阿拉伯芥開花基因AGL24與FVE參與系統性開花調控之研究

Study on systemic floral regulation by flowering genes AGL24 and FVE in Arabidopsis

劉瑜珊(Yu-Shan Liu)

指導教授 ： 王淑美

共同指導教授 ： 余天心(Tien-Shin Yu)

國立臺灣大學/生命科學院/植物科學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.10126

摘要

開花，是由植物體內局部性或系統性的開花訊息因子所共同調控。其中最廣為人知的開花素「FLOWERING LOCUS T (FT)」，會受到光週期的刺激而活化，並由葉片經韌皮部長距離的運送至莖頂而誘導開花。近來的微陣列結果與嫁接實驗發現，「AGAMOUS-LIKE 24 (AGL24)」與「FVE」兩個阿拉伯芥開花基因的RNA亦可由轉殖株砧木長距離移動至接穗中。因此，本篇研究主要目的為探討內源的AGL24 與 FVE RNA 在植物中長距離移動之能力，並針對其誘導開花的功能性作進一步的研究。為了解 AGL24 及 FVE 的非細胞自主 (non-cell autonomous) 功能性，我利用具組織專一性的啟動子在突變株中改變 AGL24 及 FVE 表現量。藉此互補實驗發現韌皮部中 AGL24 與 FVE 的表現量改變時，會影響到植物莖頂的開花時間。此外，利用阿拉伯芥嫁接方式及反轉錄聚合酶連鎖反應(RT-PCR) 的分析，證實內源的 AGL24 RNA 具有於韌皮部中長距離運送的能力。而利用阿拉伯芥轉殖技術及共軛焦顯微鏡觀察結果得知，FVE 的蛋白質可能具有從韌皮部的伴細胞運送至表皮細胞的能力。因此，我推測 AGL24 與 FVE 可能在植物的開花途徑中，扮演著系統性開花調節因子的角色。

關鍵字

AGL24 ； FVE ； 長距離運輸 ； 嫁接 ； 阿拉伯芥

並列摘要

Floral initiation is regulated by many local and systemic florigenic signals. In addition to FLOWERING LOCUS T (FT), which mediates systemic photoperiodic signal, evidences show that other systemic floral regulators may participate in floral induction. Previous microarray analysis reveals that the RNA of some floral regulators is presented in broccoli phloem sap. Further Arabidopsis grafting experiments demonstrate that at least two phloem sap RNA, AGAMOUS-LIKE 24 (AGL24) and FVE, moves long-distance in transformants. In this study, we aim to investigate the systemic florigenic avtivity of endogenous AGL24 and FVE RNA. To determine the non-cell autonomous function of AGL24 and FVE, we ectopically expressed the AGL24 and FVE in comanion cells and found that the expression of AGL24 and FVE in companion cells is sufficient to promote floral initiation. We also examined the RNA movement of endogenous AGL24 and FVE and found that endogenous AGL24 RNA is a non-cell autonomous RNA. In addition, our preliminary results demonstrated that the FVE protein may be a non-cell autonomous protein. In conclusion, our data showed that AGL24 and FVE may participate in systemic floral regulation.

並列關鍵字

AGL24 ； FVE ； RNA movemen ； grafting ； Arabidopsis

參考文獻

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