The Analysis of the Relationship Between Gene Expression and Production of Resveratrol in Wild Species of Genus Arachis

Resveratrol is a phytoalexin and is also an antioxidant, being considered a promising antitumour, cardioprotective and neuroprotective agent. Peanut is an allotetraploid specie with an AABB genomic constitution and A. ipaënsis and A. duranensis are the donors of the BB and AA genome, respectively. The objectives of this study were to evaluate the behavior of resveratrol synthase gene in A. hypogaea, in their diploid progenitors and in a synthetic allotetraploid. Resveratrol synthase (RS) is a key enzyme in the biosynthesis of resveratrol. Thus we studied the expression of RS by RT-qPCR and concentration of resveratrol by HPLC.

Leaf material were collected and the synthesis of resveratrol was induced by treatment with UV. All species synthesized resveratrol and the transcripts were significantly upregulated. Our results demonstrated that resveratrol accumulation was correspondent with RS gene expressions, suggesting the identification of one gene involved in the resveratrol synthesis induced by the UV treatment. Each genotype analyzed showed a different relationships among gene expression and biosynthesis of resveratrol. The cultivated peanut showed similar profile to synthetic allotetraploid. Arachis duranensis showed high concentration of the compound but low expression profiles of the RS. Arachis ipaënsisshowed high expression profiles of the RS and low concentration of the resveratrol.

The variation observed can be due to differences in time of response of each species to the stress. The improved knowledge of resveratrol production should facilitate the utilization of genetic resources for development of a variety with high nutritional value and disease resistance.