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完整後設資料紀錄
DC 欄位 | 值 | 語言 |
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dc.contributor.advisor | 楊淑怡(Shu-Yi Yang) | |
dc.contributor.author | Yu-Heng Hsieh | en |
dc.contributor.author | 謝於恆 | zh_TW |
dc.date.accessioned | 2021-06-08T03:34:52Z | - |
dc.date.copyright | 2021-02-22 | |
dc.date.issued | 2021 | |
dc.date.submitted | 2021-01-27 | |
dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/21465 | - |
dc.description.abstract | 前人發現,當植物與土壤中有益真菌-叢枝菌根菌(Arbuscular mycorrhizal fungi)共生時,植物可發展出較多的側根,同時,根部可累積較多磷及生長素(Auxin)。雖然前人推測磷和生長素對於菌根菌促進側根生長的過程中或許扮演重要角色,其詳細的分子機制仍然未知。我們發現,番茄和叢枝菌根菌共生在低磷狀態時,確實有較多側根。同時, SlCEP2 (C-terminally encoded peptides)基因表現於菌根菌接種後會持續下降,並與菌根菌共生提升的根部磷含量呈現負相關,顯示菌根菌造成的磷累積可能是SlCEP2表現下降的原因。處理幼苗合成的SlCEP2胜肽可造成側根密度及長度減少,IBA (生長素IAA的前驅物) 處理則可回復被SlCEP2影響的側根密度和長度。此外,受到SlCEP2胜肽影響的生長素在根尖和側根原基 (lateral root primordia) 的強度和極性分布,以及IBA轉換成IAA的酵素基因、生長素運輸載體和下游訊息傳遞的基因表現,都可因為 IBA 處理而恢復正常,顯示SlCEP2影響側根發育可能是藉由調控IBA轉換成IAA的途徑。SlCEPR1 (CEP receptor 1)基因靜默可提升番茄側根密度,同時,SlCEP2的胜肽處理不會影響SlCEPR1基因靜默植物的側根發育,顯示SlCEP2的受體可能為SlCEPR1。最重要的是,在SlCEP2過表現或是基因靜默的番茄中,側根生長無法進一步被菌根菌共生誘導,顯示SlCEP2確實為菌根菌促進植物根部發育機制中的重要基因。我們的研究揭示了,菌根菌共生或許可透過胜肽賀爾蒙以連結磷和生長素的訊號,並藉此調控側根發育。 | zh_TW |
dc.description.abstract | In response to arbuscular mycorrhizal (AM) fungi colonization, lateral root (LR) development is usually stimulated, accompanied with increased root phosphate content and auxin accumulation. Though both phosphate and auxin signaling has been postulated to be involved in AM-induced LR growth, the underlying molecular mechanism is still unclear. Here, we found tomato colonized with AM fungi indeed had increased LR. In addition, C-terminally encoded peptides (CEP) SlCEP2 was significantly downregulated in mycorrhizal roots, and this downregulation was negatively correlated with the accumulation of AM-derived phosphate, suggesting that repression of SlCEP2 might be due to the higher root phosphate derived from AM. Both LR density and length was significantly reduced under synthetic SlCEP2 peptide treatment; however, application of the IAA precursor, IBA, could rescue the defective LR density and length caused by SlCEP2 treatment. Furthermore, the impaired expression of genes involved in IBA to IAA conversion, auxin polar transport and LR-related signaling pathway in CEP2-treated roots could all be rescued by IBA application, strongly indicating that SlCEP2 might mediate LR growth through regulating IBA to IAA conversion. In SlCEPR1 (CEP receptor 1) knockdown plants, LR density was higher and even under SlCEP2 treatment, LR growth was unaffected, showing that SlCEPR1 may be the receptor of SlCEP2. Most importantly, LR density of SlCEP2 overexpression or knockdown plants cannot be further increased by AM inoculation, suggesting that SlCEP2 was critical for AM-induced LR growth. This new discovery may help us to clarify how AM regulates plants root development through modulating peptide hormone to connect phosphate and auxin signaling. | en |
dc.description.provenance | Made available in DSpace on 2021-06-08T03:34:52Z (GMT). No. of bitstreams: 1 U0001-2401202113555700.pdf: 5002698 bytes, checksum: 694b773ae2e3f655c0ddc27fcf1aba83 (MD5) Previous issue date: 2021 | en |
