阿拉伯芥EAR蛋白ZFP11與去乙醯化酵素交互作用之功能研究

Function of EAR domain protein ZFP11 and its interaction with histone deacetylases in Arabidopsis thaliana

吳玟琳(Wen-Lin Wu)

指導教授 ： 吳克強

國立臺灣大學/生命科學院/植物科學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.00175

摘要

植物遭遇逆境時利用調控分子及細胞層級來適應環境，轉錄調控基因的表現是植物用來適應環境刺激的基本機制。在部分阿拉伯芥ERF蛋白及SUPERMAN蛋白裡，有一段保守的蛋白質模組L/FDLNL/F(x) P，被稱為EAR(ERF-associated amphiphilic repression)，其作用是參與轉錄抑制因子的功能。本研究中我們進行了SUPERMAN 蛋白ZFP11的功能性研究。研究中發現ZFP11轉錄因子的細胞定位在細胞核裡。我們利用雙分子螢光複合物分析(BiFC)研究結果顯示，ZFP11蛋白會與去乙醯化酵素HDA6及HDA19 有蛋白質交互作用，我們更進一步的發現，ZFP11利用其鋅指結構基元(Zinc Finger Motif)來進行蛋白質之間的互作。zfp11突變株帶有一個胺基酸的突變，正好突變在鋅指結構基元上。此突變株有較野生型小的型態，且開花時間較野生型早，顯示鋅指結構基元對ZFP11的正常功能非常重要。另外zfp11突變株在種子萌發的階段對離層素及鹽逆境下跟野生型比較下較為敏感，且經過離層素處理後zfp11突變株會減少對離層素反應的基因ABI1和ABI2的表現。這些實驗結果顯示ZFP11在離層素及鹽的下游反應中扮演了重要的角色。

關鍵字

阿拉伯芥 ； 逆境反應 ； 轉錄因子 ； EAR蛋白模組 ； ZFP11 ； 去乙醯化酵素

並列摘要

Plants respond and adapt to stresses under stress conditions at the molecular and cellular levels. Transcriptional regulation of gene expression plays a fundamental role in response to environmental stimuli. A conserved sequence motif L/FDLNL/F(x) P was identified from the ERF proteins and SUPERMAN proteins that act as transcription repressors in Arabidopsis. This motif was named as the ERF-associated amphiphilic repression (EAR) motif, which was found to be essential for gene repression. In this study, the function of the SUPERMAN protein ZFP11 was investigated. It was found that ZFP11 was localized in the nucleus. ZFP11 can interact with HDA6 and HDA19 directly and the N-terminal of ZFP11 containing the zinc finger motif was responsible for the interaction. The zfp11 mutant carries a point mutation that changes one amino acid on the zinc finger motif of ZFP11. The zfp11 mutant plants displayed a dwarf and early flowering phenotype, suggesting that the zinc finger motif is important for the function of ZFP11. Compared with the wild-type, the zfp11 mutant plants show hypersensitive to ABA and NaCl in seed germination. Furthermore, the expression of ABI1 and ABI2 was decreased in the zfp11 mutant plants. These data suggested that ZFP11 may play an important role in plant ABA and salt responsive pathways.

並列關鍵字

Arabidopsis thaliana ； stress response ； transcription factor ； EAR domain ； ZFP11 ； HDACs

參考文獻

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