劉麗飛2006-08-232018-07-112006-08-232018-07-111998-07-31http://ntur.lib.ntu.edu.tw//handle/246246/29653植物細胞具分化全能性，亦即可 經由培養條件的調整，使單一細胞再 生為完整植株。惟至目前為止，對此 分化全能性機制的了解仍極有限。本 計畫曾以水稻培養細胞為材料，探討 滲透壓誘導植株再生過程中碳水化合 物代謝之角色。本研究室其他的研 究，也已證明在水稻的細胞培養系統 中，滲透壓會提高細胞內 IAA、ABA 之含量。此兩者之變化均與植株再生 有密切相關。因此，本試驗乃進一步 探討內生植物荷爾蒙與碳水化合物代 謝，在滲透壓誘導水稻癒合組織植株 再生過程中的角色。試驗結果發現， 台南5 號未成熟胚在同時含有IAA 合 成前驅物 anthranilic acid 及 ABA 的 MSD10 培養基中誘導之癒合組織 (TN5-AnA)，其生長明顯減緩，細胞內 水分含量及水勢、滲透勢也明顯低於 沒有外加植物荷爾蒙處理者 (TN5)； 將此癒合組織移入分化培養基後，可 大幅提高植株再分化能力，此現象與 高濃度滲透壓處理者相符。此外， TN5-AnA 在癒合組織誘導階段，細胞 內可溶性糖與澱粉含量均顯著高於 TN5 處理者，上述結果暗示，外加植 物荷爾蒙處理，似乎可取代高濃度滲 透壓處理，影響水稻癒合組織中內生 植物荷爾蒙與碳水化合物之代謝，誘 導植株之再生。因此推測，高濃度滲 透壓處理可能導致細胞內 IAA 及 ABA 含量提高，藉由這兩種植物荷爾 蒙作為訊息傳導因子，調控碳水化合 物之代謝，進一步影響植株之再生。 本研究將再進一步分析此外加植物荷 爾蒙處理者，其碳水化合物代謝相關 酵素之活性與蛋白質表現情形。Plant cells possess totipotency that means whole plants could be regenerated from single cell by modulating culture conditions. The mechanisms of totipotency, however, were limitedly understood so far. The purpose of this project is to explore the possible roles of carbohydrate metabolism in osmotic-stressed rice callus during shoot regeneration. After thorough studies, we already got good understanding of the changes of soluble sugars, starch, and the enzymes related to sugar and starch metabolisms. From the other study in our lab, it had found the contents of endogenous IAA and ABA were increased significantly in rice callus by osmotic stress treatment, and were correlated to the ability of shoot regeneration. We, therefore, did further studies to explore the correlation among phytohormones, carbohydrate metabolism and osmotic stress during shoot regeneration. Two Kinds of callus were used in the studies. TN5 callus was induced on MSD10 basal medium and used as control. TN5-AnA callus was induced on MSD10 basal medium containing 2mM anthranilic acid and 100μM ABA. The results showed that during callus induction stage, TN5-AnA callus has lower callus growth rate, cellular water content, water potential, and osmotic potential than TN5 callus. After being transferred to regeneration medium, TN5-AnA showed prosperous shoot regeneration. Besides, both soluble sugars and starch contents are prominently higher in TN5-AnA callus. All these phenomenon in TN5-AnA callus are similar to those in osmoticstressed callus. It proved that the osmotic stress could be replaced with the treatment of exogenous phytohormones to induce shoot regeneration feature. Therefore, we proposed that osmotic stress might affect the contents of endogenous IAA and ABA which serve as signals to regulate carbohydrate metabolism, and finally cause the shoot regeneration of rice callus.application/pdf37440 bytesapplication/pdfzh-TW國立臺灣大學農藝學系暨研究所碳水化合物代謝水稻組 織培養滲透壓逆境carbohydrate metabolismricetissue cultureosmotic stressreporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/29653/1/872313B002102A06.pdf