dc.description.tableofcontents | 摘要 ii Abstract iii List of Abbreviations v Table of Contents viii List of Figures x List of Supplemental Figures xi List of Supplemental Tables xii List of Appendixes xiii Chapter 1 Introduction 1 1.1 AM symbiosis promotes plant lateral root growth 1 1.2 Pre-symbiotic signaling is involved in AM-induced lateral root growth 3 1.3 Root phosphate content might be involved in AM-regulated lateral root growth 5 1.4 Auxin might contribute to AM-regulated lateral root growth 7 1.5 The role of auxin in mediating lateral root development 10 1.6 C-terminally encoded peptide (CEP) regulates both nodulation and lateral root growth in Medicago truncatula 15 Chapter 2 Materials and Methods 19 2.1 Plant materials, growth and AM inoculation conditions 19 2.2 Measurement of lateral root density and length 20 2.3 Generation of constructs 20 2.4 Tissue phosphate (Pi) quantification 22 2.5 Tomato hairy root generation and transformation 22 2.6 Root staining and quantification of AM colonization level 23 2.7 RNA extraction, cDNA synthesis and qRT-PCR 24 2.8 Synthetic peptide, IBA and NAA treatment 24 2.9 Imaging of auxin distribution 25 2.10 Virus mediated gene overexpression (VOX) and Virus induced gene silencing (VIGS) 26 2.11 Yeast two-hybrid system 26 2.12 Subcellular localization of CEP2 27 2.13 Accession numbers 28 Chapter 3 Results 29 3.1 AM symbiosis promoted tomato root growth and downregulated CEP2 gene expression in root 29 3.2 The expression pattern of root-abundant CEP2 responding to Pi content in root 30 3.3 CEP2 negatively regulates lateral root development 32 3.4 IBA or NAA application on the roots could recover CEP2Hyp-repressed lateral root growth to different extent 34 3.5 CEP2 affected auxin synthesis, transport and signaling 35 3.6 CEP2 peptide was possibly perceived by CEPR1 LRR-RLK 39 3.7 CEP2 expression during AM symbiosis was essential for AM-induced lateral root growth 42 Chapter 4 Discussion 46 4.1 The pre-symbiotic signal might not be involved in AM-induced lateral root growth in tomato 46 4.2 Phosphate starvation inhibits lateral root growth in tomato 47 4.3 Transcriptional regulation mechanism of CEP2 is still unclear 47 4.4 Subcellular localization of CEP2 needs further examination 49 4.5 CEP2-CEPR1 interaction plays a negative role in lateral root development 50 4.6 CEP2 inhibits lateral root growth via auxin-related pathways 53 4.7 IBA or NAA application results in different effects on CEP2-treated roots 55 4.8 AM-stimulated lateral root growth depends on fine-tuning of CEP2 expression 57 Figures 61 Supplemental Figures 67 Supplemental Tables 77 Appendixes 85 References 89 | |
dc.language.iso | en | |
dc.title | 探討SlCEP2胜肽荷爾蒙在叢枝菌根菌促進蕃茄側根生長中的角色 | zh_TW |
dc.title | Studying the role of SlCEP2 peptide hormone in arbuscular mycorrhizal fungi-mediated lateral root induction in tomato | en |
dc.type | Thesis | |
dc.date.schoolyear | 109-1 | |
dc.description.degree | 碩士 | |
dc.contributor.oralexamcommittee | 鄭秋萍(Chiu-Ping Cheng),張英峯(Ing-Feng Chang),林乃君(Nai-Chun Lin),邱子珍(Tzyy-Jen Chiou) | |
dc.subject.keyword | 叢枝菌根菌,磷,胜肽荷爾蒙,胜肽受體,生長素,側根發育, | zh_TW |
dc.subject.keyword | arbuscular mycorrizal (AM) fungi,phosphate starvation,C-terminally encoded peptide (CEP),leucine-rich repeat receptor-like protein kinase (LRR-RLK),auxin,lateral root growth, | en |
dc.relation.page | 104 | |
dc.identifier.doi | 10.6342/NTU202100138 | |
dc.rights.note | 未授權 | |
dc.date.accepted | 2021-01-28 | |
dc.contributor.author-college | 生命科學院 | zh_TW |
dc.contributor.author-dept | 植物科學研究所 | zh_TW |
顯示於系所單位: | 植物科學研究所 |
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