46 ブラシノステロイド生合成阻害剤(Brz)処理によって生じる形態変化の顕微鏡学的解析

概要

論文の詳細を見る
When the brassinosteroid biosynthesis inhibitor (Brz) was exogenously applied to 1/2 MS medium at a concentration of 0.1-2μM, Arabidopsis seedlings in the dark exhibited photomorphogenesis, such as inhibition of cell elongation in hypocotyls, expansion of cotyledons, development of true leaves. At 40 days after sowing in the dark of 2μM Brz, significant expansion of several rosette leaves was observed. For the analysis of DNA synthesis, BrdU (an analogue of thymidine) was applied to seedlings in the dark at 8-10 days after sowing. Many nuclei in the shoot apical meristem in the dark were labeled with BrdU in Brz-treated seedling, while less nuclei were labeled in non-treated seedling. The activation of DNA synthesis n shoot apical meristems was shown by treatment with Brz. We examined plastid morphology in cotyledons in dark grown seedlings by electron microscopy. They were typical etioplast, that is absence of thylakoid membranes, in both Brz-treated and non-treated cotyledons. In Brz-treatment, the lack of diggerentiation of etiplasts to chloroplasts was suggested. However, Immunoblot analyses and immunostaining revealed that the accumulated levels of Rubisco protein in Brz-treated seedlings were much higher that non-treated seedlings. These results suggested that Brz exhibits photomorphogenesis in the dark to some extent.
植物化学調節学会の論文
1999-10-01