著者

三島 鮎美 高橋 裕美 奥 尚枝 松野 純男 十万 佐知子 中林 利克 石黒 京子

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集 47 (ISSN:24331856)

巻号頁・発行日

pp.541-546, 2005-09-15 (Released:2017-08-18)

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The petal of Hibiscus mutabilis L. f. versicolor MAKINO shows a white color after the flowering, and it gradually changes in the red. Though it is reported that the color changes are due to the storage of the anthocyanin in the petal vacuole, the mechanism has not been clarified. Thus, the mechanism of the color change was elucidated by expression analysis of mRNA of anthocyanidin synthetase (ANS) in the petal. Extraction and purification of mRNA: petals of white, pink and red organization of freezed fresh H. mutabilis were crushed in the liquid nitrogen and total RNA was extracted using the CTAB method, followed by the refinement of each mRNA by Purification Kit (TaKaRa). The several kinds of primer of actin and ANS were designed from the homology with other plants respectively and then RT-PCR was done using these primers. On cDNA fragment amplified by RT-PCR, the base sequence was analyzed by the conventional mannner. Using the primer which efficiently amplified the cDNA fragment, the expression of mRNA of the ANS with the change of the flower color was examined by RT-PCR. The amplified fragment of about 600bps was assigned to that of actin and the amplified fragment of about 500bps expressed only in the deep red petal was assigned to that of the ANS of H. mutabilis, referring to the sequence of actin and the ANS respectively. The amino acid sequence of mRNA of actin of H. mutabilis showed a homology over 91% with those of the other type plant and that of the ANS showed a homology over 82%. The expression level of mRNA of the ANS was consistent with the increase in the deep red from the white color. Furthermore, the color change was dependent on temperature but not the light.

著者

安元 剛 西上 明則 岡田 泰宏 楠見 武徳 大井 高 安元 美奈 笠井 文絵

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集 47 (ISSN:24331856)

巻号頁・発行日

pp.205-210, 2005-09-15 (Released:2017-08-18)

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It has been known that some aquatic organisms change their morphology to defend themselves in response to kairomones released from their predators, although very few kairomones are chemically identified. Scenedesmus, unicellular fresh-water phytoplankton, forms colonies in the presence of its grazer, Daphnia. Hessen and van Donk (1993) discovered the involvement of a chemical substance released from the Daphnia in stimulation of colonies. The addition of filtered medium from a Daphnia magna culture to unicellular Scenedesmus subspicatus achieved within a few days morphological change into 2-, 4-, and 8-colonies, while the controls remained unicellular. Their report has aroused the interest of many scientists to attempt to identify the kairomone, but the chemical substance that triggers this behavior has not been identified. Here we report the identification of the Daphnia kairomones as aliphatic sulfates that cause the morphological change in a unicellular green alga Scenedesmus gutwinskii var. heterospina (NIES-802) at 0.1-1000ng/ml concentrations. The kairomones were synthesized to rule out the possibility that the isolated substances are inactive and they might still be contaminated with a minute amount of 'super active compound'.