基因與微核醣核酸於楓香秋季葉變色表現之探討

Abstract

本研究以臺灣原生樹種楓香（Liquidambar formosana Hance）為材料，使用微矩陣（microarray）偵測楓香綠葉、紅葉及黃葉微核醣核酸的表現。由分析結果得知miR164、miR828、miR157及miR172等微核醣核酸（microRNA）家族有明顯之差異表現，經由可能的調控途徑推衍，判知miR164、miR828、miR157及miR172可能參與楓香葉老化、葉變色及葉片生長發育之調控。此外，配合葉變色相關基因pheophorbide a oxygenase（PaO）、dihydroflavanoid reductase（DFR）及anthocyanidin synthase（ANS）於不同時期之表現情形、啓動子序列分析資料及葉片色素含量之測定，確認微核醣核酸於落葉性木本植物葉老化及葉變色調控之作用。本研究為首篇提出微核醣核酸參與調控秋季葉老化及葉變色之研究報告。

The leaves of different developmental stage of Formosan sweetgum (Liquidambar formosana Hance), a native species of Taiwan, were analyzed by using microarray to detect the expression of microRNA genes, including green, red and yellow leaves. The identified microRNA genes miR164, miR828, miR157 and miR172 were involved in Formosan sweetgum leaf senescence, coloration and development. Couple with chlorophyll quantification, anthocyanin absorbance measurement, promoter analysis and genes expression of coloration associated genes pheophorbide a oxygenase (PaO), dihydroflavanoid reductase (DFR) and anthocyanidin synthase (ANS), confirm that the current model of microRNA genes for leaf senescence and coloration did occur in Formosan sweetgum. This is the first study illustrate microRNAs as regulators in autumn leaf senescence and coloration.