The AabHLH35 Transcription Factor Identified from Anthurium andraeanum is Involved in Cold and Drought Tolerance

Anthurium andraeanum Lind. is a popular potted and cut-flower plant with an attractive spathe and foliage. It is native to tropical rainforest areas and is able to blossom throughout the year under suitable conditions. However, various abiotic stresses seriously restrict the ornamental value of A. andraeanum and increase the costs of cultivation. A dark green (dg) leaf color mutant of A. andraeanum 'Sonate', which accumulates high levels of anthocyanin, has shown increased vigor and tolerance to stresses during cultivation and is, thus, an ideal germplasm for studying stress tolerance in this species. Here, we show that the anthocyanin content in dg mutant plants at different stages of leaf development was higher than in wild-type (WT) plants, and the ability to tolerate under low-temperature (LT, 14 °C) stress was stronger in dg than in WT plants. RNA-Seq of cDNA libraries from young leaves of dg and WT identified AabHLH35 as a differentially expressed gene (DEG) that was significantly up-regulated in dg. Furthermore, heterologous expression of AabHLH35 improved tolerance to cold and drought stresses in Arabidopsis. These results have built an important molecular foundation for further study of stress tolerance in A. andraeanum.