2019-01-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/671848摘要：鋅是人體必需的微量營養元素之一，然而世界上有三分之一的人口為鋅攝取不足的危險群，特別是在以水稻為主食的地區。與其他糧食作物相比，水稻的含鋅量偏低，因此針對水稻進行鋅的生物營養強化(Biofortification)是解決人體鋅攝取不足的有效方式。要進行鋅的生物營養強化，首先必須了解水稻中調控鋅含量之分子機制。在過去的研究發現：模式植物阿拉伯芥F群basic leucine zipper轉錄因子(FbZIPs)，bZIP19和bZIP23，可藉由與ZDRE (Zinc Deficiency Response Element)之結合，調控一系列鋅轉運蛋白的表達，進而調控鋅的吸收。本研究中，首先找到水稻（Oryza sativa L.）中的F-bZIP轉錄因子(F-OsbZIPs)，並測試它們與ZDRE結合的能力。接著進一步比較F-OsbZIPs基因及含ZDRE元件的基因（如：ZIP基因家族）在缺鋅下的表現量，藉以了解水稻如何感知外在鋅的狀態，及其在缺鋅下如何啟動鋅元素吸收之分子機制。我們亦將在水稻中建立F-OsbZIPs過量表達及利用CRISPR/Cas9基因編輯的抑制表達的轉殖系，比較其鋅元素運輸及累積之差異。此外，將更進一步的找到可與F-OsbZIPs結合，共同調控鋅平衡的轉錄因子，藉以了解OsbZIPs是如何參與及調控水稻中鋅元素的生理機制。期以此研究幫助選擇及創造適合進行水稻鋅生物營養強化的品種，並為鋅的生物營養強化提供可行的育種方向。<br> Abstract: Zinc (Zn) is an essential micronutrient, but one-third of the world’s population is at risk of Zn deficiency, especially in areas where rice is the staple food. The Zn content of rice grains is relatively low compared to other crops, and Zn biofortification has therefore been investigated as a strategy to address Zn deficiency in populations that subsist on a rice-based diet. Effective biofortification requires an understanding of Zn homeostasis in rice. Recently, two F-group basic leucine zipper (F-bZIP) transcription factors (bZIP19 and bZIP23) in the model plant Arabidopsis thaliana were shown to regulate the expression of metal transporter genes in response to Zn limitation by binding to zinc deficiency response elements (ZDREs) in the promoter regions of metal transporter genes. In the proposed project, we will first characterize the homologous F-bZIP proteins in rice (Oryza sativa L.) and test their ability to bind ZDREs. To understand the molecular basis of Zn sensing and responses to Zn limitation, we will measure the expression of rice F-bZIPs and ZDRE-containing genes such as the ZIP (Zrt/Irt-like Protein) family under normal and Zn limiting conditions. We will also create transgenic rice plants in which the F-bZIP genes are overexpressed or knocked out by CRISPR/Cas9 genome-editing, and will compare them in terms of Zn transportation and accumulation. The interaction partners of F-bZIPs in rice will be characterized as well. Our work will provide the data necessary to understand how rice plants respond to Zn deficiency and will facilitate the development of effective biofortification strategies.zincricebiofortificationtransporterbasic leucine zipper鋅水稻轉錄因子轉運蛋白生物營養強化