- 學位論文
WRKY25與HDA6交互作用對於鹽分逆境反應及開花的影響
Effects of interaction of WRKY25 and HDA6 in salt stress response and flowering in Arabidopsis
摘要
WRKY轉錄因子在逆境下扮演重要的角色，也被報導與多種蛋白會有交互作用。WRKY為植物特有之轉錄因子，可透過與w-box結合活化或是抑制以調節下游基因表現，並對植物生理功能上做出相對應的反應。透過雙分子螢光互補實驗發現14-3-3w及HDA6對於WRKY25有交互作用，其功能還不明確。另外，為了瞭解HDA6上的磷酸化位點為何，我們也透過激酶活性分析發現其片段中三到四個位點對於磷酸化似乎有著其重要性。為了研究WRKY25與HDA6交互作用之功能為何，我們將hda6突變株 (hda6-6) 與WRKY25大量表現株進行雜交。在鹽處理下，WRKY25大量表現株與35S:WRKY25/hda6-6與野生型相比有較高的生存率，hda6-6則是對野生型有相對低的生存率，表示35S:WRKY25/hda6-6抗鹽的表現型貢獻自WRKY25。另外我們也針對開花時間進行測試。過去文獻中發現hda6-6有晚開花的現象，而在實驗中發現WRKY25大量表現株會有早開花的現象，而35S:WRKY25/hda6-6則是介於兩者之間，表示大量表現WRKY25似乎能部分互補hda6-6對於開花的功能，使其開花時間提前發生。另外，也針對WRKY25潛在的磷酸化位點進行突變，我們發現到似乎WRKY25 第345號蘇胺酸為14-3-3w與WRKY25結合位，並且第345號蘇胺酸點突變株在鹽逆境下的生存率是有所差異的。綜合上述結果，阿拉伯芥中WRKY25可能透過與HDA6及14-3-3w之交互作用，並對於鹽分逆境與開花上有所調控。
並列摘要
WRKY transcription factors play important roles in salt stress response, and it also has been reported that WRKYs interacted with many proteins. WRKYs are plant-specific transcription factors. WRKYs can bind to the W-box to activate or repress downstream genes to affect plant physiological functions. We found that WRKY25 could interact with HDA6 and 14-3-3w by bimolecular fluorescence complementation (BiFC) assays, but the functions of HDA6 and 14-3-3w proteins interacting with WRKY25 are still not clear. Moreover, we identified three or four specific amino acids in HDA6 are phosphorylated by calcium-dependent protein kinase 16 (CDPK16) in in vitro kinase assays. To identify the function of WRKY25 interacting with HDA6, we crossed the WRKY25 overexpression line and hda6 mutant (hda6-6). WRKY25 overexpression lines and 35S:WRKY25/hda6-6 exhibited higher tolerance to salt stress in survival rate, but hda6-6 was more sensitive to salt stress. It seemed that the phenotype of 35S:WRKY25/hda6-6 to salt stress was contributed by WRKY25. In addition, we also examined the flowering time phenotype. In previous studies, hda6-6 has a delayed flowering phenotype. We found that WRKY25 overexpression lines showed an early flowering phenotype, and 35S:WRKY25/hda6-6 was between both. It represented that WRKY25 might partially complement hda6-6 on flowering phenotype. We also pointed mutated WRKY25 potential phosphorylated sites. We found that Tyrosine-345 of WRKY25 might be an interacting site with 14-3-3w, and it might affect survival rate under salt stress condition. Taken together, WRKY25 might interact with HDA6 and 14-3-3w, and it affected salt stress responses and flowering in Arabidopsis.
參考文獻
延伸閱讀
- YEH, C. Y. (2016). 大量表現阿拉伯芥WRKY25基因影響鹽分逆境反應與生長發育 [master's thesis, National Taiwan University]. Airiti Library. https://doi.org/10.6342/NTU201600221
- 王經文、翁韶良、廖天賜、陳明男、陳忠義（2020）。水筆仔苗木於不同鹽度處理下光合誘導反應之探討。林業研究季刊，42(2)，91-104。https://www.airitilibrary.com/Article/Detail?DocID=16068351-202006-202008260010-202008260010-91-104
- 林庭弘（2009）。利用銨鹽突變株探討植物氮利用與光合作用之交互調控〔碩士論文，國立臺灣大學〕。華藝線上圖書館。https://doi.org/10.6342/NTU.2009.01359
- Wang, M. S. (2016). 阿拉伯芥HMGB15蛋白與組蛋白去乙醯化酶HDA6互作參與開花調控之研究 [master's thesis, National Taiwan University]. Airiti Library. https://doi.org/10.6342/NTU201600766
- Shih, W. T. (2015). Functional analysis of Arabidopsis WRKY63 in salt stress response and flowering time control [master's thesis, National Taiwan University]. Airiti Library. https://doi.org/10.6342/NTU.2015.00539