Abstract: NAC proteins are  plant-specific transcription factors, which play important roles in plant development and response to various abiotic stresses. In order to better reveal the stress tolerance function of the maize SNAC (stress-responsive NAM, ATAF1/2, CUC2) family,  the structural characteristics and possible regulatory mechanisms of the genes was predicted. This paper identified 16 SNAC family genes in maize by bioinformatics, and analyzed the physical and chemical properties, gene structure, potential phosphorylation sites, protein secondary structure, gene evolution relationship, amino acid sequence characteristics and promoter binding elements of each protein family. The results showed that 16 SNAC  genes in maize had no transmembrane structure, and all had N-terminal conservative domain and highly variable C-terminal domain. Most closely related members in the same subgroup had similar gene structure. There were a large number of phosphorylation sites in SNAC genes by the analysis of phosphorylation, and many cis-acting elements in the promoter region of SNAC genes. The prediction of secondary structure showed that the transcriptional regulatory region of SNAC in maize had high internal flexibility. Promoter analysis showed that there were a large number of cis-acting elements in the promoter region of SNAC gene family. These results provided candidate genes for the study of maize stress tolerance,  and were of great significance to the advancement of the functional analysis of maize SNAC family.

Key words: maize (Zea Mays L.), SNAC gene family, gene structural characteristics, biotic and abiotic stresses

摘要： NAC蛋白是植物特有的转录因子，在植物发育和各种非生物逆境应答中发挥着重要作用。为更好地揭示玉米SNAC(stress-responsive NAM,ATAF1/2,CUC2)家族的耐逆境胁迫功能，对其基因的结构特征及可能的调控机理进行了预测。利用生物信息学方法，鉴定了玉米16个SNAC家族基因，并对该基因家族各编码蛋白的理化性质、基因结构、潜在的磷酸化位点、蛋白质二级结构、基因进化关系、基因组序列结构和启动子结合元件等信息进行分析。分析结果表明：玉米16个SNACs不具有跨膜结构，且均具有N-末端保守结构域和高度可变的C-末端结构域。系统发育分析表明，同一亚群中密切相关的成员具有相似的基因结构，推测在不同植物中会具有类似的耐逆功能。磷酸化位点分析表明，玉米SNAC家族存在着大量的磷酸化位点。二级结构预测表明，玉米SNAC的转录调控区具有高度的内在灵活性。启动子分析表明，玉米SNAC家族基因启动子区域均含有大量的逆境胁迫应答顺式作用元件。这些结果为玉米耐逆境研究提供了候选基因，对促进玉米SNAC家族功能分析的进展具有重要意义。

关键词: 玉米（Zea Mays L.）, SNAC基因家族, 基因结构特征, 逆境胁迫