Publications by authors named "Shigehisa Okamoto"

Methylthioacetic acid (MTA) is an acid-hydrolyzed derivative of a natural aroma compound, methylthioacetic acid ethyl ester isolated from Cucumis melo var. conomon (Katsura-uri, Japanese Picking Melon), and induces a villiform-like structure dome in RCM-1 human colorectal cancer cell culture. Thus far, the physiological and molecular properties of MTA-mediated dome formation remain unknown.

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Article Synopsis
  • The study focuses on Southeast Asian mints, which are under-researched yet important in cooking and medicine, examining their genetic diversity and classification.
  • Researchers used simple sequence repeat (SSR) markers and leaf morphology to identify two distinct types of mints based on their leaf shape and venation patterns.
  • The findings led to the development of 12 SSR markers that allowed for refined classification of these mints into groups, helping to clarify the genetic relationships among known and unclassified mint species.
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Two key transcription factors (TFs) in brassinosteroid (BR) signaling BRASSINOSTEROID INSENSITIVE 1-EMS-SUPPRESSOR 1 (BES1) and BRASSINAZOLE RESISTANT 1 (BZR1), belong to a small family with four BES1/BZR1 homologs (BEH1-4). To date, in contrast to the wealth of knowledge regarding BES1 and BZR1, little is known about BEH1-4. Here, we show that was expressed preferentially in the roots and leaf margins including serrations, which was quite different from another member , and that BRs downregulated through a module containing GSK3-like kinases and BES1/BZR1 TFs, among which BES1, rather than BZR1, contributed to this process.

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Colorectal cancer was the third most commonly diagnosed malignant tumor and the fourth leading cause of cancer deaths worldwide in 2012. A human colorectal cancer cell line, RCM-1, was established from a colon cancer tissue diagnosed as a well-differentiated rectum adenocarcinoma. RCM-1 cells spontaneously form 'domes' (formerly designated 'ducts') resembling villiform structures.

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Piperitenone oxide, a major chemical constituent of the essential oil of spearmint, Mentha spicata, induces differentiation in human colon cancer RCM-1 cells. In this study, piperitenone oxide and trans-piperitenone dioxide were prepared as racemic forms by epoxidation of piperitenone. The relative configuration between two epoxides in piperitenone dioxide was determined to be trans by H NMR analysis and nuclear Overhauser effect spectroscopy (NOESY) in conjunction with density functional theory (DFT) calculations.

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The fruit of Katsura-uri (Japan's heirloom pickling melon, Cucumis melo var. conomon) possesses a fruity aroma and moderate sweetness. The fruit juice has potential to minimize human postprandial blood glucose levels.

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bHLH-type transcription factors-BRASSINOSTEROID INSENSITIVE 1-EMS-SUPPRESSOR 1 (BES1) and BRASSINAZOLE RESISTANT 1 (BZR1)-play key roles in brassinosteroid (BR) signaling. By contrast, the functions of the other four BES1/BZR1 homologs (BEH1-4) remain unknown. Here, we describe the detailed expression profiles of the / family genes.

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To examine the effects of 4-methylthio-3-butenyl isothiocyanate on esophageal carcinogenesis, male 6-week-old F344 rats were subcutaneously injected with 0.5 mg/kg body weight -nitrosomethylbenzylamine three times per week for 5 weeks and fed a diet supplemented with 80 ppm 4-methylthio-3-butenyl isothiocyanate, equivalent to 6.05 mg/kg body weight/day for the initiation stage, 4.

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We recently reported that 4-methylthio-3-butenyl isothiocyanate (MTBITC) exerts chemopreventive effects on the rat esophageal carcinogenesis model at a low dose of 80 ppm in a diet. In contrast, some isothiocyanates (ITCs) have been reported to cause toxic effects, promotion activity, and/or carcinogenic potential in the urinary bladder of rats. In the present study, we investigated whether MTBITC had toxic effects in the urinary bladder similar to other ITCs, such as phenethyl ITC (PEITC).

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Brassinosteroids (BRs), a class of phytohormones, control various physiological and developmental processes in plants. Two highly homologous transcription factors, brassinosteroid insensitive 1-EMS-SUPRESSOR 1 (BES1) and brassinazole resistant 1 (BZR1), act downstream of BR signaling to control several thousands of putative target genes. We reported previously that BES1 forms a complex with a molecular chaperone: heat shock protein 90 (HSP90).

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Key Message: A closer association of HSP90s with brassinosteroid signaling is suggested by the brassinosteroid-triggered formation of an HSP90-containing macromolecular complex and the direct interaction between HSP90.3 and BES1.

