisashi Iwaasa Shigeru Tokita 《Cell and tissue research》2009,338(2):257-269
G-protein-coupled receptors (GPCRs) constitute the largest family of transmembrane receptors and regulate a variety of physiological
and disease processes. Although the roles of many non-odorant GPCRs have been identified in vivo, several GPCRs remain orphans
(oGPCRs). The gastrointestinal (GI) tract is the largest endocrine organ and is a promising target for drug discovery. Given
their close link to physiological function, the anatomical and histological expression profiles of benchmark GI-related GPCRs,
such as the cholecystokinin-1 receptor and GPR120, and 106 oGPCRs were investigated in the mucosal and muscle-myenteric nerve
layers in the GI tract of C57BL/6J mice by quantitative real-time polymerase chain reaction. The mRNA expression patterns
of these benchmark molecules were consistent with previous in situ hybridization and immunohistochemical studies, validating
the experimental protocols in this study. Of 96 oGPCRs with significant mRNA expression in the GI tract, several oGPCRs showed
unique expression patterns. GPR85, GPR37, GPR37L1, brain-specific angiogenesis inhibitor (BAI) 1, BAI2, BAI3, and GPRC5B mRNAs
were preferentially expressed in the muscle-myenteric nerve layer, similar to GPCRs that are expressed in both the central
and enteric nerve systems and that play multiple regulatory roles throughout the gut-brain axis. In contrast, GPR112, trace
amine-associated receptor (TAAR) 1, TAAR2, and GPRC5A mRNAs were preferentially expressed in the mucosal layer, suggesting
their potential roles in the regulation of secretion, immunity, and epithelial homeostasis. These anatomical and histological
mRNA expression profiles of oGPCRs provide useful clues about the physiological roles of oGPCRs in the GI tract. 相似文献
108.
Takeuchi T Nomura T Tsujita M Suzuki M Fuse T Mori H Mishina M 《Biochemical and biophysical research communications》2002,293(3):953-957
We constructed an expression vector of Flp recombinase modified by adding a nuclear localization signal. Injection of the expression vector into fertilized eggs of the C57BL/6 strain yielded transgenic mouse lines expressing the Flp recombinase transgene in the testis. We crossed the transgenic mice to reporter mice carrying the neomycin phosphotransferase gene flanked by target sites of Flp recombinase. Examination of the deletion of the neomycin phosphotransferase gene in the progeny showed that Flp-mediated recombination took place efficiently in vivo in FLP66 transgenic mouse line. These results suggest that the Flp recombinase system is effective in mice and in combination with the Cre recombinase system extends the potentials of gene manipulation in mice. One of the useful applications of FLP66 transgenic mouse line is the removal of marker genes from mice manipulated for the conditional gene targeting with the Cre/loxP system in the pure C57BL/6 genetic background. 相似文献
109.
Nobuo Terada Nobuhiko Ohno Hisashi Yamakawa Takeshi Baba Yasuhisa Fujii Zagreb Zea Osamu Ohara Shinichi Ohno 《The journal of histochemistry and cytochemistry》2004,52(6):769-777
Cell-cell adhesion is crucial not only for mechanical adhesion but also for tissue morphogenesis. Protein 4.1B, a member of the protein 4.1 family named from an erythrocyte membrane protein, is a potential organizer of an adherens system. In adult mouse seminiferous tubules, protein 4.1B localized in the basal compartment, especially in the attaching region of spermatogonia and Sertoli cells. Protein 4.1B localization and appearance were not different in each spermatogenic stage. Developmentally, protein 4.1B was not detected at postnatal day 3 (P3), was diffusely localized at P15, and was found in the basal compartment during the third week. By double staining for protein 4.1B and F-actin, their localizations were shown to be different, indicating that protein 4.1B was localized in a region lower than the basal ectoplasmic specialization that formed the Sertoli-Sertoli junction. By electron microscopy, immunoreactive products were seen mainly on the membranes of Sertoli cells. In the W/W(v) mutant mouse, the seminiferous epithelium had few germ cells. Protein 4.1B and beta-catenin were not detected, although the basal ectoplasmic specialization was retained. These results indicate that protein 4.1B may be related to the adhesion between Sertoli cells and germ cells, especially the spermatogonium. 相似文献
110.