Identification of drought-induced transcription factors in peanut (Arachis hypogaea L.)

Transcription factors play key roles in the regulation of genes involved in normal development as well as tolerance to biotic and abiotic stresses. Specific transcription factors that are induced in peanut under drought conditions have not been identified. The objectives of this study were to compare gene-expression patterns of various transcription factors of a drought tolerant versus a susceptible peanut genotype under drought conditions and to identify transcripts that were regulated in a drought dependent manner. Twelve putative transcription factors were identified and real-time PCR analysis was performed which resulted in the identification of three unique transcripts in which ahERF1 was highly induced in the recovery stage; ahERF7 and ahERF8 were also highly induced by drought and returned to nominal levels after recovery. These sequences contain DNA binding domains that are present in the APETALA2/Ethelene Responsive Factors (AP2/ERF) family of transcription factors which have been shown to be induced by stress. Induction levels and patterns of gene-expression of ahERF1, ahERF7 and ahERF8 may be used to select plants that may have higher drought tolerance