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NAC 转录因子是植物中数量最大的转录因子,在植物的生长发育及各种逆境胁迫中发挥非常重要的作用.本研究以太行菊的叶片为研究材料,运用RT-PCR 及RACE 技术克隆得到一条太行菊的NAC 基因完整的cDNA 序列,命名为OpNAC1 (GenBank 登录号MF996370),并对其进行了生物信息学分析.分析表明,OpNAC1 基因cDNA 序列全长1 208 bp,ORF 全长855 bp,编码284 个氨基酸.预测其蛋白分子量32.68 kD,等电点6.46,属于不稳定亲水性蛋白.不含有信号肽和跨膜结构,很可能定位于细胞核.OpNAC1 与菊花 (ADQ20114.1)亲缘关系较近,同源性达93.7％.二级结构预测表明,OpNAC1 蛋白由40 个α- 螺旋(14.08％)、47 个β- 折叠(16.55％)和197 个无规则卷曲(69.37％)组成,与三级结构预测基本相符.研究结果为今后深入研究NAC 转录因子在太行菊中的生物功能提供基础.“,”NAC transcription factor is a transcription factor with the largest number in plant,and plays a very important role in plant growth and development and all kinds of stress response.In this study,the leaves of Opisthopappus taihangensis were used as materials.The complete cDNAsequence of NAC gene that named OpNAC1 (GenBank accession No.MF996370) was obtained successfully through the cloning by RT-PCR and RACE method,which was then applied to bioinformatics analysis.The results indicated that the full-length of cDNA sequence of OpNAC1 gene was 1 208 bp,and the ORF was 855 bp with 284 amino acids encoded.Thus,OpNAC1 gene was predicted to be an unstable hydrophilic protein with 32.68 kD protein molecular weight and 6.46 isoelectric point,which had no signal peptide and transmembrane region,and was likely to locate in the nucleus.OpNAC1 gene was close to Chrysanthemum (ADQ20114.1) in genetic relationship with the homology of 93.7％.The secondary structure analysis indicated that OpNAC1 protein was composed of 40 α-helixs (14.8％),47 β-sheets (16.55％) and 197 random coils (69.37％),which conformed to the prediction of the tertiary structure.The results might provide a basis for further research on the biological functions of NAC transcription factors in Opisthopappus taihangensis.