AT-hook (AHL)蛋白家族在植物生长发育、器官构建、逆境胁迫及植物激素信号应答中发挥关键作用。为揭示菠菜AHL基因家族生物功能, 本研究在菠菜基因组范围内对菠菜SoAHL家族成员进行鉴定和分析, 并研究外源水杨酸对其表达水平的影响。结果表明, 菠菜SoAHL家族包含19个成员, 在6条染色体间不均匀分布, 系统发育树将其分为2个亚族, I、II亚族分别包含10、9个SoAHL成员; 不同亚族间PPC和AT-hook保守基序序列组成有差异; SoAHL主要定位在细胞核、细胞质、线粒体; SoAHL I亚族成员无内含子, II亚族成员含4-5个内含子;  SoAHL启动子上游分布有不同数量的植物激素和非生物胁迫响应相关顺式作用元件。SoAHL成员在根、叶、柄中均有表达, 大多数在根中表达水平较高; 水杨酸处理条件下, SOV6g041850.1和SOV2g038950.1显著受水杨酸诱导; SOV2g031340.1和SOV4g018880.1主要在地上部分表达, 与叶酸含量的组织分布特征相似。瞬时过表达SOV4g018880.1能提高菠菜叶酸含量1.27倍。本文研究结果可为进一步解析菠菜SoAHL的功能奠定基础。

The AT-hook motif nuclear localized (AHL) gene family is a highly conserved transcription factors involved in plant growth, development, and stress responses. To reveal the basic characteristics of AHL family in spinach, the members of the spinach SoAHL family were identified at the whole genome level, and their physicochemical properties, gene structure, conserved motifs, promoter elements, and salicylic acid-responsive expression profiles were analyzed in this study. Resulted showed that there were 19 SoAHL family members in spinach genome, which were unevenly distributed across six chromosomes. These SoAHL members can be classified into three branches, with 10 members in subfamily I and 9 members in subfamily II. Sequence composition of PPC and AT-hook conserved motifs varies among subfamilies; most of the SoAHL genes were located in nucleus, cytoplasm, and mitochondrion. Members of subfamilies I of SoAHL have no introns, while members of subfamily II contain 4–5 introns. The varying numbers of cis-acting elements about hormones and abiotic stress responses were distributed upstream of the promoters of SoAHL members. The SoAHL genes can be expressed in roots, leaves, and petioles, with most genes expressed at higher levels in roots. The expression of two SoAHL genes (SOV6g041850.1 and SOV2g038950.1) were significantly induced by salicylic acid treatment. The expression profiles and salicylic acid-induced expression levels of SOV2g031340.1 and SOV4g018880.1 were highly correlated with folic acid content, which may play a role in spinach response to salicylic acid signalling pathway. The transient overexpression of SOV4g018880.1 increased the folate contents of spinach leaves by 1.27 times. Our results will lay the foundation for further resolving the function of spinach AT-hook genes.