Abstract: Heat shock protein 90 (HSP90) is a highly conserved molecular chaperone that is reportedly involved in the proper folding, stabilization, intracellular trafficking, maintenance and degradation of numerous proteins, as well as the facilitation of cellular signaling in various organisms including plants.

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The modifying effects of 4-methylthio-3-butenyl isothiocyanate (MTBITC) and curcumin were investigated in N-nitrosobis(2-oxopropyl)amine (BOP)-initiated hamsters. Male 6-week-old Syrian hamsters were subcutaneously injected with 10 mg/kg body weight (b.w.

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Aim: Adenomyosis patients treated with dienogest are considered to be at higher risk of uterine bleeding; however, the mechanisms which cause severe uterine bleeding in those patients are unknown. This study aims to investigate the risk factors of uterine bleeding among adenomyosis patients treated with dienogest.

Material And Methods: Clinical data of 51 adenomyosis patients treated with dienogest were retrospectively collected from their medical records.

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The phytohormone brassinosteroid (BR) is crucial for plant growth and development. Although genetic and molecular approaches have improved understanding of the cellular BR signaling pathway, we still do not have sufficient knowledge about the function of BR. Therefore, proteomic analysis was used to elucidate BR signaling and gene expression in the nuclei of suspended Arabidopsis cells treated with brassinolide, a bioactive BR, or brassinazole, a BR biosynthesis inhibitor.

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The expression of DWARF4 (DWF4), which encodes a C-22 hydroxylase, is crucial for brassinosteroid (BR) biosynthesis and for the feedback control of endogenous BR levels. To advance our knowledge of BRs, we examined the effects of different plant hormones on DWF4 transcription in Arabidopsis thaliana. Semi-quantitative reverse-transcriptase PCR showed that the amount of the DWF4 mRNA precursor either decreased or increased, similarly with its mature form, in response to an exogenously applied bioactive BR, brassinolide (BL), and a BR biosynthesis inhibitor, brassinazole (Brz), respectively.

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To identify nuclear proteins involved in the brassinosteroid (BR) signaling pathway, a targeted proteomic approach was applied to Arabidopsis thaliana suspension-cultured T87 cells. Cell growth was promoted by 0.1 μM brassinolide (BL) and inhibited by 5 μM brassinazole (Brz).

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Six fragrant ingredients were identified in fully-ripened Katsura-uri (Japanese pickling melon; Cucumis melo var. conomon). Four of them were sulfur-containing compounds [methylthioacetic acid ethyl ester (MTAE), acetic acid 2-methylthio ethyl ester (AMTE), 3-methylthiopropionic acid ethyl ester (MTPE), and acetic acid 3-methylthio propyl ester (AMTP)]; and the others were benzyl acetate and eugenol.

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The fully ripened fruit of Katsura-uri Japanese pickling melon ( Cucumis melo var. conomon) has rarely been used for food because the midripened fruit is utilized for making pickles, but the fully ripened fruit is no longer valuable for pickles due to the fruit body being too soft. We have considered the utilization of the fully ripened Katsura-uri fruit that may be used for nonpickling products, particularly if the fully ripened fruit demonstrated health benefits such as anticarcinogenic properties.

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Myrosinase is a cytosolic plant enzyme present in daikon ( Raphanus sativus, Japanese white radish) roots that hydrolyzes 4-methylthio-3-butenyl glucosinolate (MTBGLS) into the natural pungent agent 4-methylthio-3-butenyl isothiocyanate (MTBITC), which possesses antimicrobial, antimutagenic, and anticarcinogenic properties. The concentration of MTBGLS, myrosinase activity, and production of MTBITC in seven daikon varieties (one conventional and six heirlooms) were determined to rank the activity of the glucosinolate-myrosinase system and identify critical factors influencing the production of MTBITC. The six heirloom varieties produced 2.

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An electro-elution procedure has been employed efficiently to collect proteins from stem segments, young leaves and roots of the Japanese morning glory. Electrophoretic conditions were optimised, including the size of segments (10-30 mm), the strength of the current for electro-elution (2.5-10 mA), and the exposure time of electro-elution (2-12 h).

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Homeostasis of brassinosteroids (BRs) is essential for normal growth and development in higher plants. We examined responsiveness of 11 BR metabolic gene expressions to the decrease or increase of endogenous BR contents in Arabidopsis (Arabidopsis thaliana) to expand our knowledge of molecular mechanisms underlying BR homeostasis. Five BR-specific biosynthesis genes (DET2, DWF4, CPD, BR6ox1, and ROT3) and two sterol biosynthesis genes (FK and DWF5) were up-regulated in BR-depleted wild-type plants grown under brassinazole, a BR biosynthesis inhibitor.

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