Please use this identifier to cite or link to this item:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/76605
Title: | 受一氧化碳抑制的嶄新miRNA-tag1780參與在甘藷台農57號傷害逆境的反應 A carbon monoxide down regulated novel miRNA-tag1780 in sweet potato (Ipomoea batatas cv. Tainung 57) under wounding |
Authors: | Sheng-Yuan Hsieh 謝昇原 |
Advisor: | 鄭石通(Shih-Tong Jeng) |
Keyword: | 甘藷,一氧化碳,傷害逆境,嶄新miRNA,綠原酸, sweet potato,carbon monoxide,wounding,novel miRNA,3-dehydroquinate dehydratase/shikimate dehydrogenase(DQD/SDH),quinate,chlorogenic acid, |
Publication Year : | 2017 |
Degree: | 碩士 |
Abstract: | miRNA會調控植物體的生長和逆境反應。而一氧化碳(CO)在植物體內扮演著訊號分子的角色,同樣會參與植物的生長發育和對逆境反應下的調控。但是,目前尚未知道是否CO會透過miRNA去調控植物的生長發育和對逆境下的反應。因此,此研究透過建立了CO處理和未經CO處理的small RNA sequencing資料庫進行比對分析找出跟CO相關的miRNA。small RNA sequencing顯示嶄新的miRNA tag1780可能會受CO所調控。除此之外, 不論是precursor form tag1780 (pre-tag1780)或者mature from tag1780(tag1780)的表現量都會受5% CO水溶液所抑制。同樣對pre-tag1780 及tag1780去探討在傷害處理下表現量的變化。結果顯示tag1780會受傷害處理所誘導。有趣的是,在同時處理傷害和CO的情形下,CO會將傷害處理所誘導的tag1780表現量給消弭掉。根據tag1780和目標mRNA互補性序列的關係,從transcriptome資料庫中找出3個可能會受到tag1780所調控的基因序列。其中一個目標基因3-dehydroquinate dehydratase/shikimate dehydrogenase (DQD/SDH)在傷害處理下,和tag1780的表現量有著相反的趨勢,並且以5’RLM-RACE分析發現tag1780會辨認DQD/SDH,並且在tag1780第11和第12個核苷酸中間切割DQD/SDH。再者,在利用甘藷大量表現pre-tag1780的轉殖株中,發現DQD/SDH gene表現量被抑制,因此推論DQD/SDH 可能會受到tag1780所調控。DQD/SDH是shikimate pathway其中一個酵素,並且是決定要合成dehydroshikimate、shikimate或quinate 很重要的分岔點。推論甘藷在傷害前期下,甘藷透過抑制DQD/SDH,使甘藷不合成dehydroshikimate及shikimate,而選擇去合成quinate。而quinate是合成綠原酸(chlorogenic acid)的前驅物,進而使得綠原酸含量提升。經由實驗證實在傷害處理後,綠原酸含量確實有隨傷害而增加。總結,甘藷在傷害前期,會透過抑制一氧化碳含量來誘導嶄新miRNA-tag1780,而被tag1780所調控的DQD/SDH gene則會在傷害逆境下被抑制,造成綠原酸含量提升,並透過綠原酸來達到植物防禦的功能。 MicroRNAs (miRNAs) regulate plant growth and stress responses. Carbon monoxide (CO) is also a signaling molecule participating in plant growth and stress responses. However, it is still unknown whether CO regulates plant development and stress responses through miRNA. Small RNA deep sequencings of CO-treated and non-treated sweet potato were performed to identify CO-related miRNAs. Deep sequencing data showed the expression level of novel miRNA tag1780 might be affected by CO. In addition, the expression levels of precursor form tag1780 (pre-tag1780) and mature form tag1780 (tag1780) were down-regulated by 5% CO solution. Moreover, pre-tag1780 and tag1780 expression was also analyzed in sweet potato leaves with or without wounding. Results revealed that tag1780 was wounding-induced. Interestingly, the wounding-induced effect of tag1780 was attenuated by CO. According to the complementary between tag1780 and target mRNA, three putative target genes were obtained from transcriptome database. 3-dehydroquinate dehydratase/shikimate dehydrogenase (DQD/SDH), one of the putative tag1780 targets, showed the reverse expression pattern compared to tag1780 under wounding response. In addition, 5’RLM-RACE showed the cleavage site induced by tag1780 in DQD/SDH was located between 11th and 12th nucleotide relative to tag1780. Furthermore, the gene expression level of DQD/SDH was repressed in the transgenic sweet potatoes overexpressing pre-tag1780. Therefore, DQD/SDH was the target of tag1780. In fact, DQD/SDH is one of the enzyme participating in shikimate pathway, which leads to the synthesis of dehydroshikimate, shikimate, and quinate. It would be possible that when sweet potato is under wounding, it might synthesize quinate, a precursor of chlorogenic acid, rather than dehydroshikimate or shikimate in order to increase the content of chlorogenic acid. Furhter experiment indicated that the quantity of chlorogenic acid in sweet potato upon wounding was indeed increased. Conclusively, sweet potatoes induced the production of novel miRNA tag1780 by reducing endogenous CO content, and tag1780’s target DQD/SDH gene was repressed in order to increase the chlorogenic aicd to cope with early wounding stress. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/76605 |
DOI: | 10.6342/NTU201700520 |
Fulltext Rights: | 未授權 |
Appears in Collections: | 植物科學研究所 |
Files in This Item:
File | Size | Format | |
---|---|---|---|
ntu-106-R03B42027-1.pdf Restricted Access | 2.51 MB | Adobe PDF |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.