水稻轉錄因子OsERF106負向調控水稻鹽逆境耐受性

Rice Transcription Factor OsERF106 Plays a Negative Role in Salt Stress Tolerance

簡梓丞(Tzu-Cheng Chien)

指導教授 ： 張孟基

國立臺灣大學/生物資源暨農學院/農藝學研究所/碩士(2018年)

https://doi.org/10.6342/NTU201803621

摘要

水稻轉錄因子Ethylene Responsive Factors (OsERFs) 為一多基因家族，參與植物生長、發育和逆境反應。根據已發表DNA微陣列 (Microarray) 和即時定量PCR資料顯示OsERF106受鹽逆境誘導，然而OsERF106於鹽逆境中功能尚未明瞭。本篇研究利用反向遺傳學 (Reverse genetics) 方法，探討OsERF106於鹽逆境中所扮演之角色。我們使用Rapid Amplification of cDNA Ends (RACE) 選殖OsERF106，結果顯示編碼序列 (Coding sequence) 共有648個核苷酸。OsERF106過量表現株在正常環境下較為矮小，且鹽逆境耐受性較低，進一步分析顯示過量表現OsERF106會降低水稻過氧化氫酶活性，並累積較多活性氧族 (Reactive oxygen species, ROS)。此外過量表現OsERF106會增加OsSOS1及降低OsHKT1;4離子通道蛋白表現量，導致鹽逆境中地上部累積較多鈉離子和鉀離子。轉錄體分析結果顯示鹽逆境下過量表現OsERF106會降低離子通道蛋白OsHKT1;4和逆境相關轉錄因子OsbZIP16、OsWRKY42、OsWRKY45表現，並提高鉀離子轉運蛋白OsTPKb、OsHAK12及氯離子轉運蛋白OsCCC1表現。綜上所述，OsERF106可能參與水稻生長和鹽逆境耐受性，並扮演負向調控之角色。

關鍵字

轉錄因子 ； OsERF106 ； RACE ； 鹽逆境 ； 活化氧族 ； 離子通道蛋白基因 ； 轉錄體分析

並列摘要

Rice Ethylene Responsive Factors (OsERFs) belong to a large gene family can impact plant growth, development and stress responses. Analysis of public microarray data and qPCR analysis indicated that the expression of OsERF106 was up-regulated under salinity stress. However, the function of OsERF106 under salt stress is still unknown and remain to be elucidated. In this study, we used reverse genetic approach to characterize the function of OsERF106 in the salt stress. First, we clone the full open reading frame of OsERF106 gene by Rapid Amplification of cDNA Ends (RACE). The result shows the coding sequence length of OsERF106 is 648 base pair. The OsERF106-overexpressing transgenic rice displayed retarded growth with a high level of reactive oxygen species and significantly decreased antioxidant enzyme activity, especially under salt stress. Moreover, the OsERF106-overexpressing line increased the expression level of ion transporter OsSOS1 and decreased OsHKT1; 4 gene expression, resulted in higher Na+ and K+ accumulation in rice shoots. The transcriptome analysis showed that OsERF106 down-regulated the gene expression levels of OsHKT1; 4 and stress-related transcription factors OsbZIP16, OsWRKY42, OsWRKY45, while the gene expression of potassium transporters OsTPKb, OsHAK12 and chloride transporter OsCCC1 were up-regulated. Taken together, OsERF106 plays a negative role in regulating plant growth and salt stress tolerance.

並列關鍵字

Transcription factor ； OsERF106 ； RACE ； Salt stress ； Reactive oxygen species ； Ion transporter gene ； Transcriptome analysis.

參考文獻

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