NAC转录因子是特异存在于植物中具有多种生物功能的新型转录因子。本实验从花生中克隆了2个NAC基因AhNAC2和AhNAC3(GenBattk登录号为EU755023和EU755022);蛋白序列分析表明,两者具有典型NAC转录因子特征,N端含有保守NAC结构域。半定量RT-PCR显示,在ABA和GA3处理,以及控水和低温条件下,AhNAC2和AhNAC3在花生组织中的表达上调,呈现不同的表达模式。AhNAC2和AhNAC3为典型的NAC转录因子新基因,蛋白序列与拟南芥RD26同源性较高,推测与响应干旱和ABA信号有关。
NAC transcription factors existed differentially in plant are the new transcription regulatory factors with multiple biological functions. Two NAC-like genes from peanut were cloned by RT-PCR and RACE methods, named AhNAC2 and AhNAC3 (GenBank accession No. EU755023 and EU755022), which contain an ORF of 1 050 bp and 1 008 bp and encode 349 and 335 amino acids, respectively. Gene sequence analysis showed that the putative protein of both two genes contained conserved NAC domain and highly different C terminal which is the typical characteristics of NAC transcription factors. Meanwhile, the transcription levels of the two genes were investigated by semi-quantitative RT-PCR, and the result showed that the expressions of AhNAC2 and AhNAC3 genes were enhanced by ABA, GA3, water stress, and cold stress respectively. Furthermore, the two genes expressed constitutively in peanut tissues, and their expression patterns were different in various tissues. In conclusion, AhNAC2 and AhNAC3 genes isolated from peanut were new members of NAC transcription factor family, their comparison to RD26 (AT4G27410) reveals a high amino acid homology. We suggested that they play key roles in ABA signal transduction and drought response in peanut.