篇名 | 香蕉重泛素基因之選殖與分析 |
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卷期 | 54:2 |
並列篇名 | Cloning and Characterization of Polyubiquitin Genes in Banana |
作者 | 汪雅瑩 、 杜宜殷 |
頁次 | 127-138 |
關鍵字 | 基因表現 、 重複單位 、 啟動子 、 基因組庫 、 gene expression 、 genomic library 、 repeat unit 、 promoter |
出刊日期 | 200806 |
本研究選取香蕉基因組選殖系λBUq137 進行定序分析。此選殖系包含重泛素基因Mh-UBQ4,演繹之蛋白質具有533 個胺基酸,推測分子量為59.7 kDa。Mh-UBQ4 具有7 個泛素重複單位,頭接尾 (head-to-tail) 的方式相接,各重複單位中之胺基酸序列有些微差異。以Mh-UBQ4 專一性片段為探針進行香蕉各部位北方雜交分析結果,顯示此基因於果肉的表達量高於果皮及其他部位,產生之雜交訊號約1.7 kb。以不同後熟程度分級之香蕉果實,於4℃、15℃、及25℃處理24 小時後,進行北方雜交分析結果,4℃處理以第三級果肉表達量最高、25℃處理以第五級果肉
表達量較高,而15℃處理則各級果肉表達量相當。
A banana (Musa AAA group Cavendish subgroup) genomic clone λBUQ137 containing polyubiquitin gene Mh-UBQ4 was isolated and analyzed. Mh-UBQ4 encodes a highly conserved 533-amino acid protein with predicted molecular weight of 59.7 kDa. The deduced polypeptide contains seven head-to-tail repeats of ubiquitin and slight difference in amino acid sequence exists among repeats. Using the gene specific fragment as probe, Northern blot analysis indicated that expression level of Mh-UBQ4 transcript, sizing 1.7 kb, was higher in pulp than in other organs. The accumulation of Mh-UBQ4 mRNA in fruit pulp was slightly enhanced by 4oC and 25oC incubation for 24 hours for fruits at ripening stage 3 and 5, respectively. When incubated at 15℃ for 24 hours, banana pulps in all ripening stages had similar expression of the gene.