請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/49126
標題: | 利用阿拉伯芥進行日日春 NPR1 與 NPR3 基因之功能分析 Functional analysis of CrNPR1 and CrNPR3 in Arabidopsis thaliana |
作者: | Yu-Ling Chen 陳鈺凌 |
指導教授: | 林長平 |
共同指導教授: | 陳仁治 |
關鍵字: | 系統性抗病,水楊酸,日日春,阿拉伯芥,NPR1,NPR3, SAR,SA,periwinkle,Arabidopsis,NPR1,NPR3, |
出版年 : | 2016 |
學位: | 碩士 |
摘要: | 植物菌質體 (phytoplasma) 為不具細胞壁寄生於植物韌皮部之細菌。它能透過媒介昆蟲傳播,在多種經濟作物上造成病害。而植物則可能利用系統抗病對抗植物菌質體的感染。當日日春受日日春葉片黃化病 (periwinkle leaf yellowing, PLY ) 植物菌質體感染時,PR1基因的表現在有病徵及無病徵枝條中皆被誘導,且無病徵枝條有較佳的日日春葉片黃化病的抗性。NPR1與NPR3為系統抗病 (Systemic-acquired resistance,SAR) 途徑之重要基因。受PLY植物菌質體感染的日日春,其CrNPR1基因表現趨勢與CrPR1a相似,且基因靜默CrNPR1會使CrPR1a基因表現量下降,亦加速日日春葉片黃化病的病程發展。而CrNPR3靜默植株則病程發展較為遲緩。為進一步了解CrNPR1與CrNPR3與他們在阿拉伯芥中的同源基因AtNPR1在抗病功能上是否相似,本研究在阿拉伯芥的Col-0 、 NPR1突變株npr1-1及水楊酸含量低的NahG (SA hydroxylase) 轉殖株上分別大量表現AtNPR1、CrNPR1與CrNPR3,並比較它們對Pseudomonas syringae pv. tomato DC3000 (PstDC3000) 的抗性反應。結果不論NahG轉殖株大量表現AtNPR1、CrNPR1或CrNPR3,皆無法回復植株在感染後PR1的誘導。因此與AtNPR1相似CrNPR1及CrNPR3所調控的抗病途徑可能需要水楊酸。 而大量表現CrNPR1於npr1-1,AtPR1看似有些微的誘導表現,未來需要更多的材料進行實驗確認結果。然而在菌量累積的分析上由於無法觀察到轉基因有增強Col-0或回復npr1-1的抗病反應,因此尚無法確認CrNPR1及CrNPR3的功能是否與AtNPR1相似。未來將嘗試以不同的轉殖系統再進行接種試驗以確認結果,並探討 CrNPR1與CrNPR3是否與AtNPR1功能相同皆須透過SA的誘導進入細胞核中作用。此外因菌量累積分析顯示, NahG及npr1-1與Col-0相比無明顯的較為感病,因此未來需再改善接種試驗的流程。希望透過本研究藉此釐清日日春抗植物菌質體之感染所誘導的抗病反應。 Phytoplasmas, wall-less and phloem-restricted plant pathogens, are transmitted by insect vectors. They can infect many crops and cause severe symptoms. Plant may use a systemic defense system to fight against them. In periwinkles, PR1 is induced in both symptomatic and non-symptomatic parts when they are infected by PLY phytoplasma, and the non-symptomatic parts are more resistant to PLY phytoplasma infection than healthy controls. Both NPR1 and NPR3 play an important role in Systemic acquired resistance (SAR). When periwinkles are infected by PLY, CrNPR1 is moderately induced. In addition, silencing of CrNPR1 accelerates symptom progression of PLY, while silencing of CrNPR3 attenuates the progression. To further understand whether the functions of CrNPR1 and CrNPR3 are similar to their Arabidopsis homolog, AtNPR1, we generated Arabidopsis transgenic plants that overexpress AtNPR1, CrNPR1 or CrNPR3 in Col-0, npr1-1 and NahG backgrounds, and compared their defense responses to Pseudomonas syringae pv. tomato DC3000 (PstDC3000). The results showed that induction of PR1 was not restored after PstDC3000 infection in all transgenic lines in the NahG background, indicating that similar to AtNPR1, induction of PR1 mediated by CrNPR1 or CrNPR3 may depend on SA signaling. In addition, overexpressed CrNPR1 in npr1-1 seems to slightly restored the induction of PR1 expression; however, we need to repeat the experiment to confirm the results. We also did not observe the restored plant defense to PstDC3000 in all of the transgenic lines. Therefore, we failed to conclude whether CrNPR1 and CrNPR3 have a similar function to AtNPR1 to affect disease resistance of Arabidopsis to PstDC3000. In addition, NahG and npr1-1 lines were not more susceptible to Pst DC3000 infection than Col-0. The experimental conditions will need to be optimized to obtain consistent results, and the function of CrNPR1 and CrNPR3 will be concluded in the future. Because AtNPR1 enters nucleus in response to SA, the localization of CrNPR1 and CrNPR3 will also be examined in the future. Our results will extend our knowledge in plant defense mechanism against phytoplasma. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/49126 |
DOI: | 10.6342/NTU201603188 |
全文授權: | 有償授權 |
顯示於系所單位: | 植物病理與微生物學系 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-105-1.pdf 目前未授權公開取用 | 3.08 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。