2022年7月7日 星期四
石蒜 Mg2+ 转运体基因 LrMGT 的克隆与分析
Cloning and analysis on Mg2+ transporter gene LrMGT from Lycoris radiate
2014年 第23卷 第4期 页码[1-7]    下载全文[5.6MB]  
摘要

从石蒜[Lycoris radiata (L’Hér.) Herb.]叶片全长 cDNA 文库中克隆获得 Mg2+转运体(MGT)基因 LrMGT。 序列分析结果显示:LrMGT 基因的 cDNA 序列全长 1 726 bp,其中开放阅读框(ORF)长度 921 bp,编码 306 个氨基酸。石蒜 LrMGT 基因编码的氨基酸序列的理论相对分子质量为 33 635,理论等电点为 pI 5. 14,为疏水性膜蛋白,不具有信号肽。 序列比对结果表明:石蒜 LrMGT 基因编码的氨基酸序列与小米[ Setaria italica ( Linn.) Beauv.]、水稻(Oryza sativa Linn.)和拟南芥[Arabidopsis thaliana (Linn.) Heynh.]等植物的 MGT 基因编码的氨基酸序列的相似性较高,相似度达到 72% ~ 76% ;石蒜 LrMGT 基因与其他植物 MGT 基因编码的氨基酸序列的保守区域较大,均具有较高的保守性。 在 NJ 系统树上石蒜 LrMGT 基因编码的氨基酸序列与禾本科( Gramineae) 植物二穗短柄草[Brachypodium distachyum (Linn.) Beauv.]、水稻、高粱[Sorghum bicolor (Linn.) Moench]和小米 MGT 基因编码的氨基酸序列聚为同一个分支,表明它们可能具有较近的进化关系。 实时荧光定量 PCR 结果表明:石蒜 LrMGT 基因在根和鳞茎中的相对表达量较高,在叶片和花中的相对表达量较低,具有明显的组织特异性。

Abstract

Mg2+ transporter (MGT) gene LrMGT was cloned from the full-length cDNA library in leaf of Lycoris radiata (L’Hér.) Herb. Result of sequence analysis shows that the full-length of cDNA sequence of LrMGT gene is 1 726 bp with an open reading frame. ( ORF) of 921 bp, which encodes 306 amino acids. The theoretical relative molecular weight of the amino acid sequence encoded by LrMGT gene from L. radiata is 33 635 and its theoretical isoelectric point is pI 5. 14, and which is hydrophobic membrane protein without signal peptide. The result of sequence alignment shows that amino acid sequence encoded by LrMGT gene from L. radiata possesses higher similarity to those encoded by MGT gene from Setaria italica (Linn.) Beauv., Oryza sativa Linn. and Arabidopsis thaliana (Linn.) Heynh., etc, with similarity degree of 72% -76% . There is large conserved region in all of the amino acid sequences encoded by LrMGT gene from L. radiata and MGT gene from other species, which possess high conservation. In NJ phylogenetic tree, the amino acid sequences encoded by LrMGT gene from L. radiata and by MGT gene from other species in Gramineae such as Brachypodium distachyum (Linn.) Beauv., O. sativa, Sorghum bicolor (Linn.) Moench and S. italica are clustered together, meaning that these species have the closer evolution relationship. The real-time fluorescence quantitative PCR result shows that the relative expression of LrMGT gene from L. radiata is higher in root and bulb and lower in leaf and flower with an obvious tissue specificity.

 

关键词石蒜; Mg2+转运体; 基因克隆; 序列分析; 同源性; 表达特性
Key wordsLycoris radiata ( L’Hér.) Herb.; Mg2+ transporter; gene cloning; sequence analysis; homology; expression characteristics
作者汪仁, 蔡黎丽, 徐晟, 李晓丹, 夏冰
所在单位江苏省• 中国科学院植物研究所(南京中山植物园), 江苏 南京 210014
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下载次数362
基金项目国家自然科学基金资助项目(31301798); 江苏省盐土生物资源研究重点实验室开放课题(JKLBS2012010)