ThERF1 from Tamarix hispida confers decreased tolerance to oxidative and drought stresses and is regulated by a WRKY protein

The ethylene-responsive factor family is one of the largest families of plant-specific transcription factors that are involved in plant development and stress responses. Previously, we demonstrated that the gene Th ERF1,encoding a novel ethylene-responsive factor from Tamarix hispida, negatively modulates abiotic stress tolerance. In the present study, Arabidopsis plants overexpressing Th ERF1 had decreased oxidative tolerance and increased transpirational water loss rate compared with wild-type plants, leading to sensitivity to abiotic stress. Real-time RT-PCR showed that the upstream regulator of Th ERF1,Th WRKY2, is involved in responses to different abiotic stresses. Furthermore, both Th WRKY2 and Th ERF1 shared similar expression patterns in the stems and leaves of T.hispida when exposed to salinity, drought and abscisic acid. Chromatin immunoprecipitation assays further confirmed that Th WRKY2 can directly bind to the promoter of Th ERF1 and regulate its expression. This study revealed the regulatory mechanism of Th ERF1 expression in response to abiotic stresses in T. hispida.