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

Abstract

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 ThERF1, encoding a novel ethylene-responsive factor from Tamarix hispida, negatively modulates abiotic stress tolerance. In the present study, Arabidopsis plants overexpressing ThERF1 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 ThERF1, ThWRKY2, is involved in responses to different abiotic stresses. Furthermore, both ThWRKY2 and ThERF1 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 ThWRKY2 can directly bind to the promoter of ThERF1 and regulate its expression. This study revealed the regulatory mechanism of ThERF1 expression in response to abiotic stresses in T. hispida.

Keywords

Abiotic stress / Ethylene response factor / Tamarix hispida / ChIP / Real-time RT-PCR

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