MlNAC2基因的克隆及其在南荻根部的表达模式

Cloning MlNAC2 gene from Miscanthus lutarioriparius(Poaceae) and its expression profile in roots

克隆南荻MINAC2基因的c DNA序列,该序列全长为933 bp,编码产物含310个氨基酸残基,其蛋白质理论相对分子质量为34 427.8,等电点(p I)为5.85,不稳定系数为34.84,为稳定蛋白,具有保守的NAM基序,无信号肽和跨膜结构域,可推测其为亲水性蛋白。亚细胞定位试验结果表明,Ml NAC2定位于细胞核,可能在细胞核内行使功能。转录激活试验结果表明,Ml NAC2是一个转录因子蛋白,且转录激活域位于C端。荧光实时定量PCR分析结果表明,高盐、干旱、脱落酸、茉莉酸甲酯和机械伤害均能诱导Ml NAC2基因在南荻根部的表达上调,而低温处理时表达下调。

A full length of 933 bp c DNA sequence encoded with 310 amino acid residues of Ml NAC2 was cloned from Miscanthus lutarioriparius. The theoretical molecular weight and isoelectric point of this protein were 34 427.8 and 5.85, respectively, and it could be classified to stable proteins with an instability index about 34.84. Ml NAC2 was assumed as a hydrophilic protein for its protein sequence contained a conservative NAM motif and no signal peptide or transmembrane structure. The subcellular localization assay confirmed that Ml NAC2 was located in the nucleus and therefore might function in this subcellular. Transactivation assay indicated that Ml NAC2 was a transcription factor protein and the transactivation region located at its C–terminus. Result from real-time quantitative PCR test suggested that the transcript of Ml NAC2 at the roots of Miscanthus lutarioriparius was up-regulated at high salt, drought, ABA, Me JA or mechanical injuries, on the contrary, it was down-regulated at cold, but did not give response to SA.