Plants have evolved complex signaling networks that enable them to adapt to adverse environmental conditions. The dehydration-responsive element-binding (DREB) transcription factors are important for plant responses to abiotic stresses. In this study, a new member of the AP2/ERF transcription factor gene family, PcDREB2A, was cloned and characterized from Polygonum cuspidatum, a traditional Chinese medicinal herb. PcDREB2A, which includes a typical AP2 domain, was clustered in the A-2 subgroup of the DREB subfamily. At the seedling stage, PcDREB2A expression was induced by cold, salt, and drought stresses. A yeast one-hybrid assay and an analysis of transiently transformed tobacco revealed that PcDREB2A can specifically bind to the DRE motif and transactivate reporter gene expression. Following 200 and 250 mM mannitol treatments, the PcDREB2A-overexpressing Arabidopsis thaliana lines had longer roots and a significantly higher fresh weight than the wild-type plants. Furthermore, under drought stress conditions, the PcDREB2A-overexpressing A. thaliana plants accumulated less malondialdehyde than the control plants. These results indicate that PcDREB2A encodes a novel DREB transcription factor in P. cuspidatum. Furthermore, the data generated in this study may be useful for researchers and breeders interested in genetically engineering plants to increase drought tolerance without inhibiting growth.

植物已经进化出复杂的信号网络，使其能够适应不利的环境条件。脱水反应元件结合（DREB）转录因子对于植物对非生物胁迫的反应非常重要。在这项研究中，从传统中草药虎杖中克隆了AP2 / ERF转录因子基因家族的新成员PcDREB2A并对其进行了表征。包含典型AP2域的PcDREB2A聚集在DREB子家族的A-2子组中。在苗期，PcDREB2A寒冷，盐和干旱胁迫诱导了大豆蛋白的表达。酵母单杂交测定和瞬时转化烟草的分析表明，PcDREB2A可以特异性结合DRE基序并激活报告基因的表达。经过200和250 mM甘露醇处理后，过表达PcDREB2A的拟南芥品系比野生型植物具有更长的根部和明显更高的鲜重。此外，在干旱胁迫条件下，过表达PcDREB2A的拟南芥植物比对照植物积累更少的丙二醛。这些结果表明PcDREB2A编码在虎杖中的一种新的DREB转录因子。。此外，本研究中产生的数据可能对对基因工程植物感兴趣的研究人员和育种者有用，它们可以在不抑制植物生长的情况下提高其耐旱性。